Update on Infections

Update on Infections
By:Mark A. Lassoff, MD, MBA, MPH
September 18, 2007

Malacoplakia
* “malako” – soft, “plakos” – plaque
* Rare granulomatous disease
* Michaelis – Gutmann bodies: basophilic lamellar inclusion bodies
* Associated with other autoimmune diseases
o Sarcoidosis, Chedak-Higashi syndrome
* Incidence: 1 in 10,000
* Female: Male – 4:1
* Peak incidence is in patients ≥ 50 yrs old
* 75% of cases occur in GU system, most commonly in the bladder (2nd – kidney)
* Predilection for those with immunodeficiency, systemic dz, carcinoma or chronic UTI with coliform organisms (E Coli – up to 75%, Enterobacter, Klebsiella, Proteus and Pseudomonas)
* Etiology – unknown
o Theory: acquired immunodeficiency interfering with normal intracellular function of the monocyte’s phagolysosome. Residual undigested bacterial components become mineralized by Ca++ & Fe
o Cause appears to be related to imbalance in the intracellular cGMP/cAMP
* Dx made by biopsy
o Lesion: large histiocytes  von Hansemann cells and small intracytoplasmic calculospherules  Michaelis-Gutmann bodies
o Immunohistochemical staining for α1-antitrypsin useful for early and accurate differential dx
* Clinical findings
o Bladder
+ Irritability and hematuria
+ Mucosal plaques or nodules  fungating, firm, sessile masses
o Renal
+ Bilaterality in up to 50%; multifocal is more common
+ Fever, flank pain or mass on PE
+ Cause loss of function via direct invasion or obstruction
+ E Coli infxn in up to 93%
+ Bilateral dz  mortality rate approaches 100% w/i 6 mos of dx w/o intervention
+ IVP: unifocal – may displace calyces vs. multifocal – nephromegaly and poor renal fxn; multiple filling defects
* Management
o Lower tract:
+ Initial treatment with medications
# Bethanecol (↑ cGMP), Ascorbic acid (↓ cAMP)
# Fluoroquinolones (DOC)
# Others: Bactrim, Rifampin, Cipro
+ TUR prn for plaque removal
o Upper tract:
+ Unilateral renal dz: most often requires nephrectomy
o In immunodeficient pts and those with multifocal dz, surgical tx is essential to survival

Sexually Transmitted Infections
Syphilis
* Treponema pallidum (spirochete)
* Spread: infectious lesions, body fluids, in utero, blood transfusions
* Primary
o Single painless, indurated ulcer appearing 3 wks after inoculation (@ site of inoculation) and remains for 4 – 6 wks
o Often with bilateral, non-tender inguinal or regional lymphadenopathy
o Can heal w/o treatment; often goes unnoticed
o Presence of chancres increases risk of HIV acquisition 2-5x
* Latent
o Seroreactivity w/o clinical evidence of dz
o Early: within the last year
o Late latent vs. latent syphilis of unknown duration
* Secondary
o Begins 4 – 10 wks after the appearance of the ulcer but may present up to 24 mos after initial infection
o Mucocutaneous, constitutional and parenchymal signs and symptoms
+ Maculopapular rash (trunk and arms)
+ Generalized non-tender lymphadenopathy
+ Papular rash (may accompany first rash)
# Becomes necrotic and pustular
# Affects palms and soles
# Intertriginous areas: enlarge and erode  condyloma lata (infectious)
+ Less commonly: hepatitis and immune-complexed glomerulonephritis
* Tertiary
o One third of untreated pts
o Rare in industrialized countries, except for pts w/ HIV
o Cardiovascular, skeletal, CNS, skin
+ Aortitis, meningitis, uveitis, optic neuritis, general paresis, tabe dorsalis, gummas of skin/skeleton
* Screening
o Rapid Plasma Reagin (RPR) & Venereal Disease Research Laboratory (VDRL)
+ Correlate with disease activity
+ Become negative one year after treatment
o T. pallidum particle agglutination (TP-PA) or Fluorescent Treponemal Antibody Absorbed (FTA-ABS)
+ Antibody tests remain positive for life; do not correlate w/ active disease
o HIV can cause FN results by treponemal & non-treponemal methods
* Treatment
o Benzthiazide penicillin G (2.4 million units IM x 1)
o Jarisch – Herxheimer rxn
+ Headaches, myalgia, fever, tachycardia, increased resp rate within first 24 hrs after tx w/ PCN
+ Managed with bed rest and NSAIDs
o PCN allergy: Doxycycline (100mg BID x 14d)
o Latent: PCN IM weekly x 3 doses or doxycycline for a total of 4 wks
o Tertiary: Aqueous crystalline PCN G (IV q4h) x 10-14 d or PCN G procaine IM + probenecid (po QID) x 10-14 d
o Pregnancy: desensitization to PCN

Herpes Simplex Virus
* Genital herpes: HSV-2 (85-90%), HSV-1 (10-15%)
* Silent infection may account for >75% of transmission
* Primary
o Painful ulcers of genitalia or anus
+ Group of vesicles on an erythematous base that does not follow a neural distribution is pathognomonic
o Bilateral painful inguinal adenopathy
o Often associated with constitutional flu-like symptoms
o Urethral lesions may cause transient urinary retention in women
o Asx viral shedding can happen up to 3 mos after clinical presentation
* Recurrent episodes are usually less severe
* Severe dz and complications:
o Pneumonitis, disseminated infxn, hepatitis, meningitis, encephalitis
* Dx: viral culture with subtyping (gold standard)
o Not on clinical suspicion alone, classic presentation occurs in a small percentage of pts
o Can see abrasions, fissures or itching
o Subtyping is important for prognosis and counseling
+ HSV-2: ave of 4 recurrences in 1st yr vs. 1 for HSV-1
o Sensitivity: 30 – 95% depending on stage of lesion and whether it is primary or recurrence
* Treatment
o Oral acyclovir, valacyclovir and famciclovir
o Topical meds are not effective
o Recurrences: episodic or suppressive approach
+ Suppressive: decreases frequency/duration and viral shedding
Chancroid
* Haemophilus ducreyi
* Men: Women – 3:1
* Painful, non-indurated ulcer on penis or vulvovaginal area
o Friable base covered with a gray or yellow purulent exudate and a shaggy border
* Inguinal adenopathy is typically unilateral and tender with tendency to become suppurative and fistulize
* Dx: culture media not widely available so gram stain often helpful (short, fine, GN streptobacilli in short, parallel chains)
* Approximately 10% are co-infected w/ HSV or syphilis
* Treatment
o Single dose
+ Azithromycin 1gm po or Ceftriaxone 250mg IM
o Other tx: Cipro x 3d or Erythromycin x 7d

Lymphogranuloma Venereum
* Chlamydia trachomatis – L1, L2, L3
* Single, painless ulcer on the penis, anus or vulvovaginal area that goes unnoticed
* Painful unilateral suppurative inguinal adenopathy and constitutional symptoms that occur 2 – 6 wks after resolution of ulcer
* Significant tissue injury and scarring can occur leading to labial fenestration, urethral destruction, anorectal fistulas and elephantiasis of penis, scrotum or labia
* Dx: mainly clinical
o Complement fixation or indirect fluorescence antibody titers can confirm
* Tx: Doxycycline BID or erythromycin QID x 3 wks

Genital Warts
* Condylomata acuminata
* Human papillomavirus (HPV) – DNA virus
* Types 6 and 11 are most often responsible for visible external genital warts
o Cervix, vagina, urethra, anus, mucous membranes
* Types 16, 18, 31, 33, 35, 39, 45 and 51: associated with cervical dysplasia and neoplasm in women and squamous intraepithelial neoplasia in men
o >99% of cervical cancers and 84% of anal cancers are associated with HPV (16 & 18)
o Cervical cancer is considered an AIDS defining illness
* Most are subclinical and asx
* In women HPV may be associated with nonspecific symptoms such as vulvodynia or pruritis; malodorous vaginal discharge
* Dx: usually inspection or palpation
* Bx: not routinely needed
o Atypical, pigmented, indurated, fixed or ulcerated
o Lesions persist/worsen after tx; immunocompromised pts
* Treatment
o Depends on size, number, location, and patient and physician preference
o Observation (spontaneously resolve with time)
o Patient applied (less expensive)
+ Podofilox 0.5% solution or gel (3d on, 4d off, may repeat x 4)
+ Imiquod 5% cream (3/wk qhs for up to 16 wks)
# Needs to be washed off, can cause ulceration
o Provider applied
+ Cryotherapy with liquid nitrogen
+ Electrosurgery
+ Laser therapy (CO2)
+ Podophyllin resin (20 – 25%)
+ Trichloracetic acid (TCA) or bichloracetic acid (BCA)
+ Surgical excision
* Lesions around the meatus may herald presence of urethral or bladder condyloma
* Urethral or bladder lesions should be cystoscopically excised
* Intraurethral 5% FU cream 2/wk
* Vaccine containing 8 of the most common HPV types associated with cancer could potentially prevent 95% of cervical cancer
* Topical BCG: promising preliminary results

Sexually Transmitted Infections
Chlamydia
* Chlamydia trachomatis: most common bacterial STD in the US and worldwide
* Majority of men and women are asx
* 50% of men experience LUTS attributed to urethritis, epididymitis or prostatitis; may see clear or white urethral discharge
* 75% of women are asx and 40% of those untreated will have PID
* May be transmitted during vaginal birth
o Ocular, oropharyngeal, respiratory, urogenital or rectal infxn
Chlamydia
* Women should be screened annually until 25 yo or if risk factors such as new sexual partner are present
o Nucleic acid amplification test (NAAT) on endocervical swab or urine specimen
o Unamplified nucleic acid hybridization test, enzyme immunoassay or direct fluorescence antibody test
o Culture
* Treatment
o Azithromycin 1gm po x 1 or Doxy BID x 7d
o Refrain from sex until treatment completed or 7d after single dose therapy
o Re-culture recommended 3 wks later if treated with erythromycin, in pregnant women or if symptoms persist
o Re-screened 3 – 4 mos after tx as are high risk for re-infxn

Gonorrhea
* Neisseria gonorrhoeae (GN diplococcus)
* Men usually experience LUTS attributed to urethritis, epididymitis, proctitis or prostatitis w/ associated mucopurulent urethral discharge
* Women may have vaginal and pelvic discomfort, dysuria or abnormal vaginal discharge but are usually asx
* Same screening recs as for Chlamydia
* Treatment
o Ceftriaxone 125mg IM x 1
o Single dose oral regimen
+ Cipro, Levaquin, Ofloxacin (growing resistance to FQs)
o Simultaneous treatment for Chlamydia






Trichomoniasis

* Trichomonas vaginalis (flagellated protozoan)
* Increased incidence in developing countries and those with multiple sexual partners
* Can inhabit the vagina, urethra, Bartholin glands, Skene’s glands and prostate (not rectum/mouth)
* Men: usually asx but can produce short-term urethral discharge, dysuria and urgency
* Women: asx in 50%, otherwise can see sudden onset of frothy white or green, foul-smelling vaginal discharge, pruritis, and erythema
o Dyspareunia, suprapubic discomfort, urgency
Trichomoniasis
* Examination: frothy discharge and “strawberry vulva” or “strawberry cervix”
* Vaginal discharge has increased pH
* Motile protozoa on vaginal wet-mount smear or microscopic examination of urine
* Men: urethral cx or microscopic exam of urine
* Treatment
o Metronidazole 2gm po x 1 (ok in 2nd trimester)
+ GI side effects common
o Abstain from Etoh consumption
o Prolonged Metronidazole for failure

Vaginitides / Urethritides
* Ureaplasma urealyticum, Mycoplasma hominis, Mycoplasma genitalium
o Implicated in chronic prostatitis and urgency frequency symptoms in women and in up to 40% of NGU
o Tx: Azithromycin po x 1 or doxycycline x 2 wks
* Bacterial vaginosis
o Gardnerella vaginalis, anaerobic orgs, Mycoplasma and/or inhibition of normal vaginal flora
o 10% KOH with vag secretions  fishy odor secondary to release of amines
o Microscopic exam (3 of 4 necessary): (1) thin, white vag d/c (2) vag pH >4.5 (3) clue cells (4) pos whiff test
o Tx: Metro po BID x 7d, Clinda cream x 7d, Metro gel x 5d
* Candida albicans
o Thick, cheesy vaginal discharge usually associated with vulvar irritation and itching
+ Vaginal discomfort, burning, dyspareunia and external dysuria
o Dx: yeast or pseudohyphae on wet prep or gram stain
o Tx: single oral dose of fluconazole (150mg) or OTC antifungal vaginal creams, tablets or suppositories x 1-7 days (butoconazole, clotrimazole, miconazole and terconazole)
References

Update on Infections .ppt

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HUMAN PAPILLOMA VIRUS (HPV)

HUMAN PAPILLOMA VIRUS (HPV)
By: Nathalia Cruz

What is a Virus?
* Exceptionally simple living microbes.
* Contain a single type of nucleic acid (DNA or RNA) and a protein coat.
* Obligatory intracellular parasites.
* Range from 20 to 14.000 nm in length.
* It’s classification is based on type of nucleic acid, strategy for replication, and morphology

HUMAN PAPILLOMA VIRUS
* HPV is the virus that causes warts.
* More than 100 different kinds, 30-some of this cause genital HPV.
* Spread by sexual contact or from mother to baby.
* Genital warts appear 6 weeks to 8 months after contact with an HPV infected person.
* The most common sexually transmitted disease worldwide.
* Certain types of HPV are linked with cervical cancer.
* Divided into 2 subcategories: Genital Warts and Cervical Dysplasia.
* Most people do not know they have it.
* There are high risk and low risk types of it.

HISTORY
* The papillomaviruses are part of the PAPOVAVIRIDAE family of DNA tumor viruses.
* First discovered in the early 40’s.
* Gained notoriety in the early 80’s when it was discovered that some types of HPV caused cervical cancer.

MORPHOLOGY
* Papilloma virus genome is circular covalently closed double stranded DNA of about 8 kbp.
* All PV genes are coded in one of the 2 DNA strands utilizing the alternative splicing for the individual expression of each gene.
* Papillomavirus expression is characterized by a large array of mRNAs cells coding for different genes.
* 55 nm in diameter.

MECHANISM OF INFECTION
* All PV exhibit extreme specificity for infection on epithelial cells.
* The papillomavirus epitheliotrophy resides in the interaction of specific transmission factors with the viral regulatory region LCR.
* The infection normally results in hyperproliferation of the host cell and may lead to transformation and immortalization.

GENITAL WARTS
* Sometimes called condylomata acuminata.
* Are soft, moist or flesh colored, and appear in the genital area within weeks or months after infection.
* Sometimes appear in clusters and are either raised or flat, small or large.
* Women: appear in the vulva, cervix, vagina and anus.
* Men: Can appear on the scrotum or penis.

LIFE CYCLE (HPV-16)
* Starts with the infection of the host cell.
* The virus DNA is released within the nucleus
* Numerous cellular transcription factors interact with the non-coding viral regulatory region (LCR), starting transcription of the two hpv-16 transforming early genes (E6 and E7).
* The transforming proteins interact with the cellular antioncogenic regulator p53 disrupting the cell cycle.

HPV TYPES
* Numbered in order of discovery.
* 30 HPV types primarily infect the squamous epithelium of the lower anogenital tracts of both males and females.
* HPV types 6, 11, 42, 43, or 44 present as papillary condylomas, may also present as flat lesions that may or may not be visible to the unaided eye are part of the “low-risk” HPV types.
* Types 16, 18, 31, 33, 35, 45, 51, 52, and 56 are considered “high-risk” types because they have been found in cervical and other lower genital tract cancers.

HPV GENOMIC ORGANIZATION
* Three main regions (early, late and the long control region)
* (E) resides the transformation and immortalization potential.
* (L) Two capsid genes.
* (LCR) contains all the cis-regulatory elements.

HOW HPV CAUSES CANCER
* HPV DNA integrates into the host genome.
* The proteins E6 and E7 are produced from the resultant DNA.
* E6 binds and degrades p53 (a tumor suppressor gene).
* If the DNA is altered, the cell keeps replicating. The mutation rate of the cell increases.
* E7 binds and degrades retinoblastoma (another tumor suppressor gene).
* Retinoblastoma normally keeps the cell from growing too fast or responding to growth stimulators. This inhibitory factor is now lost.
* without these two mechanisms to slow down cell growth and prevent mutation. . .
* Malignant Transformation Occurs.

HPV TREATMENT
* Genital warts can be treated by a doctor and by different methods.
* Podofilox gel: A patient-applied treatment for external genital warts.
* Imiquimod cream: A patient-applied treatment.
* Chemical treatments (including trichloracetic acid and podophyllin), which must be applied by a trained health care provider to destroy warts.
* Cryotherapy: Uses liquid nitrogen to freeze off the warts.
* Laser therapy: Uses a laser beam or intense lights to destroy the warts.
* Electrosurgery: Uses and electric current to burn off the warts.
* Surgery: Can cut away the wart in one office visit .
* Interferon: an antiviral drug, which can be injected directly into warts.

CURE
* There is currently no cure for human papillomavirus.
* Once an individual is infected, he or she carries the virus for life even if genital warts are removed.
* The development of a vaccine against HPV is under way, but is still not available.
* If left untreated, some genital warts may regress on their own.

HUMAN PAPILLOMA VIRUS.ppt

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Protect yourself and Protect others! During this Flu Season

Protect yourself and Protect others!
During this Flu Season…

This module has been designed to provide information to the Duke Employees on seasonal and H1N1 Flu. After completing this module, you will be able to:

* Identify important facts related to seasonal and H1N1 Flu
* Describe proper hygiene practices and control measures, including vaccination to prevent
o Seasonal Flu and
o H1N1 Flu

* Describe the impact of the seasonal flu and H1N1Flu on employees and on Duke as an organization

Why Should I Be Concerned?

+ Typically, the” Flu” comes around yearly during the fall and early winter. This is considered the “seasonal” Flu and a vaccine is developed each year to provide protection against the most common strains that are expected to cause the most illness.
* Seasonal Flu is a serious disease. In fact, 25,000 to 35,000 die annually in the U.S. due to the seasonal Flu. Those at the highest risk for developing complications are:
o The elderly
o The very young
o Those with chronic medical conditions, such as heart disease, lung disease, diabetes or conditions that effect the immune system

Why Is This Year’s Flu Season Different?

+ This year, there is a new and very different Flu virus spreading worldwide called the H1N1 Flu or formerly known as the “Swine Flu”. Though this new type of Flu is turning out to be milder than originally feared, it can lead to complications.
+ At this time, many are susceptible to the H1N1 and those infected experience symptoms similar to the seasonal Flu. Those at highest risk for complications seem to be:
# Pregnant women
# Children
# Youth and young adults up to age 24
# Those with chronic medical conditions between ages 24 and 64

What Does This Mean For DU/DUHS?

Based on the government’s current estimate, 30-50% of our employees could be infected with the Flu this season.

Since we work closely together in the Duke community, we have many opportunities for contact.

Duke is taking steps to slow the spread of illness in the workforce.

Protecting yourself, your co-workers and your patients is the best way to decrease the impact of either the seasonal Flu or the H1N1 Flu. You’ll find out how in the next slides.


Remember that we all are susceptible to BOTH kinds of Flu.

To Protect Yourself & Prevent Spread . . .

It is important to know that the Flu is highly contagious, and spreads when the virus is passed from one individual to another individual. This can happen when an infected individual:

o Coughs, sneezes, or has direct physical contact with another individual
o Indirectly contaminates objects such as door knobs, telephones or surfaces. This is not the most common route of infection.

Remember that the virus can spread from the hands to eyes, nose, and mouth; so good hand hygiene is critical.

Here’s What You Can Do To Prevent Spreading The Virus . . .

+ Wash your hands. Washing hands often with soap and water or an alcohol-based hand cleaner will help protect against germs.
+ Cover your nose and mouth with a tissue when you cough or sneeze. Throw the tissue in the trash immediately after use. Wash your hands immediately.
+ If a tissue is not available, cough or sneeze into your elbow or sleeve.
+ Avoid touching eyes, nose or mouth. Germs are often spread when you touch something contaminated with germs and then touch your eyes, nose or mouth.
+ Stay home and away from others when you’re sick. You will help prevent others from getting sick.

And Take The Time To Get Vaccinated

* Too many employees unwisely continue to work while sick with the Flu.
* Unvaccinated workers who are not yet feeling sick can spread the virus.
* Infected individuals may be infectious the day before they become sick as well as after their fever is gone.

YOU maybe the source of Flu transmission!

Get Vaccinated for Seasonal Flu
The Center for Disease Control recommends a seasonal flu vaccine as the first and foremost important step in protecting against seasonal flu. Vaccination for seasonal Flu is vital for:

* Individuals at high-risk for serious Flu complications:
o The elderly
o The very young
o Those with chronic medical conditions, such as heart disease, lung disease, diabetes or conditions that effect the immune system
* Health care workers
* Individuals who live with or care for high-risk individuals
* All persons wishing to prevent seasonal flu


For more information, go to www.cdc.gov
Remember That DU/DUHS Offers Free
Seasonal Flu Vaccination

* Duke offers free seasonal flu vaccination to all employees.
* Times and locations of flu vaccination sites will be posted online at www.duke.edu/flu.
* Bring your Duke ID to receive the vaccination.
* If you have a fever, postpone your flu shot.

And Remember To Get Vaccinated for H1N1

* The seasonal Flu vaccine will not protect you against the H1N1 Flu.
* A separate vaccine is being developed for H1N1. It is expected to be available in late fall.
* The H1N1 vaccine will be distributed based on criteria as defined by the Centers for Disease Control (CDC).

How Do I Know If I Have The Flu?

Symptoms for both the Seasonal Flu and H1N1 Flu are similar . . .

o Fever of 100 degrees or more and any of these symptoms:
+ Cough
+ Sore throat
+ Runny or stuffy nose/sneezing
+ Body ache
+ Headache
+ Chills
+ Unusual fatigue

How Should I Care for Myself?

* Get Extra Rest
* Increase Fluid Intake
* Take Fever Lowering Medication (no aspirin for children)
* If you have severe illness or you are at high risk for flu complications, contact your health care provider or seek medical care.

Seek Urgent Medical Attention If You Experience . . .

Any of these emergency warning signs . . .

* Difficulty breathing or shortness of breath
* Pain or pressure in the chest or abdomen
* Sudden dizziness
* Confusion
* Severe or persistent vomiting

Protect yourself and Protect others!.ppt

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The Cardiovascular Examination

Valvular Heart Disease and the Cardiac Exam
By:Charlotte Bai, M.D.
Internal Medicine Board Review
May 28, 2009

Overview
* Clinical syndromes
* Overview of cardiac murmurs and maneuvers
* Left sided valvular lesions
o Aortic stenosis and sclerosis
o Mitral stenosis
+ Rheumatic fever prophylaxis
o Acute and chronic aortic regurgitation
o Acute and chronic mitral regurgitation
* Right sided valvular lesions
o Tricuspid valve disease
* Prosthetic valves
* Endocarditis prophylaxis
* Questions

General Appearance
* Marfan Syndrome
o Tall, long extremities
o Associated with: aortic root dilitation, MV prolapse
* Acromegaly
o Large stature, coarse facial features, “spade” hands
o Associated with: Cardiac hypertrophy
* Turner Syndrome
o Web neck, hypertelorism, short stature
o Associated with: Aortic coarctation, pulmonary stenosis
* Pickwickian Syndrome
o Severe obesity, somnolence
o Associated with: Pulmonary hypertension
* Fredreich ataxia
o Lurching gait, hammertoe, pes cavus
o Associated with: hypertrophic cardiomyopathy
* Duchenne type muscular dystrophy
o Pseudohypertrophy of the calves
o Cardiomyopathy
* Ankylosing spondylitis
o Straight back syndrome, stiff (“poker”) spine
o Associated with: AI, CHB (rare)
* Lentigines (LEOPARD syndrome)
o Brown skin macules that do not increase with sunlight
o Associated with: HOCM, PS
“Spade” hands in acromegaly
* Hereditary hemorrhagic telangiectasia (Osler-Weber-Rendu)
o Small capillary hemangiomas on the face or mouth
o Associated with: Pulmonary arteriovenous fistula
* Lupus
o Butterfly rash on face, Raynaud phenomenon- hands, Livedo reticularis
o Associated with: Verrucous endocarditis, Myocarditis, Pericarditis
* Pheochromocytoma
o Pale diaphoretic skin, neurofibromatosis- café-au-lait spots
o Associated with: Catecholamine-induced secondary dilated CM
* Sarcoidosis
o Cutaneous nodules, erythema nodosum
o Associated with: Secondary cardiomyopathy, heart block
* Tuberous Sclerosis
o Angiofibromas (face; adenoma sebaceum)
o Associated with: Rhabdomyoma
* Myxedema
o Coarse, dry skin, thinning of lateral eyebrows, hoarseness of voice
o Associated with: Pericardial effusion, LV dysfunction

Grading the Intensity of Cardiac Murmurs
* Grade 1
o Murmur heard with stethoscope, but not at first
* Grade 2
o Faint murmur heard with stethoscope on chest wall
* Grade 3
o Murmur hears with stethoscope on chest wall, louder than grade 2 but without a thrill
* Grade 4
o Murmur associated with a thrill
* Grade 5
o Murmur heard with just the rim held against the chest
* Grade 6
o Murmur heard with the stethoscope held away and in from the chest wall

Cardiac Murmurs


* Most mid systolic murmurs of grade 2/6 intensity or less are benign
o Associated with physiologic increases in blood velocity:
+ Pregnancy
+ Elderly
* In contrast, the following murmurs are usually pathologic:
o Systolic murmurs grade 3/6 or greater in intensity
o Continuous murmurs
o Any diastolic murmur

Diagnostic Testing
* ECHOCARDIOGRAM
Aortic Stenosis
Progression of Aortic Sclerosis
* Hemodynamic progression usually slow
o Average rate of increase in aortic jet velocity of 0.3 m/s per year
o Increase in mean transaortic gradient of 7 mmHg
o Decrease in AVA of 0.1 cm2 per year
* Severe AS
o Aortic jet velocity > 4 m/s
o Mean transvalvular pressure gradient > 50 mmHg
o AVA < 1.0 cm2

Pathophysiology of Aortic Stenosis
* Obstruction of LV outflow increases intracavitary systolic pressures and leads to LV pressure overload
* Initial compensatory mechanism is myocardial hypertrophy with preservation of systolic function
* Diastolic function impaired as a consequence of increased wall thickness and abnormal myocardial relaxation
* Increased wall stress and afterload causes eventual decrease in ejection fraction

Pseudostenosis
* Occurs in patients with impaired systolic function and aortic stenosis
o Unable to generate transvalvular gradient
* Careful diagnostic testing with dobutamine infusion protocols can aid in differentiating between true AS and pseudostenosis
* If the calculated AVA increases with augmentation of cardiac output, then pseudostenosis present
* If AVA does not increase with dobutamine, then obstruction fixed and true AS present

Clinical Presentation of Aortic Stenosis
* Cardinal symptoms:
o Angina
+ Occurs in >50% of patients, not sensitive due to prevalence of CAD
o Syncope
o CHF
* Sudden cardiac death rare, <1% per year
* In earlier stages, AS presentation more subtle
o Dyspnea
o Decreased exercise tolerance
* Rarely, AS diagnosed in the setting of GI bleeding
o Heyde’s syndrome
+ Bleeding caused by AVM
+ Concurrent AS occurs at prevalence rate of 15-25%
+ Associated with an acquired von Willebrand syndrome due to disruption of vW multimers through a diseased AV

Management of Aortic Stenosis
* Prognosis in asymptomatic disease excellent
* Conservative approach with monitoring for symptoms recommended
* When severe stenosis present-
o 38% of asymptomatic patients develop symptoms within 2 years
o 79% are symptomatic within 3 years
* Once symptoms occur, AVR needed
* LV dysfunction and severe AS have increased perioperative mortality with AVR
o But outcomes still favorable with surgery
* Nitroprusside may transiently improve cardiac function as a bridge to valve replacement
o Does not supplant AVR in symptomatic patients

Aortic Valve Replacement
* Prophylatic AVR in asymptomatic patients not routinely performed due to surgical risks
o Thromboembolism, bleeding associated with anticoagulation, prosthetic valve dysfunction, and endocarditis
o Occurs at a rate of 2-3% annually
o Only should be considered:
+ If other cardiac surgery (such as CABG) planned
+ Severe LVH or systolic dysfunction
+ Women contemplating pregnancy
+ Patients remote from health care
* Surgical valve replacement with operative morbidity and mortality of 10%
* Percutaneous balloon aortic valvotomy rarely used

Mitral Stenosis
* Usually associated with history of rheumatic fever
* >40% of cases of RHD result in mitral stenosis
o Women affected more than men (2:1)
* Presentation 20-40 years after the initial episode of rheumatic fever
o If infected at a young age, latent period is a few years

Clinical Presentation of Mitral Stenosis
* Significant MS leads to ↑LA pressure and pulm HTN
* Symptoms include dyspnea with ↑ cardiac demand
o Exercise
o Pregnancy
* Survival excellent with asymptomatic or minimally symptomatic patients
o >80% survival at 10 years
* Survival in symptomatic patients much worse
o 10 year survival drops to 15% or lower (if pulm HTN present)
* Findings consistent with severe MS:
o Transvalvular diastolic pressure gradient >10 mmHg
o MVA <1.0 cm2
o Severe pulmonary hypertension (>60 mmHg)

Management of Mitral Stenosis
* Atrial fibrillation
Mitral Valve Repair
* Percutaneous valvotomy
Rheumatic Fever Prophylaxis
* Primary prophylaxis
* Secondary prophylaxis
Acute Aortic Regurgitation
Acute Mitral Regurgitation
Chronic Valvular Regurgitation
Chronic Aortic Regurgitation
Chronic Mitral Regurgitation
Treatment of Chronic Mitral Regurgitation
Timing of Intervention for Left-Sided Valvular Conditions
OTHERWISE
Repeat TTE yearly, repeat clinical evaluation biannually
OTHERWISE
Repeat TTE at least yearly, repeat clinical evaluation at least biannually depending on the severity of the LV dilitiation
OTHERWISE
Clinical evaluation at least annually, depending on the severity of the mitral stenosis
OTHERWISE
Depending on the severity of AS, at least annual clinical evaluation with TTE to monitor for symptom onset
Intervention:
AVR
Chronic Severe MR
Chronic Severe AR
Mitral Stenosis
Aortic Stenosis
Tricuspid Valve Disease
* Tricuspid stenosis is rare
o Associated with rheumatic heart disease
* TR usually occurs secondary to:
o Pulmonary hypertension
o RV chamber enlargement with annular dilatation
o Endocarditis (associated with IV drug use)
o Injury following pacer lead placement
* Other secondary causes: carcinoid, radiation therapy, anorectic drug use, and trauma
* Primary causes: Marfan’s syndrome and congenital disorders such as Ebstein’s anomaly and AV canal malformation
* Echo is diagnostic in most cases
Tricuspid Regurgitation
* Severe tricuspid regurgitation is difficult to treat and carries a poor overall clinical outcome
* Symptoms are manifestations of systemic venous congestion
* Surgical intervention usually considered if other cardiac surgery planned
* Surgical options include valvular annuloplasty or replacement

Prosthetic Valves- Mechanical
* Three types:
o Ball-cage valve
o Single tilting disk valve
o Bileaflet valve
* Durable but require life long anticoagulation
* For operative procedures, warfarin typically is discontinued for 48-72 hours and restarted postop as soon as possible, except for:
o Mechanical mitral prosthesis
o Atrial fibrillation
o Prior thromboembolic events
Ball-cage valve
Single tilting disk valve
Bileaflet valve
Prosthetic Valves- Biological
* Biological Valves
o Composed of autologous or xenograft biological material mounted on stents and a sewing ring
o Warfarin therapy not required due to lower thromboembolic potential
o Valve durability less when compared to mechanical valves
o Newer stentless valves with increased longevity

Anticoagulation Guidelines for Mechanical Valves
Prosthetic Valve Complications
* Common complications include:
o Structural valve deterioration
o Valve thrombosis
o Embolism
o Bleeding
o Endocarditis
* Endocarditis prophylaxis required for patients with all types of prosthetic valves
* Suspect valve dehiscence or dysfunction in:
o Acute CHF in the immediate postop period
o New cardiac symptoms
o Embolic phenomena
o Hemolytic anemia
o New murmurs
* TEE is the diagnostic procedure of choice
* Postop TTE should be done 2-3 months after surgery

Valve Thrombosis
* Incidence with mechanical prosthesis of 2-4 % per year
* Suspect in patients with new murmur, change in cardiopulmonary symptoms, or an embolic event
* Diagnosis based on clinical presentation, TTE/TEE, and fluroscopy
* In small thrombus, treatment with heparin may be adequate
* Optimal treatment for left sided thrombosis is emergency surgery
* Consider thrombolytic therapy for right sided thrombosis or if surgery cannot be performed with left sided disease
Endocarditis Prophylaxis

The Cardiovascular Examination.ppt

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Heart Murmurs

Heart Murmurs
By: David Leder

Outline

I. Basic Pathophysiology
II. Describing murmurs
III. Systolic murmurs
IV. Diastolic murmurs
V. Continuous murmurs
VI. Summary

Basic Pathophysiology
Murmurs = Math
Describing a heart murmur

1. Timing
o murmurs are longer than heart sounds
o HS can distinguished by simultaneous palpation of the carotid arterial pulse
o systolic, diastolic, continuous
2. Shape
o crescendo (grows louder), decrescendo, crescendo-decrescendo, plateau

3. Location of maximum intensity
o is determined by the site where the murmur originates
o e.g. A, P, T, M listening areas
4. Radiation
o reflects the intensity of the murmur and the direction of blood flow

5. Intensity
o graded on a 6 point scale
+ Grade 1 = very faint
+ Grade 2 = quiet but heard immediately
+ Grade 3 = moderately loud
+ Grade 4 = loud
+ Grade 5 = heard with stethoscope partly off the chest
+ Grade 6 = no stethoscope needed

*Note: Thrills are assoc. with murmurs of grades 4 - 6

6. Pitch
o high, medium, low
7. Quality
o blowing, harsh, rumbling, and musical
8. Others:
i. Variation with respiration

+ Right sided murmurs change more than left sided

ii. Variation with position of the patient

iii. Variation with special maneuvers

+ Valsalva/Standing => Murmurs decrease in length and intensity

EXCEPT: Hypertrophic cardiomyopathy and Mitral valve prolapse

Systolic Murmurs
* Derived from increased turbulence associated with:

1. Increased flow across normal SL valve or into a dilated great vessel
2. Flow across an abnormal SL valve or narrowed ventricular outflow tract - e.g. aortic stenosis
3. Flow across an incompetent AV valve - e.g. mitral regurg.
4. Flow across the interventricular septum

Early Systolic murmurs
1. Acute severe mitral regurgitation
2. Congenital, small muscular septal defect
3. Tricuspid regurg. with normal PA pressures

Midsystolic (ejection) murmurs
* Are the most common kind of heart murmur
* Are usually crescendo-decrescendo
* They may be:
1. Innocent
2. Physiologic
3. Pathologic

Aortic stenosis
* Loudest in aortic area; radiates along the carotid arteries
* Intensity varies directly with CO
* A2 decreases as the stenosis worsens
* Other conditions which may mimic the murmur of aortic stenosis w/o obstructing flow:

1. Aortic sclerosis
2. Bicuspid aortic valve
3. Dilated aorta
4. Increased flow across the valve during systole

Hypertrophic cardiomyopathy
Pansystolic (Holosystolic) Murmurs
1. Mitral valve regurgitation
2. Tricuspid valve regurgitation
3. Ventricular septal defect
Diastolic Murmurs
* Almost always indicate heart disease
* Two basic types:

1. Early decrescendo diastolic murmurs
2. Rumbling diastolic murmurs in mid- or late diastole

Aortic Regurgitation
* Best heard in the 2nd ICS at the left sternal edge
* High pitched, decrescendo
* Blowing quality => may be mistaken for breath sounds
* Radiation:

Mitral Stenosis
* Two components:
1. Middiastolic - during rapid ventricular filling
2. Presystolic - during atrial contraction; therefore, it disappears if atrial fibrillation develops
Continuous Murmurs

1. Cervical venous hum
2. Mammary souffle
3. Patent Ductus Arteriosus
4. Pericardial friction rub
Back to the Basics
1. When does it occur - systole or diastole
2. Where is it loudest - A, P, T, M
I. Systolic Murmurs:
1. Aortic stenosis - ejection type
2. Mitral regurgitation - holosystolic
3. Mitral valve prolapse - late systole

II. Diastolic Murmurs:
1. Aortic regurgitation - early diastole
2. Mitral stenosis - mid to late diastole

Summary
A. Presystolic murmur
o Mitral/Tricuspid stenosis
B. Mitral/Tricuspid regurg.
C. Aortic ejection murmur
D. Pulmonic stenosis (spilling through S20
E. Aortic/Pulm. diastolic murmur
F. Mitral stenosis w/ Opening snap
G. Mid-diastolic inflow murmur
H. Continuous murmur of PDA

Heart Murmurs.ppt

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Valvular Heart Disease

Valvular Heart Disease

Medical Surgical I
Types
* Mitral Stenosis
* Mitral Regurgitation
* Mitral Valve Prolapse
* Aortic Stenosis
* Aortic regurgitation
* Tricuspid valve is affected infrequently
o Tricuspid stenosis – causes Rt HF
o Tricuspid regurgitation –causes venous overload

Tricuspid Valve
Rheumatic Heart Disease
* Inflammatory process that may affect the myocardium, pericardium and or endocardium
* Usually results in distortion and scarring of the valves
* Subjective symptoms
o Prior history of rheumatic fever
o General malaise
o Pain – may or may not be present
* Objective symptoms
o Temperature
o Murmurs
o Dyspnea
o polyarthritis
* Diagnosis
o H/P
o WBC and ESR
o C-reactive protein
o Cardiac enzymes
o EKG
o Chest x-ray
o Echo
o Cardiac cath
o Cardiac output
* Nursing Care
o Vital signs
o Rest and quiet environment
o Give antibiotics, digitalis, and diuretics
o Provide adequate nutrition
o Monitor I/O
o Explain treatment and home care

Mitral Stenosis
* Usually results from rheumatic carditis
* Is a thickening by fibrosis or calcification
* Can be caused by tumors, calcium and thrombus
* Valve leaflets fuse and become stiff and the cordae tendineae contract
* These narrows the opening and prevents normal blood flow from the LA to the LV
* LA pressure increases, left atrium dilates, PAP increases, and the RV hypertrophies
* Pulmonary congestion and right sided heart failure occurs
* Followed by decreased preload and CO decreases
* Mild – asymptomatic
* With progression – dyspnea, orthopneas, dry cough, hemoptysis, and pulmonary edema may appear as hypertension and congestion progresses
* Right sided heart failure symptoms occur later
* S/S
o Pulse may be normal to A-Fib
o Apical diastolic murmur is heard

Mitral Regurgitation
* Primarily caused by rheumatic heart disease, but may be caused by papillary muscle rupture form congenital, infective endocarditis or ischemic heart disease
* Abnormality prevents the valve from closing
* Blood flows back into the right atrium during systole
* During diastole the regurg output flows into the LV with the normal blood flow and increases the volume into the LV
* Progression is slowly – fatigue, chronic weakness, dyspnea, anxiety, palpitations
* May have A-fib and changes of LV failure
* May develop right sided failure as well

Mitral Valve Prolapse
* Cause is variable and may be associated with congenital defects
* More common in women
* Valvular leaflets enlarge and prolapse into the LA during systole
* Most are asymptomatic
* Some may report chest pain, palpitations or exercise intolerance
* May have dizziness, syncope and palpitations associated with dysrhythmias
* May have audible click and murmur

Aortic Stenosis
* Valve becomes stiff and fibrotic, impeding blood flow with LV contraction
* Results in LV hypertrophy, increased O2 demands, and pulmonary congestion
* Causes – rheumatic fever, congenital, arthrosclerosis
* Atherosclerosis and calcification is primary cause in the elderly
* Complications – right sided heart failure, pulmonary edema, and A-fib
* S/S – Early: dyspnea, angina, syncope

Aortic Regurgitation
* Aortic valve leaflets do not close properly during diastole
* The valve ring that attaches to the leaflets may be dilated, loose, or deformed
* The ventricle dilates to accommodate the ^ blood volume and hypertrophies
* Causes: infective endocarditis, congenital, hypertension, Marfan’s
* May remain asymptomatic for years
* Develop dyspnea, orthopnea, palpitations, ,and angina
* May have ^ systolic pressure with bounding pulse
* Have a high pitch, blowing, decrescendo diastolic murmur

Assessment for Valve Dysfunction
* Subjective symptoms
o Fatigue
o Weakness
o General malaise
o Dyspnea on exertion
o Dizziness
o Chest pain or discomfort
o Weight gain
o Prior history of rheumatic heart disease
* Objective symptoms
o Orthopnea
o Dyspnea, rales
o Pink-tinged sputum
o Murmurs
o Palpitations
o Cyanosis, capillary refill
o Edema
o Dysrhythmias
o Restlessness

Diagnosis
* History and physical findings
* EKG
* Chest x-ray
* Cardiac cath
* Echocardiogram

Medial Treatment
* Nonsurgical management focuses on drug therapy and rest
* Diuretic, beta blockers, digoxin, O2, vasodilators, prophylactic antibiotic therapy
* Manage A-fib, if develops, with conversion if possible, and use of anticoagulation

Interventions
* Assess vitals, heart sounds, adventitious breath sounds
* ^ HOB
* O2 as prescribed
* Emotional support
* Give medications
* I/O
* Weight
* Check for edema
* Explain disease process, provide for home care with O2, medications

Surgical Management of Valve Disease
* Mitral Valve
o Commissurotomy
o Mitral Valve Replacement
o Balloon Valvuloplasty
* Aortic Valve Replacement

Mechanical Valve
Porcine Valve
Tissue Valve

Valvular Heart Disease.ppt

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Developmental Toxicology

Developmental Toxicology

* Structural malformations
* Growth retardation
* Functional impairment
* Death of the organism
4 manifestations of developmental toxicity

Teratology
1. the study of malformations or serious deviations from the normal type in organisms

2. the branch of science concerned with the production, development, anatomy, and classification of malformed fetuses.

* Teratogen
o Any agent that causes a birth defect
o After Greek “monster creating”
* Environmental conditions (1200)
* Maternal nutritional deficiencies (1930)
* Rubella virus infection (1941)
* Thalidomide (1961)

Adverse Outcomes in Pregnancy
Cause of human birth defects
Chemical teratogenicity
Pregnancy Risk Categories
Therapeutic Drugs Teratogenic to Humans
* Anticonvulsants
o Phenytoin, primidone, trimethadione, valproic acid, carbamazepine
* Anticancer agents
o Alkylating agents –busulfan, cyclophosphamide, chlorambucil, mechlorethamine
o Antimetabolites-aminopterin, methotrexate, cytarabine
* Androgenic hormones-danazol
* Coumarin anticoagulants-warfarin
* Retinoids-accutane, isotretinoin, etretinate, acitretin
* Antihyperlipidemic agents-lovastatin, atorvastatin
* Other drugs-diethystilbestrol, thalidomide, penicillamine, lithium, fluconazole, misoprostol
Thalidomide
Diethylstilbesterol (DES)
Alcohol (Ethanol)
Fetal Alchohol Syndrome (FAS)
Fetal Alchohol Effects (FAE)
* Cranial facial dysmorphism
* Intrauterine and postnatal growth retadation
* Retarded psychomotor and intellectual development
* IQ 68

Tobacco smoke
* Spontaneous abortions
* Perinatal deaths
* Lower birth weight
* Increased risk of
o Sudden infant death syndrome
o Behavioral attention disorders
o Orofacial cleft (particular xenobiotic gene polymorphisms)
o Gastroschisis (with variant alleles N053, ICAM1, NPPA)
o Branching morphogenesis and maturation of the lung
* Nicotine-related adverse nerodevelopmental outcomes
Cocaine
* At risk for premature labor, spontaneous abortion, increased perinatal mortality and fetal death.
* intrauterine growth retardation, microcephaly, altered presencephalic development, decreased birth weight, a neonatal neurologic syndrome of abnormal sleep, tremor, poor feeding, irritability, and occasional seizures.
* Genitaouinary tract malformation
* Impaired uditory process

Retinoic Acid
Retinoic acid is the active ingredient in “Accutane”, a drug used to treat severe acne. Since its introduction in September of 1982, an estimated 160,000 women of child bearing age have ingested the drug. Between 1982 and 1987, approximately 900-1300 malformed children, 700-1000 spontaneous abortions and 5000-7000 elective abortions are due to Accutane exposure. Exposed children may have hydrocephaly, ear malformations, cardiovascular defects and decreased IQ. Accutane carries a pregnancy category X warning, meaning it is a known human teratogen.
c acid
Retinoids
* Malformations of the face, limbs, heart, CNS, and skeleton
* RXR α receptor
* Schizophrenia
Retinoid Therapies
Tretinoin/ATRA (Vesanoid)
Leukemia
Adapalene (Differin),
Tretinoin (Renova),
Isotretinoin (Accutane)
Acne
Tazartene (Zorac),
Etritinate (Tegison)
Psoriasis
Drugs
RAR and RXR (Simple Version)
* Nuclear Receptors (like ER, PPAR, VDR and others)
* RXR/RAR Heterodimer is functional unit
* Bind selectively to REs in genome
* Act as transcription factors
* Up-regulate or Repress the expression of particular genes

Valproic acid was released in 1967 in Europe and in 1978 in the United States to treat epilepsy. Approximately 11,500 epileptic women become pregnant each year, many of which use valproic acid. By 1980, publications began linking malformed children to in utero exposure to valproic acid (greater than 500 mg/day).

Valproic Acid
* spina bifida with menigomyelocele or menigocele
* The proposed mechanism of action is that valproic acid influences folate metabolism

Angiotensin Converting enzyme inhibitors and angiotensin antagonists
* 2-3 trimester
* related reduced amniotic fluid volume and impaired fetal renal function
o Oligohydromnios
o Fetal growth retardation
o Pulmonary hypoplasia
o Renal failure
o Hypotension
o Death
* First trimester
o Congenital malformation

Wilson’s General Principles of Teratology (Table 10-2)
* Susceptibility to teratogenesis depends on the genotype of the conceptus and the manner in which this interacts with environmental factors.
* Susceptibility to teratogenic agents varies with the developmental stage at the time of exposure.
* Teratogenic agents act in specific ways (mechanisms) on developing cells and tissues to initiate abnormal embryogenesis (pathogenesis).
* The final manifestations of abnormal development are death, malformation, growth retardation, and functional disorder.
* The access of adverse environmental influences to developing tissue depends on the nature of the influences (agent).
* Manifestations of deviant development increase in degree as dosage increases from the no-effect to the totally lethal level.
Critical periods of susceptibility and endpoints of toxicity
* Gametogenesis and Fertilization

Mechanism unclear, may be related to imprinting
Cytosine methylation and change in chromatin conformation ethylene oxide, ethylmethane sulfonate, ethylnitrosourea→malformed fetus

DNA Methylation vs Genomic Imprinting
Mechanisms and pathologenesis of developmental toxicology

* Mutations
* Chromosomal breaks
* Altered mitosis
* Altered nucleic acid integrity or function
* Diminished supplies or precursors of substrates
* Decreased energy supplies
* Altered membrane characteristics
* Osmolar imbalance
* Enzyme inhibition
Example of cyclophosphamide (CP)
Single strand DNA break
A teratogenic chemotherapeutic agent
CP induces DNA damage
Advances in the Molecular basis of dysmorphogenesis
1.Using either singly or double gene knockout Retinoic acid receptor family (syndactyly)
2. Antisense oligonucleotide Wnt-1, Wnt-3a (mid and hindbrain malformation)
3. Reporter transgenes

Pharmacokinetics and metabolism in pregnancy
1.Changes in maternal physiology
hepatic metabolism, GI tract, cardiovascular system, excretory system, respiratory system
2.Overall decrease in hepatic xenobiotic transformation
3.Roles of placenta in influence embryonic exposure help to regulate blood flow
-offer a transport barrier-pH gradient, weak acid rapidly transfer
-metabolize chemicals
2-acetylaminofluorene (proteratogen)
7-hydroxyl metabolites(proximate teratogen)
4.Maternal metabolism of xenobiotics 2-methoxyethanol 2-methoxyacetic acid

Placental toxicity
* Metals, Cd, As, Hg, ethanol, cocaine, cigaratte, sodium salicylate
* Maternal injection vs fetal injection of Cd
* Production of metallothionein
* Interaction with Zn

Maternal toxicity-
* acetazolamide inhibits carbonic anhydrase forelimb ectrodactyly

* diflunsial results in anemia skeleton defects in rabbits
* phenytoin affects folate metabolism and heart rates
* metallothionein synthesis inducer-urathane, mercaptopurine, valproic acid Zn deficiency

Develpmental toxicity of endocrine-disrupting chemicals
Definition of endocrine-disrupting chemicals
“Exogenous agent that interferes with the production, release, transport, metabolism, binding, action, or elimination of natural hormones responsible for the maintenance of homeostasis and the regulation of developmental processes.”
Endocrine-disrupting chemicals
Four modes of action
1. Serving as steroid receptors ligands
2. Modifying steroid hormone metabolizing enzymes
3. Perturbing hypothalamic-pituitary release of trophic hormones
4. Uncharacterized proximate modes of action

Fetal Basis and Transgenerational Transmission of Reduced Fertility
Environmental Epigenetics
Decreased spermatogenic capacity and decreased fertility ..as well as increased prevalence of other diseases transferred via MALE germ line

Summary
* A transient embryonic exposure to endocrine disruptors at the time of gonadal sex determination can cause epigenetic transgenerational disease state of subfertility and spermatogenic defects in F1 through F4 generations
* Transgenerational disease phenotype was primarily transmitted through the male germ line
* Exposure appears to have caused an epigenetic reprogramming of the germ cell line that is “permanent” and transferred transgenerationally to subsequent generations

Modern safety assessment
* Regulatory guidelines for in vivo testing
* Multigeneration tests
* Children’s health and the food quality protection act
o Tenfold safety factor for children
* Alternative testing strategies
* Epidemiology
* Concordance of data (among species)
* Elements of risk assessment
use-in pregnancy rating: A, B, C, D, X

In Vivo Regulatory Protocol Guideline
The 17 intercellular signaling pathways by most metazoans
* Early development and later
* 1. Wnt pathway
* 2. Receptor serine/threonine kinase (TGFb) pathway
* 3. Hedgehog pathway
* 4. Receptor tyrosine kinase (small G proteins) pathway
* 5. Notch/Delta pathway
* Mid-development and later
* 6. Cytokine receptor (cytoplasmic tyrosine kinases)
* pathway
* 7. IL1/Toll NFkB pathway
* 8. Nuclear hormone receptor pathway
* 9. Apoptosis pathway
* 10. Receptor phosphotyrosine phosphatase pathway
* Larval/adult physiology
* 11. Receptor guanylate cyclase pathway
* 12. Nitric oxide receptor pathway
* 13. G-protein coupled receptor (large G proteins) pathway
* 14. Integrin pathway
* 15. Cadherin pathway
* 16. Gap junction pathway
* 17. Ligand-gated cation channel pathway

Sonic Hedge-hog signal pathway
cyclopamine
jervine
Holoprosencephaly
Cholesterol synthesis inhibitor
Consequences of Folate Deficiency
* Result of low dietary intake, genetic error of folate metabolism, lifestyle exposures
* DNA Hypomethylation
o Gene overexpression, uncontrolled cell growth, genomic instability
* Hyperhomocysteinemia
o Excessive accumulation of Hcy
* Base Misincorporation
o Decrease in thymine synthesis; replaced by uracil
o DNA strands prone to nicks, breaks and vulnerable to mutagen insertion
Homework

1. Describe the possible mechanisms for teratogenic effects of the following chemicals.
a. aminoglycosides
b. ethylene oxide
c. captopril
d. danazol
e. aminopterin
f. Accutane

Developmental Toxicology.ppt

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Forensic Anthropology

Forensic Anthropology
Why Forensic Anthropology

* Forensic pathologists are trained to analyze soft tissue and organs. Their experience with hard tissue (bone) is limited.
* The forensic anthropologist specializes in hard tissue morphology, structure and variability. In those cases in which soft tissue has been degraded by time, temperature, environment or other external forces, the only tissue remaining more or less intact is bone.
* Physical Anthropologists and Archeologists study human remains-and have become part of solving crimes.

What Questions Can Forensic Anthropology Answer?

* What is the race of the individual?
* What is the sex of the individual?
* What is the age of the individual?
* What is the stature of the individual?
* What pathologies did the individual have?
* What traumas did the individual have?
* What individual traits did the individual have?

Identity of Decomposed or Skeletal Remains

* Are the remains human or animal? (butchers remains and skeletal remains of dead pets etc. may be found in unlikely places)
* Are they really bones? (wood, stones)
* Are they human?
* How many bodies?
* How long dead? - recent or ancient (e.g. construction or digging at an old burial site)
* Cause of death?
How does this Work?

* Forensic anthropologists use regression equations to determine sex, age, stature, and race of skeletal remains.
* Regression equations are mathematical equations developed from studies of bones of individuals of known sex, age, race, and stature, and are used to predict such things of even fragmentary skeletal remains."

Sex Estimation
* The sex of an individual is determined, when soft tissue is not present, by a number of skeletal indicators.
* The more indicators used to determine sex, the more accurate the results.
* A forensic anthropologist is analytically limited by the bones present and the condition of the bones.
* In general, the muscles in a man are stronger and more developed than in a woman.
* Bones of men are larger and more robust than bones of women.
* Some bones display specific features which can be used to help determination of the sex of the skeleton. The best indicators are the:
o Skull
o Pelvis
o Head of the Femur
Sex Estimation – Adult
* Usually related to size in adult long bones
* Male bones: usually larger, longer in a single population – be cautious if different populations are involved
* Maximum diameter of head of humerus and head of femur may be used (Bass).
* Much more difficult to estimate sex in children’s skeletons.
Sex Estimation: Skull

* Good area for sex determination
* Generalization: male skull more robust, muscle-marked than female: ABSOLUTE
* DIFFERENCES SELDOM EXIST (Bass)
* Sex estimation: face, mandible, vault

Sex Estimation: Face
1. Supraorbital (Brow) ridges: more prominent in males
2. Superior orbital margin: sharper in females
3. Palate: larger in males
4. Teeth: larger in males (Bass)
5. Mastoid process: more prominent and rugged in males.
6. Orbit (Eye socket): Rounder in females, more rectangular in males
7. Chin: more pronounced in males and larger jaws.

Pelvis
* Women give birth. For this reason, the pelvis of a woman is larger than the pelvis of a man.
* The pelvis of a woman is wide and circular whereas the pelvis of a man is narrow and heart-shaped.
* Two angles, the sub-pubic angle and the sciatic notch, cause the differences in the shape of the pelvis.
* In women, the sub-pubic angle and sciatic notch are wide. In men, the sub-pubic angle and sciatic notch are narrow.

Male Pelvis Subpubic Notch
Female Pelvis Subpubic Notch
Pubis Bone Traits Related to Sex
Subpubic angle (degrees) angle made by the inferior borders of the articulated pubis bone
Pubis body width (mm)
Ventral arc: a roughened projection of bone visible on the anterior surface of the pubis bone
Head of the Femur
* In men, the diameter of the head of the femur is larger than 51 mm.
* In women, the diameter of the head of the femur is less than 45 mm.

Determining Ages of Skeletons
* Bone growth stops at about 20 yrs. of age in humans.
* Adult bone continuously adapts to prevailing stresses by appropriate deposition and resorption.
* Deposition and resorption are under hormonal control - integrated with regulation of blood calcium levels.
Skeletal Age
* Skeletal age is the estimated age at which a person died. Skeletal age can be determined by looking at the following:
o sutures of the skull
o teeth
o ribs
o vertebrae
o growth areas of the long bones: epiphyses
Sutures of the Skull
* When a baby is born, the skull is still growing.
* To accommodate this growth, the different bones of the skull are separate.
* By the age of 7, all the different bones have finished growing and the fontanelles have disappeared.
Skull Sutures

The Teeth
* The teeth are arranged in upper and lower arches. Those of the upper are called maxillary; those of the lower are mandibular.

Dental Tissues.
* Enamel. The protective outer surface of the anatomic crown. It is 96% mineral and is the hardest tissue in the body.
* Dentin. Located in both the crown and root, it makes up the bulk of the tooth beneath the enamel and cementum. It lines the pulp cavity.
* Cementum. This substance covers the surface of the anatomic root.
* Pulp. The central, innermost portion of the tooth. It has formative, sensory, nutritive, and functions during the life of the tooth.

* There are four types of teeth with very different shapes:
* Incisors (2)
* Canines (1)
* Premolars (bicuspids) (2)
* Molars (2-3)
* Individual teeth are quite distinct, even when lost from a jaw.

Dental Formula (from the midline)

* Primary (deciduous) teeth.
* It is said as: incisors, two upper and two lower; canines, one upper and one lower; molars two upper and two lower equals ten per side.
* Permanent teeth.
* It is said as: incisors, two upper and two lower; canines, one upper and one lower; premolars, two upper and two lower; and molars, three upper and three lower.

Teeth
* The first teeth to appear are the incisors, which are followed by canines and molars.
* When chewing food, teeth grind down.
* Comparing different teeth gives an idea of how long the teeth have been used.
* Eventually teeth may be lost, due to caries or attrition.

X-Rays Are Used to Date Skulls
* This is the side view of the dentition of a six year old boy.
* There is still some variation from person to person in the order in which the teeth erupt.

Baby Teeth Permanent Teeth
Dental Disease - Cavities, Abscesses, and Attrition
Ribs
* Because of breathing, the front part of the ribs is constantly moving.
* As a person gets older, the front part of the ribs begin to change and form bony spikes.
Vertebrae
* As a person gets older, bony spikes can also start growing on the vertebrae.
* This starts at approximately 40 years of age.
Growth areas of the long bones
(epiphysis)
* From birth to ą25 years of age, a person grows at a relatively constant rate.
* Growth takes place at the ends of the long bones.
* At a certain age, growth is completed and this can also be seen on the bone.

Epiphyseal Fusion
* The pattern of fusion of bone ends (epiphysis) to bone shaft (metaphysis) in each bone indicates age.
* Charts & tables are used.
* The upper arm stops growing at the shoulder at approximately age 20 and at the elbow at approximately age 14.5.
* The upper leg stops growing at the hip at approximately age 17.5 and at the knee at approximately age 18.

Determining Ages of Skeletons
* Cranial suture fusion is less reliable.
* Pubic symphysis changes slightly with age.
* Arthritic changes and osteoporosis give further clues.

Arthritic changes and osteoporosis give further clues to the ages of skeletons.
Ossification Centers
* Useful only in fetuses and babies.
* May be determined radiologically or by cutting into ossification centers.
* May be confirmed histologically.
* Most important center in medico-legal work is the distal center of the femur.
* This is present at birth and indicates a full term baby.
Age Determination from Skeleton
* Long bone length (femur, tibia, humerus) is proportional to height.
* Tables are used.
* Fairly reliable up to the age of epiphyseal fusion.
* There are sex, race, nutrition and personal variations to consider.
Individual Characteristics
Fractures
Head Injuries
Individual Characteristics
* Bone disease (Paget's disease, tumors)
* Previous injury to bone (fracture callus, prosthesis, metallic fragments).
* Comparison of trabecular pattern of bone.
* Pattern of skull's frontal air sinuses. Outline is unique and comparisons with clinical X-rays are useful.
Forensic Dentistry
* Teeth are commonly used to establish identity of deceased.
* Dental X-rays and dental casts are available often for 10 years after a patient visits the dentist last..
Height
Body Type
Race or Ethnic Group Determination
Minimum Number of Individuals
Dating of Human Skeletal Remains
Age of Human Remains
* Naked eye appearance is unreliable:
* Tags of soft tissue, periosteum, ligaments etc, indicate less than 5 years old.
* Soapy texture of surface indicates age less than a few decades.
* Light, crumbling bones are likely to be a century or more old.

Laboratory Tests Can Help
* Immunological reaction between bone extract and anti human serum ceases within months of death.
* If blood pigments are present bones are usually less than 10 years old.
* Up to 20 amino acids may be identified in bones less than a century old.
* Fluorescence of freshly sawn bone surface under UV light diminishes after 100 years.
* New bones contain 4.0 - 4.5 gms% nitrogen; 2.5 gms% indicates approximately 350 years.
* Radioactive carbon dating indicates which century.
Taphonomy
* Coined from the Greek words taphos, for "burial," and nomos, for "law."
* Forensic Taphonomy : The Postmortem Fate of Human Remains
* Skeletal trauma, decomposition, and dispersal of remains.
* Weathering, a taphonomic process, is very useful in determining the elapsed time since death.
Facial Reconstruction
* Skull can be scanned into a computer and "fleshed" by computer reconstruction to give likely facial appearance in life.
* Unfortunately eye color, hair color and lips are independent of bony structure.
* Pearl was a female who died in her early forties approximately three hundred years ago.
* She was Caucasian, of European ancestry and stood about 5'1".
* Her dental health was extremely poor and she had lost 63 per cent of her teeth prior to death. She had no teeth on either side of her jaw. This was most important as the loss of those teeth would evidence themselves in the final reconstruction as sunken cheeks. Of her remaining teeth, the condition was poor and she had several abscesses.
* During her lifetime, there are indicators that she also suffered from acute infections, rickets, sinusities, an upper respiratory infection, arthritis, and gout. Whew--all this in an era when aspirin didn't exist!
* On the other hand, it was determined that she was very muscular, as the ridges on her long bones were very developed.

Various items (glasses, clothing, hats) may be applied to better accentuate the features of the individual.
This method can be very successful.
Cause of Death
* Anthropologists can distinguish between marks from the result of a weapon attack and those resulting from the gnawing and biting of bones by scavenging animals.
* They can also determine the exact kind of weapon and animal, and they can tell if a wound is old or if it occurred at death.
* They can be called upon to testify as to the type of weapon used (saw vs. knife).

Lizzie Bordon’s Father’s skull: Ax Whacked.

* Two outstanding cases of the use of forensic anthropology to successfully solve unsolved mysteries are the cases of Francisco Pizarro.

Pizarro conquered the Incas.
* Pizarro was hated by the Peruvians because he was a brutal ruler. On June 26, 1541 (at age 66), he was stabbed to death by a crowd of angry subjects and in view of many witnesses (Dickerson 1993).
* His brutal death is not questioned due to the well documentation at the time. It was his remains that were questioned.
* In the 1890's, Peruvian officials decided to put Pizarro's remains on exhibit. "They asked officials at the Cathedral of the Plaza de Aramis in Lima for Pizarro's body and were directed to a mummy, which they put on view." (Dickerson 1993)
* In 1978 workers discovered a secret niche that had been walled over in the cathedral, and on a shelf in the niche was a box with a skull and an inscription that identified it as the head of Pizarro.
* Another box was found containing the bones of several unidentified individuals (Dickerson 1993).

* An investigation of the bones in the second box led to the discovery that the postcranial bones matched the skull in the first box.
* These bones and the skull were then placed together and prepared for study to determine if they had marks consistent with sword or knife wounds.

Forensic Anthropology.ppt

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Vitamins

Definition and Classification
* Non-caloric organic nutrients
* Needed in very small amounts
* Facilitators – help body processes proceed; digestion, absorption, metabolism, growth etc.
* Some appear in food as precursors or provitamins

Definition and Classification
* 2 classes, Table 7.1
o Fat soluble:
o Water soluble:
* Fat soluble vitamins
o Found in the fats and oils of food.
o Absorbed into the lymph and carried in blood with protein transporters = chylomicrons.
o *Stored in liver and body fat and can become toxic if large amounts are consumed.
* Water soluble vitamins
o Found in vegetables, fruit and grains, meat.
o Absorbed directly into the blood stream
o Not stored in the body and toxicity is rare. Alcohol can increase elimination, smoking, etc. cause decreased absorption.

Fat Soluble Vitamins
* Vitamin A (precursor – beta carotene)
o 3 forms: retinol (stored in liver), retinal, retinoic acid
o Roles in body:
+ Regulation of gene expression
+ Part of the visual pigment rhodopsin, maintains clarity of cornea (yes eating carrots is good for your eyesight)
+ Required for cell growth and division - epithelial cells, bones and teeth
+ Promotes development of immune cells, especially “Natural Killer Cells”
+ Antioxidant
* Vitamin A
o Deficiencies cause:
+ Night blindness, xerophthalmia (keratin deposits in cornea), macular degeneration.
+ Skin and mucous membrane dryness and infection, keratin deposits.
+ Anemia
+ Developmental defects – bones, teeth, immune system, vision

o Toxicities (RetinA/Accutaine, single large doses of supplements, eating excessive amounts of liver) cause:
+ Fragile RBCs, hemorrhage
+ Bone pain, fractures
+ Abdominal pain and diarrhea
+ Blurred vision
+ Dry skin, hair loss
+ Liver enlargement
o DRI: 700(women)-900(men) micrograms/day, UL 3000 micrograms
o Sources, see snapshot 7.1

* Vitamin D – precursor is cholesterol, converted by UV from sunlight exposure, therefore is a “non-essential” vitamin.
o Roles:
+ Increases calcium absorption in bone, intestines, kidney. Promotes bone growth and maintenance.
+ Stimulates maturation of cells – heart, brain, immune system, etc.

o Deficiencies: rickets (children), osteomalacia (adults). What are some of the causes of deficiencies?
o Toxicities (5X DRI)
+ Loss of calcium from bone and deposition in soft tissues.
+ Loss of appetite, nausea and vomiting, psychological depression.

Bowed legs – Characteristic of rickets

Beaded ribs – Characteristic of rickets
* Vitamin D
o DRI – 5 micrograms/day for ages 19-50, 10 for ages 51-70, 15 for ages >70.
o Sources, see snapshot 7.2

Fat Soluble Vitamins
* Vitamin E – tocopherol, *alpha-, beta -, gamma-, and delta-
o Roles:
+ Antioxidant (protects polyunsaturated fats)
+ Prevention of damage to lungs, RBCs, WBCs (immunity), heart
+ Necessary for normal nerve development
* Vitamin E
o Deficiencies (decreased absorption of fats- liver disease, low fat diets)
+ Premature babies – fragile RBCs (hemolysis)
+ Loss of muscle coordination, vision, immune functions
o Toxicities (more than 1000 milligrams/day)
+ Increases the effects of anticoagulants (Coumadin, Warfarin)
o DRI 15 milligrams/day (alpha-tocopherol)
o Sources, see snapshot 7.3
* Vitamin K – produced by bacteria in large intestine
o Roles
+ Promotes synthesis of blood clotting proteins (**Interferes with Coumadin)
+ Bone formation
o Deficiencies are rare but seen in infants, after prolonged antibiotic therapy, and in patients with decreased bile production.
o Toxicities (>1000 mg/day): rupture of RBCs and jaundice

o DRI: 90(women) – 120(men) micrograms/day
o Sources, see snapshot 7.4

Water Soluble Vitamins
* 8 B vitamins – Tender Romance Never Fails with 6 to 12 Beautiful Pearls (Thiamin, Riboflavin, Niacin, Folate, B6, B12, Biotin, and Pantothenic acid)
o Aid in metabolism of and energy release from carbohydrates, lipids, amino acids.
o Mode of action – coenzymes or parts of coenzymes that are necessary for the proper activity of enzymes, Without the coenzyme, compounds A and B don’t respond to the enzyme.

With the coenzyme in place, compounds A and B are attracted to the active site on the enzyme, and they react.
The reaction is completed with the formation of a new product. In this case, the product is AB.
Muscles and other tissues metabolize protein.
Brain and other tissues metabolize carbohydrates.
Bone tissues make new blood cells.
Liver and other tissues metabolize fat.
Digestive tract lining replaces its cells.

* Thiamin and Riboflavin
o Roles – energy metabolism in cells, part of nerve cell membranes.
o Deficiencies
+ Beri beri, edema &/or muscle weakness
+ Alcohol abuse – Wernicke-Korsakoff syndrome
o DRI thiamin:1.1(women) – 1.2(men) mg/day; riboflavin 1.1(women) – 1.3(men) mg/day
o Sources: All food groups except fats and oils
* Niacin – can be produced from the amino acid tryptophan.
o Roles: energy metabolism
o Deficiencies: Pellagra – dermatitis, diarrhea, dementia, death
o Toxicities (2 - 3X DRI): *prevents blood clotting, causes liver damage, enhances action of Coumadin
* Niacin
o DRI 14(women) -16(men) mg/day
o Sources, snapshot 7.8
+ Meats
+ Some vegetables and grains
* Folate
o Role: required for synthesis of DNA - ***pregnancy
o Deficiencies (drug interactions, smoking)
+ Anemia
+ Decreased immunity
+ Decreased digestive and cardiovascular function
+ Colon and cervical cancers
+ *Neural tube defects, ?other birth defects
o Toxicities (>1000 mg/day): rare, interferes with anticancer drugs.
o DRI 400 milligrams/day
o Sources, snapshot 7.8

* Vitamin B12 (requires intrinsic factor for absorption)
o Roles: works with folate, part of insulating sheath around nerves.
o Deficiencies:
+ Pernicious anemia
+ Paralysis
+ Nerve damage in fetus
o DRI 2.3 micrograms/day
o Sources, see snapshot 7.9
+ Meat and dairy
+ Implications for vegans??
* Vitamin B6
o Roles:
+ Conversion of amino acids to other amino acids
# Ex.: Tryptophan to niacin
+ Synthesis of hemoglobin and neurotransmitters
+ Release of glucose from glycogen
+ Immune function
+ Promotes steroid hormone activity
+ Development of nervous system
o Deficiencies
+ Anemia
+ Dermatitis
+ Muscle weakness
+ Behavioral problems
+ ?Heart disease
o Toxicities (>100 mg/day) – muscle weakness, nerve damage
o DRI 1.3 milligrams/day
o Sources, see snapshot 7.10
+ Meat and dairy
+ Vegetables and fruits
* Biotin and Pantothenic acid
o Roles:
+ Metabolism of carbohydrates, fats and proteins
+ Synthesis of lipids, neurotransmitters, steroid hormones, hemoglobin.
* “Non-B vitamins”: choline, carnitine, inositol, lipoic acid, etc. No beneficial effects proven!!

* Vitamin C, ascorbic acid – history of controversy
o Roles:
+ Connective tissue development, collagen
+ Antioxidant
+ Promotes iron absorption, immunity?
+ Protects vitamin E

o Deficiency – Scurvy (skin and mucous membrane damage), anemia.
o Toxicity (> 2grams/day) – pro-oxidant, activates oxidizing agents.
o DRI – 75(w) – (90(m) milligrams/day. Increased for smokers.
o Sources, see snapshot 7.11
o Notes: can interfere with diagnostic tests for diabetes, and blood clotting
o ??Prevents colds

Vitamin/Mineral Supplements

* Who needs them?
* Who does not need them?
* Oyo read - Controversy

Vitamins.ppt

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Coagulation Testing

Coagulation Testing
By:Diane Jette
BioMedica Diagnostics Inc.

Composition of Blood
* Formed Elements
o Erythrocytes (RBC)
o Leukocytes (WBC)
+ Neutrophils
+ Eosinophils
+ Basophils
+ Lymphocytes
+ Monocytes
o Thrombocytes (Platelets)
* Plasma
o 92% water
o 7 to 9 % of solutes are proteins
+ 55 to 60% Albumin, 15% Globulins, 4% Fibrinogen
o Non-protein nitrogen substance, Enzymes, Antibodies, Electrolytes, etc.
o Serum: No fibrinogen or Factors II, V and VIII

Hemostasis is the arrest of bleeding from an injured blood vessel
* Vasoconstriction and compression of injured vessels
* Platelets adhere to the site of injury and form a platelet plug
* Platelets release factors to augment vasoconstriction and initial vessel wall repair
* Platelets provide surface membrane sites and components for the formation of enzyme/cofactor complexes in blood coagulation reactions

Coagulation Reactions Lead to the Formation of a Blood Clot
* Two pathways: Intrinsic and Extrinsic - Coagulation Cascade
* Formation of a prothrombin activator - complex of Factor Xa, Factor Va and procoagulant phospholipid on surface of platelets.
* Prothrombin activator cleaves prothrombin into two fragments to give Thrombin.
* Thrombin cleaves small peptides from fibrinogen to form fibrin monomers that polymerize.
* Thrombin activates Factor XIII to cross-link the fibrin to form an insoluble clot.

Coagulation Cascade
* Intrinsic Pathway: (APTT)
o Factors VIII, IX, XI, and XII.
o Activated on surface of exposed endothelium.
o Complexes form on platelet phospholipids.
* Extrinsic Pathway: (PT)
o Factors IV, V, VII, X
o Activated by Tissue phospholipids (Tissue Factor or Tissue thromboplastin) released into blood as a result of tissue damage.
* Common Pathway (Thrombin Time)
o Factors I and II
o Leads to the formation of Fibrin Clot
o Thrombin time does not measure deficiencies in Intrinsic or Extrinsic pathway

The Role of Calcium
* Ca ions are needed for most of the reactions in the Coagulation Cascade
* Ca-chelating agents are used in vitro as anticoagulants (Citrate, EDTA, Oxalate)
* When Coagulation Factors are synthesized without Vitamin K they cannot bind Ca and lose enzymatic function

Regulatory Mechanisms
* Inhibition of Factor Activity
o Plasma protease inhibitors: anti-thrombin III (ATIII), *2-macroglobulin, *1 - antiprotease
o Heparin converts ATIII from a slow acting inhibitor to an instantaneous inhibitor of Thrombin, Factor Xa and Factor IXa
o Protein C and Protein S are serine proteases that cleave Factors VIII and Factor Va rendering them inactive

Fibrolysis
* Fibrin clot is degraded by protolytic enzymes and fragments dissolved in blood
* Process is catalyzed by Plasmin
* Plasminogen is converted to Plasmin
* Activation by tissue plasminogen activator (tPA) and urokinase
* Fibron degrades into large fragments X and Y then smaller fragments D and E

Regulation of Fibrolysis
* Plasminogen activator inhibitors (PAIs) and plasmin inhibitors slow the fibrolysis process
* tPA and urokinase have short half-lives and are rapidly cleared through the liver
* Unbound plasmin is instantaneously neutralized by 2-antiplasmin

Hereditary Coagulation Disorders
* Hemophilia A
o Factor VIII deficiency
o 80% of all Hemophilia cases
* Hemophilia B
o Factor IX deficiency
* Prolonged ATPP
o Recovered by dilution 1:1 with normal plasma
* Normal PT and Normal Bleeding Time
* Factor XI Deficiency
o 5 to 9% of European Jews
* 2-antiplasmin Deficiency

Acquired Coagulation Disorders
* Liver Disease
o Impaired clotting Factor synthesis
o Increased fibronolysis
o Thrombocytopenia
* Desseminated Intravascular Coagulation (DIC)
o Something enters the blood that activates factors
o Complication of obstetrics, infection, malignancy, shock, severe brain trauma
o Elevated PT, APTT, D-Dimer and other fibron degradation products

Circulating Anticoagulants
* Antibodies that neutralize clotting factor activity
* Factor VIII Anticoagulants
o Antibody
o Same profile as Hemophilia A
o Clotting time not restored by mixing with normal plasma
o Life-threatening condition

Lupus Anticoagulants
* Antibodies to phospholipid binding sites on clotting factors
* Prevent factors from accumulating on phospholipid surfaces
* Elevated APTT clotting times not corrected with mixing with normal plasma
* PT normal or slightly elevated.
* Non-specific depression of clotting factor activities (Factors VIII, IX, XI, XII)
* Test sensitivity increased by using diluted reagent
o Dilute ATPP reagent, Russell’s viper venom time, Kaolin time
o Clotting times corrected with the addition of phospholipids

Oral Anticoagulant Therapy
* Coumadin or Warfarin
* Inhibitor of Vitamin K dependant Factor synthesis
* Oral anticoagulant
* Dose regulated by therapeutic effect
* PT assay to measure INR
* INR range established for optimum therapeutic effect (typically 2.0 to 3.0)

Prothrombin Time: PT
* PT reagent contains Calcium ions and Thromboplastin from brain tissue (Rabbit).
* Thromboplastin (Tissue Factor) protein-lipid complex found in tissues outside blood vessels.
* Measures the function of the Extrinsic Pathway.
* Sensitive to Factors IV, V, VII, X.
* Provided as a lyophilized reagent.
* Used to monitor oral anticoagulant therapy (Warfarin / Coumadin).

PT Reagent Calibration
* Reagents are calibrated against standard PT reagent established by the WHO.
* ISI = International Sensitivity Index.
* ISI is assigned by the manufacturer for each lot of reagent using reference material traceable to WHO.
* The lower the ISI the more sensitive the Reagent
o ISI of 1.8 to 2.4 = Low sensitivity (North American Standard PT)
o ISI of 1.4 to 1.8 = Average sensitivity
o ISI 1.0 to 1.4 = High Sensitivity

PT: INR Values
* INR = International Normalised Ratio.
* MNP = Mean Normal Plasma.
* INR = (PT / MNP)ISI
* An INR of 1.0 means that the patient PT is normal.
* An INR greater then 1.0 means the clotting time is elevated.

INR Calculation
* Example 1
o MNP = 12.0 s
o ISI = 1.25
o Patient Plasma = 20 s
o INR = (20.0 / 12.0)1.25 = 1.9
* Example 2
o MNP = 12.0 s
o ISI = 1.85
o Patient Plasma = 17 s
o INR = (17.0 / 12.0)1.85 = 1.9
* Example 3
o MNP = 12.0 s
o ISI = 1.4
o Patient Plasma = 20 s
o INR = (20.0 / 12.0)1.4 = 2.0
* Example 4
o MNP = 12.0 s
o ISI = 2.0
o Patient Plasma = 20 s
o INR = (20.0 / 12.0)2.0 = 2.8

Expected PT Values
* Mean Normal Plasma = 10 to 14 seconds.
* Mean Normal Plasma value varies with PT sensitivity. A high sensitivity (Low ISI) PT will give a high normal PT value (13 to 15 seconds).
* Oral anticoagulant monitoring = Target INR of 2.0 to 3.0.
* INR of greater than 5 or 5.5 = unacceptable high risk of bleeding.
* %CV between duplicates less than 5%

Performing a PT test
* Pre-warm PT reagent and sample to 37 oC
* Add 100 L sample to cuvette
* Add 200 L of PT reagent to cuvette
* Start timer
* Record time to clot in seconds
* Calculate INR
* see product insert for PT

Activated Partial Thromboplastin Time
* APTT or PTT
* Reagent contains phospholipids and a ‘surface activator’; (Ellagic Acid, Micronized Silica)
* Calcium Chloride reagent added to start the reaction.
* APTT reagent mimics the surface of a platelet.
* Measures activity of clotting factors in the Intrinsic Pathway, factors VIII, IX, XI and XII
* No WHO calibration standard

Uses of APTT
* Sensitive to 30 to 40% deficiencies of all factors except VII and XIII.
* Heparin inhibits the activity of clotting factors in the Intrinsic Pathway.
* A standard curve (APTT time vs Heparin concentration) is prepared using a heparin standard.
* APTT is also sensitive to other non-specific Factor inhibitors such as Lupis Anticoagulant.
* Can be influenced by Vitamin K deficiency and Coumadin therapy.
* Negative APTT result usually rules out Hemophilia.

Expected APTT Values
* Normal Range: 26 to 40 seconds
* Slightly Elevated: 45 to 65 seconds
* Extremely Elevated = > 70 seconds
* %CV less than 7%

Performing an APTT Test
* Pre-warm Calcium Chloride reagent to 37 oC.
* Add 100 microL of sample to cuvette.
* Add 100 microL of APTT to cuvette and incubate for 3 minutes.
* Add 100 microL of Calcium Chloride reagent and start timer.
* Record the time to clot in seconds.
* See APTT product Insert

Heparin Monitoring
* Prepare Heparin Standards
o Prepare stock heparin (10 USP units/mL)
o Prepare working heparin dilutions (0.1 to 0.8 U/mL) by diluting stock in normal plasma
o Run heparin dilutions as samples in APTT assay
* Plot the results as U/mL vs Log Clotting times
* Run patient samples in APTT assay and determine heparin concentration from the plot.

Heparin Calibration Curve
Factor Substitution Tests:
PT and APTT
* Dilute patient sample one to one with adsorbed plasma and serum to determine if normal clotting time is restored.
* Serum: Source of Factors IX, X, XI & XII
* Adsorbed Plasma: Source of Factors VIII, V, XI, & XII

Factor Plots: PT and APTT
* Dilute a normal plasma sample or control 1 to 10 in saline
* Dilute in saline: 100%, 50%, 25%, 12.5%. 6.25%, 3.12%,
* Mix one to one with a factor deficient plasma.
* Measure PT or APTT and plot Log % Factor vs Log clotting time.
* Dilute patient plasma 1 to 10 in saline.
* Mix one to one with a factor deficient plasma.
* All factors will be restored except the deficient factor. If the factor is present in test sample no reduction in clotting will be seen. (Same clotting time as the 100% standard)
* Determine percent factor from standard curve.

Factor Calibration Curve
Plasma Controls
* Used to monitor assay performance (QC)
* Made from pooled normal human plasma with some factors selectively adsorbed.
* Three levels available:
o Level 1 control represents a normal plasma
o Level 2 represents a slightly elevated plasma (INR ~ 1.5)
o Level 3 represents a severely elevated plasma (INR ~ 2.5)
* Each laboratory should establish expected ranges for PT and APTT.

Thrombin Time (TT or TAT)
* Measures common pathway.
* Fibrinogen --> Fibron Clot
* Not sensitive to deficiencies in Intrinsic or Extrinsic pathways.
* Reagent consists of animal thrombin.
* Normal Clotting time is 15 seconds.
* If elevated sample is mixed one to one with normal and re-tested. If normal clotting is not restored then an anti-coagulant is present.
Bleed Time Test
* An incision is made
* Time to stop bleeding is measured
* Normal clotting time is 7.5 minutes

D-Dimer Test
* D-Dimer is a fibrin monomer
* Product of fibrolysis
* Latex agglutination assay is used
* Anti-D-Dimer antibody coated on micro-latex beads
* Cardiac Infarction Marker

Activated Clotting Time (ACT)
* Clotting time of whole blood in the presence of silica based activator.
* Normal clotting times = 90 to 170 sec.
* Used to monitor heparin doses from 1 to 10 U/mL (APTT is sensitive to heparin at 0.2 to 1 U/mL).
* Used with invasive procedures that require on-site adjustment of heparin and protamine dosage. (ex. Cardiopulmonary bypass surgery).
* Not amenable for use with an optical instrument, too cloudy.
* Also called HMT, Heparin Management Test

Fibrin-1 Clot Detection
LIGHT SOURCE
CUVETTE
DETECTOR
Clot Detection
Time in seconds
Optical Density
Change in slope > Threshold = CLOT

Coagulation Testing.ppt

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