03 October 2009

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

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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

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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

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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

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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

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30 September 2009

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.

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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

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Immunoassays



Immunoassays
By:Diane C. Jette, Ph.D.
BioMedica Diagnostics Inc.

Test Menu
* Infectious Diseases
* Cardiac Markers
* Cancer Screening
* Fertility / Hormones
* Drugs of Abuse
* Other Tests
o IgE
o Rh Factor
o Occult Blood
o TSH, T3, T4
o Blood Grouping

Test Formats Available
* Latex Agglutination
* DIPSTICK
* Card Format
* Cartridge Format
* ELISA Format with Plate Reader

Structure of IgG
(150,000 Daltons)
Antigen
Binding Site
Fab
Fc

Structure of IgM
(900,000 Daltons)
Binding Sites
Sandwich ELISA Procedure
* Antibody coated on plate.
* Incubate with sample containing antigen.
* Wash away unbound material.
* Incubate with antibody-enzyme conjugate.
* Wash away unbound conjugate.
* Add substrate.
* Enzyme acts on substrate and produces color change.
* Measure amount of color produced.
* Amount of antigen present is proportional to the amount of color produced.

ELISA: Sandwich Format
Sandwich Assay Results
Color Intensity (OD)
Antigen Concentration
Linear Range
ELISA: Inhibition Assay Procedure

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Urine Analysis



Urine Analysis
By:Diane C. Jette, Ph.D.
BioMedica Diagnostics Inc.


Reagent Test Strips
* Multiple test reagents on a ready to use test strip.
* Test results are read at different times after brief exposure to urine sample.
* The color on strip is compared to the reference color shown on test strip packaging.

Typical Test Strip Test
Glucose
Bilirubin
Ketone
Blood
Protein
Nitrite
Leukocytes
pH
Specific Gravity
Urobilinogen
Sensitivity_
* 4 to 7 mmol/L
* 7 to 14 mol/L
* 0.5 to 1.0 mmol/L (Acetoacetic acid)
* 150 to 620 g/L (Hemoglobin)
* 0.15 to 0.3 g/L (Albumin)
* 13 to 22 mol/L
* 5 to 15 cells/ L
* pH 5.0 to 8.5
* 1.000 to1.030
* 0.2 to 8 mol/L

Glucose
* Small amounts of glucose normally excreted by the kidney.
* Below sensitivity of the test.
* >6 mmol/L clinically significant.

Bilirubin

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29 September 2009

Andrews’ Diseases of the Skin



Andrews’ Diseases of the Skin
By:Boris Ioffe, D.O.

Recalcitrant Palmoplantar Eruptions

* Recalcitrant pustular eruptions of the hands and feet are often examples of psoriasis
* Need to then search for lesions elsewhere on the body(e.g., scalp, ears, glans penis)
* Search also for a family history to confirm your suspicion

Dermatitis Repens
* Aka- acrodermatitis continua and acrodermatits perstans
* It’s a chronic inflammatory disease of hands and feet
* Rarely, can become generalized
* Usually, as a pustule or paronychia
* Occasionally, mucous membranes are involved
* Nails are often dystrophic or destroyed
* Lesions cause skin atrophy
* Crusted, eczematoid, and psoriasiform lesions may occur, and there may be moderate itching
* It is essentially unilateral in its beginning and asymmetrical throughout its entire course
* Histology
o similar to those seen in psoriasis
o the primary lesion is epidermal
o An intraepithelial spongiform pustule is formed by infiltration of pmn’s
* Treatment
o topical mechlorethamine, topical steroids, PUVA, fluorouracil, and sulfapyridine
o Acitretin, low dose cyclosporine, Acitretin plus calcipotriol

Palmoplantar Pustulosis
* AKA pustular psoriasis
* In contrast to dermatitis repens it is essentially bilateral and symmetrical
* Locations include: thenar/hypothenar eminences or central portion of the palms and soles
* Patches begin as erythematous areas in which pustules form
* Start as pinhead-sized, enlarge and coalesce to form small lakes of pus
* In the course of a week, they tend to dry up, leaving punctate brown scabs that eventually exfoliate
* Stages of quiescence and exacerbation characterize the condition
* Meds, such as lithium, have been reported to induce
* Nails may become malformed, ridged, stippled, pitted and discolored
* May be associated with psoriasis vulgaris
* Some regard palmoplantar pustulosis as a form of psoriasis, while others consider it a separate entity
* Female predominance; lack of seasonal variation; different histopathologic features and
* Associated with thyroid disorders and cigarette smoking
* May be predisposed to joint disease and possibly SAPHO syndrome-Synovitis, Acne, Pustulosis, Hyperostosis and Osteoarthritis
* It’s resistant to most treatments
* Acitretin is reportedly effective(1mg/kg/day)
* Low-dose cyclosporine (1.25mg/kg/day-3.75mg/kg/day)
* Intramuscular Kenalog (40-60mg)may be effective for short-term relief

Pustular Bacterid
* Characterized by a symmetric, grouped, vesicular or pustular eruption on palms and soles
* Marked by exacerbations and remissions over long periods
* No involvement of webs of fingers or toes or flexion creases of toes
* WBC may be elevated
* Scaling is usually present
* Etiology is thought to be a remote focus of infection; infection needs to be treated before resolution will occur

Juvenile Plantar Dermatosis
* Usually begins as a patchy, symmetrical, smooth, red, glazed macule on great toes, sometimes with fissuring and desquamation in children aged 3-13
* Toe webs are rarely involved; fingers may be
* Histologically, there is psoriasiform acanthosis and a sparse, lymphocytic infiltrate in the upper dermis
* Spongiosis is commonly present
* Tx: bed rest, cotton socks and topical steroids
* Spontaneous resolution within 4 yrs is the rule

Infantile Acropustulosis
* Intensely itchy vesicopustular eruption of hands and feet
* Begins at any age up to 10 months, clearing in a few weeks and recurring repeatedly until final resolution at 6 – 36 months of age
* Dapsone at 2mg/kg/day may help
* Potent topical steroids aid in symptomatic relief
* Should prompt an extensive workup to eliminate serious infectious causes (i.e., Tzanck prep, gram stain, KOH prep of pustule)
* Some suspect that this condition may be a persistent reaction to prior scabies

Infantile Acropustulosis
* Acropustulosis of infancy
Pompholyx
* AKA dyshidrosis
* A vesicular eruption of palms and soles characterized by spongiotic intraepidermal vesicles and often accompanied by burning or itching
* Hyperhidrosis may be present
* Usually bilateral and symmetrical
* Bullae may form
* Contents are clear and colorless
* Attacks generally last a few weeks
* Lesions dry-up and desquamate rather than rupture
* Etiology- stress, atopy, and topical as well as ingested contactants
* Histopathology: spongiotic vesicles in the epidermis
* Differential dx:
o dermatophytid, contact dermatitis, atopic dermatitis, drug eruption, pustular psoriasis of palms and soles, acrodermatitis continua, and pustular bacterid
* Rarely, T-cell lymphoma can present with similar clinical findings, but biopsy of the vesicles will be diagnostic
* Tx: high potency corticosteroid creams
* Triamcinolone acetonide intramuscularly or a short course of oral prednisone is rapidly effective
* Oral or topical psoralen + UVA (PUVA) is effective but costly & inconvenient
* In more severe forms, immunosuppressive mycophenolate mofetil has been effective

Lamellar Dyshidrosis
* AKA dyshidrosis lamellosa, keratolysis exfoliativa
* A superficial exfoliative dermatosis of the palms and sometimes soles
* Referred to as recurrent palmar peeling
* Involvement is bilateral
* Can occur in association with dyshidrosis
* Often exacerbated by environmental factors
* Differential dx: dermatophytosis, chronic contact dermatitis
* Tx: difficult
* Spontaneous involution can occur in a few weeks for some
* Most tends to be chronic and relapsing
* Tar creams (Zetone cream) usually helps
* 5% tar in gel (Estar Gel) is an excellent tx
* Lac-Hydrin lotion and Carmol 10 or 20 are often effective
* NB-UVB may be helpful

Palmoplantar Keratoderma
* AKA tylosis, keratosis, hyperkeratosis
* Characterized by excessive formation of keratin on the palms and soles
* Acquired
o Keratosis Punctata of the Palmar Creases
o Punctate Keratoses of the Palms and Soles
o Porokeratosis Plantaris Discreta
o Keratoderma Climactericum
* Congenital


Punctate Keratosis of the Palms and Soles
* Primary lesion is a 1-5mm round to oval, dome-shaped papule distributed over left hand and hypothenar eminence
* Main symptom is pruritis
* Lesions number from 1 to >40
* Affects mainly blacks
* There’s a potential risk of developing lung and colon cancer

Keratosis Punctata of the Palmar Creases
* Common most often in black pts
* Primary lesion is a 1-5mm depression filled with a conical keratinous plug
* Primarily, in creases of palms or fingers, occasionally in soles
* Lesions are multiple
* Friction aggravates lesions causing them to become verrucoid or surrounded by callus
* Punctate keratoses of the palmar creases in an African-American
* PPPK-punctate palmoplantar keratoderma

Porokeratosis Plantaris Discreta
* Occurs in adults, Female:Male (4:1)
* Characterized by sharply marginated, rubbery, wide-based papule that does not bleed on removal
* Lesions are multiple, painful, 7-10mm in diameter
* Usually on wt bearing areas of sole, beneath metatarsal heads
* Tx: foot pads to redistribute wt, surgical excision, blunt dissection

Keratoderma Climactericum
* Characterized by hyperkeratosis of palms and soles beginning at about the time of menopause
* Descrete, thickened, hyperkeratotic patches most pronounced at pressure sites
* Fissuring may be present
* Tx: keratolytics -- 10% salicylic acid, lactic acid creams, etc.

Hereditary syndromes
* These have palmoplantar keratoderma as a feature
o Unna-Thost
o Papillon-Leferve
* Dominant inheritance; congenital thickening of epidermal horny layer of the palms and soles
* Usually symmetrical
* Epidermis becomes thick, yellowish, verrucous, and horny
* Striate and punctate forms occur

Unna Thost
* Occasionally nails become thickened
* 5% salicylic acid may help
* Lac Hydrin 12% may be tried
* Acitretrin or isotretinoin may be considered, but need for lifetime tx makes them impractical
* Focal palmoplantar keratosis of the striate type on the sole
* Diffuse non-epidermolytic palmoplantar keratosis
* Diffuse epidermolytic palmoplantar keratosis with diffuse hyperkeratosis

Papillon-Lefevre Syndrome
* Palmoplantar hyperkeratosis with peridontosis
* Usually develops within the first few months of life but may occur in childhood
* Well demarcated, erythematous, hyperkeratotic lesions on palms and soles
* Transverse grooves of fingernails may occur
* Early onset peridontal disease has been attributed to damage and alteration in PMN function caused by Actinomyces actinomycetemcomitans
* Disease associations include: acroosteolysis, and pyogenic liver abcesses
* There are asymptomatic ectopic calcifications in the choroid plexus and tentorium
* Therapy may retard both dental and skin abnormalities
* Treatment with Acitretin in four siblings was reported to be effective

Papillon-Lefevre Syndrome
* Papillon-Lefevre syndrome: plantar keratoderma

Mutilating Keratoderma of Vohwinkel
* Palmoplantar hyperkeratosis of the honeycomb type-associated with starfish-like keratosis on backs of hands and feet; linear keratoses of the elbows and knees, and annular constriction (pseudo-ainhum) of the digits, this may progress to autoamputation
* More than 30 cases have been reported world-wide
* More common in women and in whites
* Onset is in infancy or early childhood
* Vohwinkel’s mutilating syndrome: A.) diffuse keratoderma of palms with B.) pseudoaainhum formation

Palmoplantar Keratodermas & Malignancy
* Diffuse, waxy keratoderma of palms and soles occurring as an AD trait associated with esophageal carcinoma
* Other related factors are oral leukoplakia, esophageal srictures, squamous carcinoma of tylotic skin, carcinoma of larynx and stomach
* Acquired forms of palmoplantar keratodermas have also been associated with carcinoma of esophagus, lung, breast, bladder and stomach
* Focal PPK in association with carcinoma of the esophagus

Acrokeratoelastoidosis of Costa

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