Examination of Urine

Examination of Urine
By:Terry Kotrla, MS, MT(ASCP)
Professor
Austin Community College


Urine Color

* Normal urine color ranges from pale yellow to deep amber — the result of a pigment called urochrome
o B vitamins turn urine an eye-popping neon yellow BUT may also indicate liver disease.
o porphyria, a disease that affects your skin and nervous system, turns urine the color of port wine.

Urine Color

* Most changes in urine color are harmless and temporary and may be due to:
o Certain foods – beets may turn urine red
o Dyes in foods/drinks
o Supplements – vitamins
o Prescription drugs
* Unusual urine color can indicate an infection or serious illness .

Suggested Colors

* pale yellow (straw)
* light yellow
* yellow
* green-yellow (olive)
* red-yellow
* red
* red-brown
* brown-black
* black
* milky

Examples of Urine Color

Urine Clarity

* During the visual inspection, the MLT observes the urine's and determines how clear it is (its clarity).
* Urine clarity refers to how clear the urine is.
* Terms used: clear, slightly cloudy, cloudy, or turbid.
* “Normal” urine can be clear or cloudy.
* The clarity of the urine is not as important as the substance that is causing the urine to be cloudy.

Urine Clarity

* Substances that cause cloudiness but that are not considered unhealthy include:
o mucous,
o sperm and prostatic fluid,
o cells from the skin,
o normal urine crystals, and
o contaminants (like body lotions and powders).
* Other substances that can make urine cloudy (such as red blood cells, white blood cells, or bacteria) indicate a condition that requires attention.

Examples of Urine Clarity

Urine Color and Clarity

* Urine color and clarity can indicate what substances may be present in urine.
* Confirmation of suspected substances is obtained during the chemical and microsopic examination.

Chemical Examination

* Reagent strips are used only once and discarded.
* Testing
o Perform within 1 hour after collection
o Allow refrigerated specimens to return to room temperature.
o Dip strip in fresh urine and compare color of pads to the color chart after appropriate time period.
o Instruments are available which detect color changes electronically

Using Reagent Strips

* BRIEFLY dip the strip in urine.
* Colors are matched to those on the bottle label at the appropriate times.
* Timing is critical for accurate results.

Reagent Strips

Glucose

* Presence of glucose (glycosuria) indicates that the blood glucose level has exceeded the renal threshold.
* Useful to screen for diabetes.

Bilirubin

* Bilirubin is a byproduct of the breakdown of hemoglobin.
* Normally contains no bilirubin.
* Presence may be an indication of liver disease, bile duct obstruction or hepatitis.
* Since the bilirubin in samples is sensitive to light, exposure of the urine samples to light for a long period of time may result in a false negative test result.

Ketones

* Ketones are excreted when the body metabolizes fats incompletely (ketonuria)

Specific Gravity

* Specific gravity reflects kidney's ability to concentrate.
* Want concentrated urine for accurate testing, best is first morning sample.
* Low – specimen not concentrated, kidney disease.
* High – first morning, certain drugs

Blood

* Presence of blood may indicate infection, trauma to the urinary tract or bleeding in the kidneys.
* False positive readings most often due to contamination with menstrual blood.

Ph

* pH measures degree of acidity or alkalinity of urine

Protein

* Presence of protein (proteinuria) is an important indicator of renal disease.
* False negatives can occur in alkaline or dilute urine or when primary protein is not albumin.

Urobilinogen

* Urobilinogen is a degradation product of bilirubin formed by intestinal bacteria.
* It may be increased in hepatic disease or hemolytic disease

Nitrite

* Nitrite formed by gram negative bacteria converting urinary nitrate to nitrite

Leukocytes

* Leukocytes (white blood cells) usually indicate infection.
* Leucocyte esterase activity is due to presence of WBCs in urine while nitrites strongly suggest bacteriuria.

Normal Values

* Negative results for glucose, ketones, bilirubin, nitrites, leukocyte esterase and blood.
* Protein negative or trace.
* pH 5.5-8.0
* Urobilinogen 0.2-1.0 Ehrlich units

Handling and Storage of Strips

* Handling and Storage
o Keep strips in original container
o Do not touch reagent pad areas
o Reagents and strips must be stored properly to retain activity
+ Protect from moisture and volatile fumes
+ Stored at room temperature
o Use before expiration date

Procedure

* Dip strip briefly, but completely into well mixed, room temperature urine sample.
* Withdraw strip.
* Blot briefly on its side.
* Keep the strip flat, read results at the appropriate times by comparing the color to the appropriate color on the chart provided.

Sources of Error

* Timing - Failure to observe color changes at appropriate time intervals may cause inaccurate results.
* Lighting - Observe color changes and color charts under good lighting.
* QC - Reagent strips should be tested with positive controls on each day of use to ensure proper reactivity.
* Sample - Proper collection and storage of urine is necessary to insure preservation of chemical.

Sources of Error

* Testing cold specimens - would result in a slowing down of reactions; test specimens when fresh or bring them to RT before testing
* Inadequate mixing of specimen - could result in false reduced or negative reactions to blood and leukocyte tests; mix specimens well before dipping
* Over-dipping of reagent strip - will result in leaching of reagents out of pads; briefly, but completely dip the reagent strip into the urine

Examination of Urine

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Blood Collection

Blood Collection

An overview of the process involved in collecting donor blood

Donor Screening
* Starts with the donor and first impressions are critical
* Clean, well lit donation facility from waiting room to collection area
* Pleasant, professional staff who can ask the appropriate questions, observe and interpret the responses, and ensure that the collection process is as pleasant as possible

Blood Bank versus Blood Center
* Confusion exists and terms are sometimes used inappropriately
* Blood bank in a hospital is also known as the transfusion service, performs compatibility testing and prepares components for transfusion
* Blood Center is the donation center, screens donors, draws donors, performs testing on the donor blood, and delivers appropriate components to the hospital blood bank

Standards, Regulations, Governing Bodies
* Strict guidelines exist and inspections are performed in both blood centers and blood banks to ensure the safety of the donors and patients
* Some or all of the following agencies may be involved:
o AABB – American Association of Blood Banks
o FDA – Food and Drug Administration
o CAP – College of the American Pathologists
o JCAHO - Joint Commission on the Accreditation of Hospital Organizations
o NCCLS – National Committee for Clinical Laboratory Standards

Donor Screening
* Medical History based on a standardized questionnaire obtains critical information about the donor’s health and risk factors which may make it unsafe for donation
* Physical Exam which includes blood pressure, temperature, pulse and screen for anemia are performed to ensure donor is healthy enough to donate.
* Two goals of screening
o Protect the health of the potential donor
o Protect the health of the potential recipient

Donor Registration
* Donor signs in
* Written materials are given to the donor which explains high risk activities which may make the donor ineligible
* Donor must be informed and give consent that blood will be used for others unless they are in a special donor category
* First time donors must provide proof of identification such as SS#, DL#, DOB, address and any other unique information.
* Repeat donors may be required to show DL or some other photo ID

Frequency of donation
* Whole blood or red blood cells 8 weeks
* Plateletpheresis – up to 24 times/year
* Plasmapheresis– once every 4 weeks, can be done twice a week
* Granulocytes

Medical History
* A thorough history is obtained each time
* Standardized universal questionnaire is used
* Questions are asked that are very intimate in nature but are critical in assessing HIV or HBV risks
* Medications the donor taking are present in plasma, may cause deferral
* Infections the donor has may be passed to recipient, may be cause for deferral

12 Month Deferral
* Any intimate sexual relations with HIV positive, HBV positive, hemophiliacs, drug users or individuals receiving drugs/money for sex.
* Recipient of blood, components or blood products such as coagulation factors
* Sexually transmitted disease-if acquired indicates safe sex not practiced and donor at risk for HIV and HBV
* Travel to malarial endemic country

Temporary Deferrals
* Certain immunizations
o 2 weeks -MMR, yellow fever, oral polio, typhoid
o 4 weeks -Rubella, Chicken Pox
o 2 months – small pox
* Pregnancy – 6 weeks upon conclusion
* Certain medications
o Proscar/Propecia, Accutain – 1 month
o Avodart – 6 months
o Soriatane – 3 years
o Tegison - permanent

Permanent Deferrals
* HIV, HBV, or HCV positive
* Protozoan diseases such as Chagas disease or Babesiosis
* Received human pituitary growth hormone
* Donated only unit of blood in which a recipient contracted HIV or HBV
* Was the only common donor in 2 cases of post-transfusion HIV or HBV in recipient
* Lived in a country where Creutzfeld-Jacob disease is prevalent
* Most cancers except minor skin cancer and carcinoma in-situ of the cervix
* Severe heart disease, liver disease

Helpful Hint
* Permanent deferral – any member of high risk group such as: HIV/HBV/HCV pos, drugs/sex for money, cancer, serious illness or disease, CJD, Chagas disease, Babesiosis
* 12 month deferral – sex with any high risk group, any blood exposure, recipient of blood/blood products, STD, jail/prison, rabies vaccine after exposure, HBIG, malaria
* Have to memorize: medications and vaccinations

Self-Exclusion
* Two stickers
o “Yes, use my blood”
o “No, do not use my blood”
* After interview the donor will place the appropriate bar coded label on the donation record
* If “no” selected the unit is collected, fully tested, but not used for transfusion
* Allows donors who know they are at risk to “save face” if pressured to donate by friends and family

Donor Categories
* “Allogeneic”, “homologous” and “random donor” terms used for blood donated by individuals for anyone’s use
* Autologous – donate blood for your own use only
* Recipient Specific Directed donation – donor called in because blood/blood product is needed for a specific patient
* Directed Donor – patient selects their own donors
* Therapeutic bleeding – blood removed for medical purposes such as in polycythemia vera. NOT used for transfusion.

Auto/Directed Blood Labels
Donor Categories
* Safest is autologous, blood is your own, no risk of disease acquisition
* Most dangerous is Directed Donor, you select a donor who may, unknown to you, be in a high risk category but feels obligated to follow through and donate

Blood Collection
* Materials used are sterile and single use.
* Most important step is preparing the site to a state of almost surgical cleanliness.
* Bacteria on skin, if present, may grow well in stored donor blood and cause a fatal sepsis in recipient
* Use 16-17 gauge needle to collect blood from a single venipuncture within 15 minutes
* Collect 450 +/- 45 mLs of blood

Donor Reactions
* Syncope (fainting)
o Remove needle immediately
* Hyperventilation
o Have donor rebreathe into paper bag.
* Nausea/vomiting
* Twitching/muscle spasms
* Hematoma
* Convulsions – rare, get immediate assistance
* Cardiac difficulties

Post-Phlebotomy Care
* Donor applies pressure for 5 minutes
* Check and bandage site
* Have donor sit up for few minutes
* Have donor report to refreshment area for additional 15 minutes of monitoring

Post-Phlebotomy Instructions
* Eat/drink before leaving
* Wait until staff releases you
* Drink more fluids next 4 hours
* No alcohol until after eating
* Refrain from smoking for 1 hour
* If bleeding continues apply pressure and raise arm
* Faint or dizzy sit with head between knees
* Abnormal symptoms persist contact blood center.
* Remove bandage

Testing Donor Blood
* CANNOT rely on previous testing
* Records must be kept for 5 years

Serological Testing
* ABO/D typing
* Antibody Screen – if positive, ID antibody, cannot make plasma products
* Antibodies to other blood group antigens which are present in the donor may react with recipient red cells resulting in a reaction.

Disease Testing
* Disease testing include:
o HBsAG
o HBc
o HCV
o HIV 1&2
o HTLV I/II
o RPR
o NAT for HIV-1, HCV & WNV

Results of Testing
* Tests for disease markers must be negative or within normal limits.
* Donor blood which falls outside these parameters must be quarrantined.
* Repeat testing, if still abnormal must dispose.

Transfusion Service Testing
* The only repeat testing required is:
o ABO on red cell products
o D typing (IS) on D negative red cell products
* Plasma products (FFP, CRYO, PLTS) do not require any testing.
* Donor samples must be stored at 1-6C for at least 7 days after transfusion
o ADSOL unit transfused today must save sprig for one week
o Many facilities will pull a sprig from each donor during processing and save all sprigs for 49 days, regardless of expiration of unit

Summary
* Blood collection starts with screening of the donor to:
o Ensure they are healthy enough to donate
o Ensure they do not have transmissible diseases
* Many organizations set standards and monitor all aspects of blood collection and administration.
* Collection of blood must be done in such a manner as to ensure sterility of the component.
* Testing of donor blood includes serological testing for ABO/D typing, antibody screening, and testing for markers indicating infection.
* The blood supply is NOT safe, only careful screening and testing can prevent, as much as possible, disease transmission.

Blood Collection

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Assessment of Protein Status

Assessment of Protein Status
FCSN 442 - Nutrition Assessment Laboratory
By:Dr. David L. Gee
Central Washington University

Assessment of Protein Status
* Anthropometric Assessment
o body composition estimations
o midarm muscle circumference/area
* Laboratory Assessment
o serum albumin
o other serum proteins (transferrin, prealbumin, retinol-binding protein)
o urinary creatinine excretion
o total lymphocyte count

Midarm Muscle Area
* Estimate of MAMA is an estimate of overall muscle mass
* Assumptions

Midarm Muscle Circumference
* MAMC = AC - (.314 x TSF)

* “…change in arm muscle area is greater than the change in mid-arm circumference. Consequently, changes in upper-arm musculature are not as easily detected by measurement of mid-arm circumference as by AMA. Therefore, AMA is the preferred nutritional index.”

Arm Muscle Area
* AMA = ((MAC - (3.14 x TSF)2 ) / (4 x 3.14)
* adjusted AMA

Guidelines for Interpreting Percentile Values for Arm Muscle Area (appendix R)
Biochemical Assessment of Protein Status
* Two protein compartment model
* “No single test or group of tests can be recommended at this time as a routine and reliable indicator of protein status.” Young, 1990
* “…a combination of measures can produce a more complete picture of protein status.”

Serum Albumin
* Major serum protein
* Most common indicator of depleted protein status
* Half life = 14-20 days
* poor indicator of early protein depletion and repletion
* Levels affected by rate of synthesis (liver disease may reduce levels)
* May reflect level of physiological stress
* Levels affected by abnormal losses
* Levels affected by fluid status
* Normal values: 4.5 g/dL + 35-50 (SD)

Serum Transferrin
* Function: transport protein for iron
* half-life = 8-9 days
* Influenced by other factors
* limited usefulness in protein status assess.

Serum Prealbumin
* aka. transthyretin and thyroxine-binding prealbumin
* functions:
* short half life (2-3d), small body pool
* Returns to normal at beginning of nutritional therapy
* Influenced by other factors
* generally considered preferable than albumin and transferrin

Retinol Binding Protein
* Function: carrier for retinol
* responds like prealbumin
* very rapid turnover (12 hours), very small body pool
* generally not considered to be more useful than prealbumin

Immunocompetence
* Immune system affected by nutritional status
* Tests of immunocompetence useful functional indicators of nutritional status
* Delayed Cutaneous Hypersensitivty (DCH)
o intradermal injection of antigens
* Total Lymphocyte Count (TLC)

Total Lympocyte Count
* White blood cell count
* TLC = (%lymp x WBC)x100
* Normal = 1200-1800 cells/mm3
* Moderate PCM = 800-1200
* Severe PCM = < 800 Urinary Creatinine Excretion * Creatinine excreted in proportion to muscle mass * LBM estimated by comparing 24-hr urine creatinine excretion with standard based on stature or reference values of 23 and 18 mg/kg for M and F Example: Creatinine Height Index * CHI = (24 hr urine creatinine x 100) / (expected 24 hr urine creatinine for height) o CHI = 1436/1596 x 100 = 90% * expected values in table 9-1 (p306) o CHI > 80% = normal
o CHI = 60-80% = mild protein depletion
o CHI = 40-60% = moderate depletion
o CHI < 40% = severe depletion Assessment of Protein Status

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