Urnialysis: Pre-analytical Examination.

After recieving a 24 hour urine for quantitative total protein analysis, the technician must first:

The following results were obtained on a urine specimen at 8am.

pH:  5.5

protein:  2+

glucose 3+

ketones 3+

blood: negative

bilirubin: positive

nitrite: positive

If this urine was stored uncapped at 5*C without preservation and retested at 2pm. which of the following test results would be changed due to these storage conditions?

Physical examination:

A patient with uncontrolled diabetes mellitus will most likely have:

Chemical Examination:

Which of the following can give a false negative protein reading?

vitamine C

When performing a routein urinalysis, the technician notes a 2+ protein result.

He should:

Microscopic examination:

In most compound light microscopes, the ocular lens has a magnification of:

acute interstistal nephritis

acute interstistal nephritis is caused by an allergic reaction resulting in inflammation of the renal tubules. The reaction is frequently caused by a medication. As a result of the allergic reaction, eosinophils are increased. An eosinophil count can aid in confirming the diagnosis.

A patient addmitted following an accident involving massive crush injuries has the following urinalysis results:

color:  red brown                      microscopic findings

clarity: clear                               renal tubular epithelial cells 5-10

specific gravity: 1.011               renal tubular cell cast         1-2

pH: 6.0

protein: 1+

blood: large

glucose: negative

ketones: negative

nitrite: negative

leukocyte: negative

bilirubin: negative

urobilinogen: negative

 The descrepancy between the large amount of blood and the absence of microscopy is caused by:

The presence of myoglobin in the urine sample

Myoglobin is a product of muscle distruction. The reagent strip reaction for blood is positive with the presence of RBCs hemoglobin , and myoglobin. Both hemoglobin and myoglobin are toxic to renal tubules , resulting in decreased urine flow , favoring cast formation and the sloughing of damaged cells. Notice also that the specimen is clear.

What is the most likely diagnosis given this microscopic finding?

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Identify the formed element in this photomicrograph:

waxy

Broad cast indicte extream stasis of urine flow through the nephron. Stasis allows cast to form in the larger collecting ducts. Damaage to the walls of the distal convouluted tubule also cause broader cast to form

A technologist performed a STAT microscopic urinalysis and reported the following

WBC: 10-13

RBC: 2-6

hyline cast: 5-7

bacteria: 1+

The centrafuge tube was not discarded and the sedament was reevaluated microscopically 5 hours after the above results are reported. A second technologist reported the same results except 2+ bacteria and no hyline cast were found. The most probable explanation for the second technologist findings is:

Cast dissolve due to an increase in urine Ph.

Multiplication of the bacteria caused the urine to become alkaline, causing the cast to dissolve

WBC cast

Plelonephritis is an inflammation /infection of the renal tubules. Therefore white blood cell cast would indicate the location of the source of the inflammation /infection . Cystitis is an infection of the bladder.

tubular necrosis

Damage to the renal tubules causes sloughing of the cell lining the tubules, making these cells the most promonent  in the cast formation, Although cast are seen in each of the other listed disorders, each has its own most promonient cast features ie red blood cells, fat, and white blood cells

renal tubular epithelial cells

The eccentric placement of the nucleus in renal tubular cells differentiates them from spherical urothelial cells , which have a centrally placed nucleus.

What is the most likely diagnosis given this microscopic finding?

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glomerulonephritis'

RBC cast, protein and RBCs together are indicative of glomerular nephritis. RBC cast form when there is bleeding in the glomerulus and tubules

amorphous phosphates

Amorphous phosphates are found in alkaline urine. Under conditions such as refrigeration, they produce a white precipitate. Urates produce a pink precipitate, and WBCs and bacteria do not precipitate.

cystine

cystine crystals appear as a hexogonal plates, frequently in clumps, Tyrosine crystals are needle shaped, leucine crystals are round and cholesteral crystals are flat with notched croners

calcium

Approximately 75% of renal calculi are composed of calcium compounds (oxalate, Phosphate and others). Magnesium ammonium phosphate makes up about 15% of the calculi

urates

Amorphous urates will dissolve when the specimen is breifly warmed. Amorphous phosphates are dissolved by the addition of acid, which will destroy other sediment constituents.

calcium carbonate

Calcium carbonate cryatals are small dumbell shaped or round crystals often seen in clumps. With careful examination,  dumbell shaped forms can be distinguished.

calcium oxalate

Calcium oxalate crystals are found in  in acidic and nutural urine, but not in alkaline urine.

cholesterol

Cholesterol is the only one of these lipids capable of polorizing light.

tyrosine

Tyrosine crystals are fine needles often seen in clumps. Leucine are spherical with concentric striations. Cholesterol  crystals are flat plates with notched corners. Hemosiderin granules are dark, and often clumped.

oval/dumbell

Calcium oxide monohydrate crystals are most frequently seen following ingestion of ethylene glycol/ antifreeze. Unlike the more commonly seen envelope-shaped diydrate crystals , they are oval or dumbell shaped.

4+ protein

Increased lipids in the urine is a characteristic of the nephroyic syndrome. Massive amounts of protein are also associated with the nephrotic syndrome.

could indicate Lesch-Nyhan syndrome

Lesch-Nyhan symdrome is an inherited disorder of purine metabolism. The first indication of this disorder may be the presence of uric acid indicating the incomple metabolism of dietary purines.

The following crystal is found in:

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Alkaline Ph and is non pathogenic

Triple phosphste crystals, nicknamed coffin lids are nonpathologic. They are found in alkaline urines, usually urines with bacterial growth.

Identify this crystal

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uric acid

Uric acid has many shapes, is found in acid urine and is non pathologic. The reader should become familiar with different shapes.

Alkaline urine showed this microscopic finding:

[image]

the technologist should:

dissolve with acetic acid

The crystals are amorphous phosphates.

These can be dissolved with dilute acetic acid. In order to view other formed elements that are obscured.

fibers and mucus clumps

Contaminants frequently contain substances capable of polorizing light.

The presence of this element in urine indicates the presence of:

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powder

Starch granules are very refractile and produce a maltese cross under polorized light, Oil air bubbles and pollon grains do not polorize

Identify the formed element in this photomicrograph:

[image]

cloth fiber

Cloth fiber is a contaminant it should noe be confused with a cast . Fiber can have a rough and stringy appearance. Vegatable fibers have intracate repeating detail

lyse  the red blood cells

Acetic acid lyses red blood cells, but not oil droplets or yeast. cetic acid will also lyse other formed elements and should be added to an aliquot of the settlement

A urine specimen is tested and has the following results:

Reagent strip                                   Microscopic findings

glucose 3+                                        >100 WBCs/hpf

Protein  1+                                        many yeast cells

This is indicative of:

Diabetes mellitis

Yeast cells are a commonly seen in urine specimens from persons with diabetes mellitus, because the high glucose contesn provides an excellant growth media for yeast.

pH

Urine crystals formation is associated with the optional pH needed for their formation (acid,alkaline or neutural).

lukocytes is positive

Based on the time between collection and analysis of a urine specimen and the method of preservation, bacteria can be a heavy contaminate of urine. A positive LE test indicating the actual presence of WBCs confirms the actual presence of an infection.

Trichomonas vaginalis

The flagellite Trichomonas vaginalis moves rapidly through the sediment . If not moving, it may resemble a WBC , and careful examination of phase microscopy is needed to visualize the flagellum, Urine is Toxic to spermatozoa

Which of the following is consistant with this urine microscopic finding?

[image]

nitrates

Many bacteria produce nitrites from nitrate. If the biochemical strip is positive for nitrite, you should find bacteria in the sediment

renal glucose uria

Glucose in the urine of a person with a normal blood glucose is indicative of renal tubule damage or the inherited disorder, renal glucoseuria, in which transport receptors are absent in thr proximal convoluted tubule

Complete examination:

A 59 year old man is evaluated for back pain. Urine studies (urinalysis by multiple reagent strip) should include:

Urinalysis

specific gravity:   1.017

pH:  6.5

protein: negative

glucose: negative

blood: negative

Microscopic findings

rare epithelial cells

Urine protein electrophoresis: monoclonal spike in gamma globulin region

Which of the following statements best explain these results?

Urine protein is falsley negative because the method is not sensitive ofr Bence Jones protein

Reagent strip test for proteinuria are primarily sensitive to albumin. The monoclonal spike in the gamma region indicates the presence of Bence jones protein that is immunoglobulin rather than albumin.

The results of a urinalysis on a first morning specimen are:

Specific gravity: 1.024

pH:  8.5

 protein  negative

glucose: negative

Microscopic findings

uric acid crystalsThe next step is to repeat the:

Ph and microscopic findings

Uric acid crystals are seen in acid urine. The reagent strip pH may have been recorded wrong . Uric acid crystals have many shapes, and an artifact may have been mistaken for the uric acid crystals.

The following urinalysis results were obtained from an 18 year old woman in labor:

pH;  6.5

protein:  30 mg/dL

glucose: 250 mg/dL

ketones: negative:

bilirubin:   small

blood: negative

nitrite: negative

urobilinogen: 0.1 EU/dL

specific gravity: 1.025

copper reduction test: 1.0 g/dL

Which of the following is the most likely explanation for the Patients positive copper reduction test?

Glucose and possibly other reducing substances/ sugars are present.

The reagent strip glucose test using glucose oxidase is specific for glucose; therefore, glucose must be present in the sample. The copper reduction test is positive with many sugars, including glucose . The copper reduction test has a lower sensitivity than the reagent strip; therefore , the higer reading on the copper reduction strip indicates of an additional sugar , In the case of a nursing mother, the most likely additional suger is lactose.

The following urine results were obtained on a 25 year old female:

pH: 7.0                         microscopic findings

color: yellow                bacteria:        many

appearance: cloudy      WBC cast: 0-3/lpf

protein: 1+                   WBC/hpf 30-40

glucose: negative

blood: small

specific gravity:  0.015

These results are most compatible with:       

pylonephritis

Pyelonephritis is an infection involving the renal tubules, Therefore, the presence of WBC cast and bacteria aids in the diagnosis, Cystitis is an infection of the bladder and does not affect the tubules. RBC cast are the promonent finding with glomerularnephritus.

A urinalysis performed on a 27 year old woman yields the following results:

specific gravity 1.008                microscopic findings

Ph:   5.0                                   WBC/hpf 10-15

protein: 2+                               RBC/hpf 30-55

glucose:  negative                 casts/lpf  hyline 5-7, RBC: 2- 5              

ketones: negative                      granular 2-3

bilirubin: negative

blood: 3+

nitrite: negative

leukocytes: positive

urobilinogen: 0.1 EU/dL

These findings are most consistant with:

glomerulonephritis

The presence of RBC cast is consistant with glomerularlonephritis. WBCs, RBCs and protein are a result of glomerular damage.

nephrotic symdrome

Damage to the electrical charges of the glomerular membrane , allowing the passage of high molecular weight proteins and lipids occurs in nephrotic syndrome. This results in markedly increased urine protein levels, and the appearance of fatty casts and oval fat bodies that are characteristic of nephrotic syndrome

A patient has two separate urinalysis reports which contain the following data:

Test                             Report A                         Report B

specific gravity               1.004                           1.017

pH;                                  5.5                                7.0

protein:                           negative                        1+

glucose:                          negative                         negative

blood:                             negative                         small

miscroscopy:                 rare epithelial cell           1-2 granular cast/lpf

                                                                               2-3 hylin cast /lpf

                                                                         moderate epithelial cells 

WHICH OF THE FOLLOWING BEST EXPLAINS THE RESULTS? 

protein , glucose and microscopy of A are false negative because of the specific gravity.

A specimen with a specific gravity of 1.004 is very dilute. This will result in the concentration of urine constituants being too low, below the ability to be detected by chemical and microscopic examination.

A 4 year old girl develops edema following a recent immunization. Laboratory studies reveal:

serum albumin:     1.8 g/dL

serum cholesterol:    450 mg/dL

serum urine nitrogen:   20 mg/dL

urinalysis:    protein 4+, hyline, granular and fatty cast

These findings are most compatible with:

minimal change disease

Minimal change disease is seen primarily in children, often following allergic reactions or immunizations. Classic  laboratory results include markedly elevated urine protein, fatty cast, elevated serum lipids, decreased serum albumin , and normal BUN.

acute interstitial nephritis

Acute interstitial nephritis is caused by an allergic reaction, resulting in inflammation, not infection , of the renal tubules. Bacteria are not present in an inflammation

Urinalysis results on a female patient who brings a urine specimen to the physician's office for her annual physical are:

color:  yellow                                                   Microscopic findings

clarity:  cloudy         

                                                              squamous epithelial cells 

                                                            moderate                                     

specific gravity: 1.020                                     WBC/hpf  0.2

pH: 7.0                                                         bacteria  heavy

protein: trace                      

glucose: negative

ketones: negative

blood: negative

bilirubin: negative

urobilinogen: 0.2 mg/dL

nitrite: positive

leukocytes: negative

What action should be taken:

ask the patient to collect another specimen at the office.

The presence of heavy bacteia with a negative leukocyte esterase and normal WBC numbers indicates the specimen has been collected > 2 hours before being tested. Testing a fresh specimen will determine if bacterial multiplicaton has occured in the first specimen.

A patient with lupus erythematosis has the following urinealysis results:

color:  red                          Microscopic findings

clarity: cloudy                 WBC/hpf    5-10                                             

specific gravity: 1.011      RBC/hpf   40-50

pH: 6.0                             Casts/lpf hyline 2-4, RBC 3-5

protein: 3+

glucose: negative

ketones: negative

blood: large

bilirubin: negative

urobilinogen: 1.0 mg/dL

nitrite: negative

leukocytes: trace

These results would be associated with:

chronic glomerulonephritis

A major cause of glomerular disorders is the deposition of immune complexes on the glomerular membrane, producing damage to the membranes. The presence of RBC cast would be present in chronic pyelonephritis, and renal tubular epithelial cells are present in tubular necrosis.

Candida albicans

The ideal growth conditions for growth of candida albicans are an acid pH and the presence of glucose. Candida is a frequent  cause of urinary tract infections in diabetic patients.

A patient with severe back pain has the following urinalysis results:

color: dark yellow                         microscopic findings

clarity: hazy                                   RBC/hpf    10-20

specific gravity 1.030                   squamous epi cells  moderate

pH: 6.0                                          calcium oxalate crystals

protein trace

glucose negative

ketones negative

bloos small 

bilirubin negative

urobilinogen 0.4 mg/dL

nitrite: negative

leukocytes: negative

In addition to the presence of blood, what other reagent strip result relates to the patients symptoms?

specific gravity

The high specific gravity indicates the patient is in a dehydrated state that favors the formation the formaton of renal calculi, producing back pain and the presence of red blood cells resulting from irritation to the urinary tract caused by the calculi

Urine physiology:

The normal  renal threshold for glucose in the adult is pporximately:

160 mg/dL

The renal threshold is the ploasma level at which a substance , such as glucose, is no longer absoebed by the proximal convoluted tubules. The plasma level for glucose ranges from 160-180 mg/dL

oligouria

The normal daily urine output is around 1200 mLs

diabetes mellitus

Polyuria occurs due to the need to excrete excess urine. The excess dissolved glucose in the urinary filtrate .

120 mL/min

Although the normal glomerular filtration rate is 120 mL/min, tubular reabsorption returns normally all but 1 mL

water, uria and sodium chloride

Protein molecules are too large to normally pass theough the glomerulus. Bilirubin is not a normal constituant of plasma

test for urea and creatinine

Urine is the ONLY body fluid containing large amounts of the  waste products urea and creatinine. These 2 constituants are used to determine if an unknown fluid is urine.

Antidiuretic hormone regulates the resorbtion of:

water.

Based on the bodys stae of hydration, anti dirutic hormone regulates the permeability of the walls of the collecting ducts to water , When the body is dehydrated, ADH is released by the pituitary gland, reducing the permeability of the walls to water.

Large molecular weight proteins

The intact structure of the glomerulae membrane does not permit passage of high molecular weight  substances, such as protein molecules.

diabetes mellitis

The increased lasma glucose seen in diabete mellitis results in excess hglucose in the glomerular filtrate. Increased amounts of water are required for excreation of the excess glucose in the filtrate. As a result, increased fluid intake is characteristic of persons with diabetes mellitis

galactose

Galactouria is an inborn error of metabolism, resulting in the failure to inherit one of the enzymes needed to metabolize diatary glucose. By products of this metabolic failure are toxic, and can result in severe mental retardation. Early detection and diatary changes can prevent the toxicity.

incomplete fat metabolism

Ketones are intermediate components  of fat metabolism. When access to carbohydrates normally broken down to supply energy is limited , fats are broken down for energy, and the intermediate ketone products (acetone, acetoacetic acid and beta hydroxybuteric acid) can be detected in the urine.

acetoacetic acid

The nitroprusside/ferricyanide reagent strip react with acetoacetic acid.Glycine must be present for the reaction to include acetone. beta-hydroxybutyric acid is present in the largest amount, but does not react with nitroferricyanide.

viral hepititis

Bilirubin is a product of hemoglobin degradaton. It occurs in both unconjugated  and conjugated forms. Only conjugated bilirubin can pass through the glomerulus, because unconjugated bilirubin is bound to albumin, Conjugation of bilirubin takse place in the liver, and damage interferes with continued degradation to urobilinogen.

 myocardial infarction

Myoglobin is a product of muscle destruction. Myocardial infarctions damage the heart muscle.

High Ph

Renal tublar acidosis is the inability to produce an acid urine even when in acidosis. The hydrogen ions needed to produce an acid urine are eaisly reabsorbed. To remove them, tubular secretion of the ions, combined with ammonium ions produced in the proximal tubule  and distal convoluted tubules , is needed.

renal tubular dysfunction

The majority of the filtered glucose is reabsorbed by active transport in the proximal convoluted tubules(PCT). Damage to the PCTs results in glucose uria and a normal plasma glucose.

ascending loop of Henle

To maintain the high concentration of solutes in the renal medulla that result in the ability to concentrate urine, water cannot be removed from the filtrate as it passes through the asceding loop of Henle

juxtamedullary nephrons

The juxtaaglomerular nephron have long loops of Henle, and the urinary filtrate passes through the renal medulla with its high osmotic gradient , causing resorption  of water in the decending loop of Henle. Corticol nephrons are located in the renal cortex and have short loops of Henle that do not reach the medulla.

osmolarity

Osmolarity measures the number of particles in a solution, whereas specific gravity is influenced not only by the number of particles but also their density. Renal concentration is concerned with smaller molecules , such as sodium and chloride. Each of these molecules will contribute  the same to an osmolarity reading as a large molecule of glucose. 

High Ph

The production of ammonia is essential fot the removla of hydrogen ions from the glomerular filtrate. Lack of ammonia results in a lack of hydrogen ions in the filtrate and a high pH.

Other body fluids:

To avoid falsley elevated spinal fluid cell counts:

select an aliquot from the last tube collected

The lumbar tap may be traumatic, which will produce blood. Blood cells in the CSF will not be due to a central nervous system defect in that case.

white blood cells

Protein and glucose are dissolved substances and dont contribute to turbidity. Bacteria and WBCs are solids that make the CSF turbid. When Bacteria is present so are WBCs. The large WBCs contribute more to turbidity than the smaller ones.

glacial acetic acid

Diluting cells for counting should not disturb them osmotically. Saline is the best choice. Water can lyse the cells, trichloroacetic acid will precipitate the sample, and acetic acid will form a clot with hyaluronic acid in the sample.

In addition to the sperm count in a fertility study, analysis of the seminal fluid should also include?

time of liquefaction, estimation of motility, morphology.

Its not necessary to test alkaline phosphatase, acid phophatase oe hemoglobin for fertility. Sperm should be motile ], have normal morphology and the sample sample should have normal viscosity.

The following lab values were obtained on a body fluid sample:

protein  3 g/dL

albumin 2.1 g/dL

hyaluronate: 0.4 g/dL

glucose 80 mg/dL

lactate: 10 mg/dL

The sample is:

synovial fluid

Urine and CSF are ruled out because of the high protein value. Urine and CSF have proteins in the mg/dL range NOT g/dL. Hyaluronate is a component of snovial fluid, not plural fluid.

haluronic acid clots in the presence of acetic acid

its snovial fluid

snovial fluid has hyuronic acid

Snyovial fluid is analyzed with a polorizing microscope . Strongly bifringent needles are seen.

This most likely indicates. 

monosodium urate cryatals

MSU (uric acid) are needles , whereas calcium pyrophosphate crystals are rhomboid and square. Corticosteroid crystals are bifringent and needle shaped but will only be present if the patient has been treated with corticosteriod injections. Talc crystals are found are found as contaminants, and are not needle shaped

hyluronate

Hyluronic acid is also known as hysluronate. It is the principle mucin in synovial fluid, and its role is lubrication of the joints , A low hyluronic acid leads ro decreased viscosity of the snovial fluid aand inflammation.

associated with inflammation

A n ormal synovial fluid is viscous and will form a string of 4-6 cm when expressedd from a syringe. If the fluid forms small drops, the viscosity is decreased . This is associated with arhtritis; hence, inflammation is the correct answer.

Relatively low cell counts

Transudates are thin , watery effusions with low protein, and low cell counts. Exudates are inflammatory of infectious effusions with high LD, protein and WBC

appear clear and pale yellow.

Congestive heart fluid is a build up of fluid because of poor heart pumping. The fliud is watery , not infected.

(MSU) and calcium pyrophosphate dehydrate (CPPD) crystals can be distinguished by using a red compensator in a polorizing microscope. When the crystals is aligned with a slow vibration of the compensator, which is true.

MSU are yellow.

uric acid produces a yellow color when the crystal is aligned with the compensator, but the color is blue when the crystal is perpendicular

CPPD has the oppisuite color effect.12

Horseradish.

False positives for fecal occult blood occur when patient diet includes foods that produces peroxidase. Horseradish, broccoli, radishes, melons, and other foods can cause a false positive. Patients that take asparin may have some occult bleeding that is not associated with colorectal cancer, but acetomenophen is not a cause of bleeding . Acsorbic acid at high doses  can interfere with test and cause a false negtive.

A bulidup of fluid in a body cavity is called :

Fetal lung maturity

Amniotic fluid can be collected to test for birth defects such as trisomy 21 (Down syndrome ) spina bifida (increased AFP and acetylcholinesterase) hemolytic disease of the newborn (bilirubin) and fetal lung maturity . FLM can be determined by increased lamillar body production  in the amniotic fluid. Lamellar bodies are phospholipids produced by the maturing pneumocytes. They are approximately the size of small platelets, and can be counted in instruments that count platelets.

delta F 508

Delta-F508 is the deletion of phenylalanune at position 508 of the CFTR protein. Trisomy 21 is a third copy of chromosome 21, associated with downs syndrome. The philidelphia chromosome is a gene translocation associated with acute myelocytic leukemia . Fragile X is a form of mental retardation caused by an increased number of neucleotide repeats.

Multiple sclerosis

The synthesis of IgG in the central nervous system is associated with some neurological disorders, most predominatelt multiple sclerosis. The other conditions are also CNS disorders, but do not cause increased plasma proteins.

synthesis of IgG in the CNS

The IgG index is used to determine if increased IgG in CSF is due to increased production in the CNS or contamination from a breach to the blood brain barrier. The calculation includes the CSF IgG/serum IgG ratio, and is normalized by dic=viding that by the CSF albumin/serum albumin

11

To calculate the dilution, take the amount of sample and divide it by the total of the new solution. So the dilution is 50uL divided by 500+50 uL. This is a 1:11 dilution. To correct the final answer, multiply by the inverse of the dilution  or 11.

Glucose 20 mg/dL(decreased), Protein 50 mg/dL (increased), Lactate increased.

Normal CSF glucose is approximately 60% of plasma glucose. Glucose is decreased in bacterial meningitis, and lactate is produced. Normal protein in CSF is 15-45 mg/dL. Protein is  slightly elevated in bacterial meningitis.

glutamine

In hepatic encephalopathy, ammonia levels in the plasma building up, and ammonia can be found in the spinal fluid. Ammonia is volitile, and not eaisly measured. Glutamine is a by product of ammonia , and is stable , making it a better choice.

PSA

Consider each answer and consider if it is unique to a particular site

eosin nigrosin

can differentiate between live and dead sperm

Living cells will stain bluish white and dead cells stain RED

3x3x0.1

The total volume of the 9 large cells is the equivalent of 1uL.Counting 10 of the large cells is the equivalent of 1 mL

During sweat collecton, a consideration that can result in a falsley high result is:

sweat conductivity`

sweat conductivity testing is relatively easy to peform, and is used as a screening method. A positive should be confirmed with a chloride measurement by coluometry, or by ion selective electrod. Pilocarpine iontrophoresis is used to stimulate sweat production, not to measure it.

Dark green - hemolytic disease of the newborn

Dark green amniotic fluid indicates THE PRESENCE OF MECONIUM. tHIS IS THE INFANTS FIRST BOWEL MOVEMENT, AND INDICATES FETAL DISTRESS

Flouresence polorizaton assay

The amount of surfactant (phospholipids) in amniotic fluid increases during gestaton, and is an indicator of fetal lung maturity. The value is compaired to albumin as albumin concentration remains constant during gestation. Fluoescent dye binds to surfactants and to albumin in this assay; when it is bound to the surfactant, it has a low polorization, As surfactant increases during lung maturaton, the flourescent polorization of the sample decreases. 

 CSF/albumin index

The CSF albumin ratio with a value of <9 indicates an intact blood brain barrier. The IgG index compares IgG in CSF and serum to determine if IgG is being synthesized in the CNS. The fluid serum LD ratio is used to determine if the body fluid is a transudate or an exudate. The albumin gradieent is used to determine if an effusion is of hepatic origin.