Body Fluids exam 3

An HIV-positive patient develops edema, elevated cholesterol and triglyceride levels, heavy proteinuria, and deposits of immunoglobulin M and C3

Focal Segmental Glomerulosclerosis (FSGS)

A nephrotic syndrome variant often associated with HIV infection. Presents with:

Heavy proteinuria, edema, hypelipidemia, depositions of IgM and C3 in glomeruli. (p. 283-285)

Hyperlipidemia

Increased cholestrol

The CSF/Serum albumin index is useful in determining which of the following?

Breach in the blood-brain barrier

A patient with a history of intermittent hematuria following strenuous exercise has an elevated serum immunoglobulin A level.

IgA Nephropathy (Berger’s Disease)

Characterized by recurrent hematuria, often after exercise or infection, and elevated serum IgA due to immune complex deposition in the mesangium

Following ingestion of mushrooms found grow in in his garden, a man develops symptoms of oliguria, lethargy, and edema. Many RTE cells are observed in his urinalysis.

Acute Tubular Necrosis (ATN)

Certain mushrooms (amanita phalloides) contain nephrotoxins that cause tubular epithelial necrosis; RTE cells in urine, oliguria, edema, and renal failure

A patient whose microalbumiuria has progressed to a 2+ urine protein

Diabetic Nephropathy

Microalbuminuria is the earliest indicator of diabetic renal damage. Proteinuria this indicated worsening glomerular basement membrane damage due to chronic hyperglycemia.

An eosinophil count may be requested on urine from a patient with suspected:

Acute Interstitial Nephritis (AIN)

Urinary Eosinophils are a hallmark finding, cause by allergic-type inflammation in the renal interstitium

A 40-year-old female tennis player with tendonitis is taking large doses of an over-the-counter nonsteroidal anti-inflammatory agent. After taking the medication for several weeks, she develops a skin rash and observes a decrease in urine volume. Results of her urinalysis are:

Color: Dark yellow​

Protein: 1+

Blood: Trace    

Clarity: Slightly cloudy

Glucose: Neg

Urobilinogen: Normal  

Specific gravity: 1.025

Ketones: Neg

Nitrite: Neg

pH: 6.5

Bilirubin: Neg

​Leukocyte esterase: 2+

 

Microscopic

WBCs/hpf   20-50

Hyaline casts/lpf​​ Few

RBCs/hpf    0-5

WBC casts/lpf​​ 1-3

RTE/lpf Few

 

What is the most diagnostic reagent strip result in this urinalysis?

Positive Leukocyte Esterase (LE) without nitrite

LE detects WBC (especially eosinophils) in urine. In drug-induced AIN, the LE is positive even though no bacteria is present.

A 40-year-old female tennis player with tendonitis is taking large doses of an over-the-counter nonsteroidal anti-inflammatory agent. After taking the medication for several weeks, she develops a skin rash and observes a decrease in urine volume. Results of her urinalysis are:

Color: Dark yellow​

Protein: 1+

Blood: Trace    

Clarity: Slightly cloudy

Glucose: Neg

Urobilinogen: Normal  

Specific gravity: 1.025

Ketones: Neg

Nitrite: Neg

pH: 6.5

Bilirubin: Neg

​Leukocyte esterase: 2+

 

Microscopic

WBCs/hpf   20-50

Hyaline casts/lpf​​ Few

RBCs/hpf    0-5

WBC casts/lpf​​ 1-3

RTE/lpf Few

How does your above answer correlate with the microscopic results?

Correlates with a sterile pyuria pattern, which fits interstitial inflammation rather than than a UTI.

A 40-year-old female tennis player with tendonitis is taking large doses of an over-the-counter nonsteroidal anti-inflammatory agent. After taking the medication for several weeks, she develops a skin rash and observes a decrease in urine volume. Results of her urinalysis are:

Color: Dark yellow​

Protein: 1+

Blood: Trace    

Clarity: Slightly cloudy

Glucose: Neg

Urobilinogen: Normal  

Specific gravity: 1.025

Ketones: Neg

Nitrite: Neg

pH: 6.5

Bilirubin: Neg

​Leukocyte esterase: 2+

 

Microscopic

WBCs/hpf   20-50

Hyaline casts/lpf​​ Few

RBCs/hpf    0-5

WBC casts/lpf​​ 1-3

RTE/lpf Few

What additional test might be requested on this specimen?

Urine eosinophils stain (Hansel stain)

Eosinophiluria is a hallmark of Acute interstitial Nephritis. If present, it confirms hypersensitivity reaction to NSAIDS or other drugs

A 40-year-old female tennis player with tendonitis is taking large doses of an over-the-counter nonsteroidal anti-inflammatory agent. After taking the medication for several weeks, she develops a skin rash and observes a decrease in urine volume. Results of her urinalysis are:

Color: Dark yellow​

Protein: 1+

Blood: Trace    

Clarity: Slightly cloudy

Glucose: Neg

Urobilinogen: Normal  

Specific gravity: 1.025

Ketones: Neg

Nitrite: Neg

pH: 6.5

Bilirubin: Neg

​Leukocyte esterase: 2+

 

Microscopic

WBCs/hpf   20-50

Hyaline casts/lpf​​ Few

RBCs/hpf    0-5

WBC casts/lpf​​ 1-3

RTE/lpf Few

What is the probable diagnosis?

Acute Interstitial Nephritis (AIN) secondary to NSAID use.

Key findings: Rash, oliguria after NSAIDs, Positive LE, negative nitrite, and WBC casts

NSAIDs cause immune-mediated inflammation of the renal interstitium leading to infiltration of WBCs (mainly eosinophils) causing tubular dysfunction decreasing urine output.

It’s reversible if the drug is stopped early

Which blood test result below is used to confirm the diagnosis of acute glomerulonephritis?

Serum Complement (C3) levels

GN involved immune complex deposition that activated complement.

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

​​Clarity: Cloudy ​

Specific gravity:​ 1.020

pH: 7.0

Protein​: Neg

​Glucose: Neg

​Ketones: Neg

Blood:​ Neg

Bilirubin: Neg

Urobilinogen:​ Normal

Nitrite: Positive

Leukocyte esterase: Positive

Microscopic

Squamous epithelial cells:​ Many

​WBC/hpf​​: 5-10

Bacteria: Many

 

What action should be taken?

Reject specimen and request recollection

Microscopic urinalysis findings with Acute Interstitial Nephritis include all except

RBC Cast

Occur in glomerul disease, not AIN

In diabetic nephropathy, which solid material is deposited around the capillary tufts?

Kimmelstiel-Wilson nodules (hyaline material)

In diabetic nephropathy, the glomerular basement membrane thickening and nodular glomerulosclerosis lead to hyaline deposits around apillry tufts

Which of thee following can differentiate cystitis from pyelnephritis?

Presence of WBC casts

Oval fat bodies and fatty casts are characteristic of:

Nephrotic syndrome

Massive protein loss leads to loss in urine leading to oval fat bodies, fatty casts, and Maltese cross under polarized light

Build of crescentic formations on glomerular capillaries is characteristic of:

Rapidly progressive glomerulonephritis

Indicates severe, rapidly progressing immune-mediated GN

A patient with SLE has the following urinalysis results:

Color: red or smokey brown

​​Clarity: ​Cloudy

Specific gravity: 1.020

pH: ​​6.0

Protein:​​ 3+

Glucose:​ Negative

​Ketones: Ketones

Blood:​ 3+

​Bilirubin:  Negative

​Urobilinogen:​ Normal

Nitrite: Negative

Leukocyte esterase: +

Microscopic

RBC/hpf: >50 ​​

WBC/hpf:​​ 0-20

Cast/lpf : Hyaline, rbc casts; BC casts

These results would be associated with:

Lupus nephritis (immune complex glomerulophritis

Key findings: poteinuria, hematuria, and

RBC cast

State two reasons for the appearance of overflow metabolites in the urine.

Increased plasma concentration of a metabolite that exceeds the renal tubular absorption threshold.

Genetic or acquire metabolic defect that causes accumulation of an abnormal metabolite

What is the most common cause of acquired porphyria?

Lead poisoning

Lead inhibits ALA dehydratase and ferrochelatase, two enzymes in heme synthesis leading to buildup of porphyrin pre-coursers and porphyrin

Name two physical characteristics or urine that can alert medical personnel to the possibility of a metabolic disorder.

Unusual color

Characteristic odor

Metabolic defects often produce unique chromogens or volatile compounds that change urine’s color and odor

Phenylketonuria is cause by

A deficiency of the enzyme phenylalanine hydroxylase

Without this enzyme, phenlyalanine cannot convert to tyrosine, leading to accumulation of phenylpyruvic acid and mental impairment if untreated

When performing a Guthrie test

When performing a Guthrie bacterial inhibition assay, phenylalanine in the patient’s blood counteracts the inhibitory effect of the medium, allowing bacterial growth around the sample disc — indicating phenylketonuria (PKU).

Which of the following below are epithelial casts are most indicative?

Renal tubular epithelial casts

RTE casts indicate tubular injury or necrosis, often seen in acute tubular necrosis, toxic injury, or viral infections; most indicative of tubular damage.

The following urinalysis results are obtained from a newborn:

Color: Yellow

Protein: Neg

Blood: Neg

Clarity: Clear

Glucose: Neg

Urobilinogen: Normal

Specific Gravity: 1.015

Ketones: Neg

Nitrite: Neg

pH: 6.0

Bilirubin: Neg

Leukocytes Esterase: Neg

Clinitest: Positive 

What additional unusual characteristics might be found in this urine?

Mousy or musty odor

The following urinalysis results are obtained from a newborn:

Color: Yellow

Protein: Neg

Blood: Neg

Clarity: Clear

Glucose: Neg

Urobilinogen: Normal

Specific Gravity: 1.015

Ketones: Neg

Nitrite: Neg

pH: 6.0

Bilirubin: Neg

Leukocytes Esterase: Neg

Clinitest: Positive 

What screening test should be preformed on this specimen?

Guthrie test for PKU 

Used to detect elevated phenylaline levels in newborn blood.

Clinitest positive result alerts the lab to a metabolic problem.

The following urinalysis results are obtained from a newborn:

Color: Yellow

Protein: Neg

Blood: Neg

Clarity: Clear

Glucose: Neg

Urobilinogen: Normal

Specific Gravity: 1.015

Ketones: Neg

Nitrite: Neg

pH: 6.0

Bilirubin: Neg

Leukocytes Esterase: Neg

Clinitest: Positive 

What is the infant’s most probable disorder?

Phenylketonuria

Key findings “Mousy” smell, and positive Clinitest results.

Appropriate screening test result for PKU

Positive Guthrie test result

Detects elevated phenylalanine levels.

Appropriate screening test result for Tyrosyluria

Nitrosonaphtol test

Detects excess tyrosine/metabolites

Appropriate screening test result for Porphobilinogen

Elrich’s reaction Positive

Detects porphobilinogen in urine

Appropriate screening test result for Homocytinuria

Cyanide-nitroprusside test

Detects elevated homocysteine levels.

Appropriate screening test result for Hurler’s Syndrome

Positive acid-albumin or cetyltrimethylammonium bromide turbidity

Detects glycosaminoglycans in urine.

Appropriate screening test result for Alkapyonuria

Positive urine test for homogentisic acid . Urine turns black upon standing or with addition of alkali

A false-positive reaction for urinary ketones could be present in:

Drugs containing sulfhydryl groups

Characteristic odor for patient with PKU

Mousy or musty

Characteristic odor for patient with Tyrosinemia

Rancid or fishy

Characteristic odor for patient with cystinosis

No indicative odor but may have a garlic-like odor due to cystine accumulation.

Characteristic odor for patient with Isovaleric acidemia

Sweaty or stinky feet

Characteristic odor for patient with Maple syrup urine disease

Sweet, maple syrup-like odor

A routine urinalysis is performed on specimen that has turned brown after standing in the laboratory. The urine is acidic and has negative chemical tests except for the appearance of a color on the ketone area of the reagent strip. One should suspect:

Inhibition of bacterial growth in the Guthrie test should be interpreted as:

Normal (negative)

Abnormal amounts of indigo blue in the urine are indicative of a defect in the metabolism of

Tryptophan

Occurs in conditions like hartnup disease or intestinal obstruction

Which statement regarding CSF is true?

CSF is produced in the choroid plexus and provides cushioning for the brain and spinal cord.

Which of the following findings is consistent with a subarachnoid hemorrhage rather than a traumatic tap?

Xanthochromia and even distribution of RBCs in all collection tubes

Which of the following can be used to identify a fluid as CSF?

Presence of B2-transferrin (tau protein)

Which of the adult CSF values in the following table are consistent with bacterial meningitis?

WBC: increased (1,000-10,000/uL)

Lymph: decreased

Mono: decreased

Eos: zero

Neutrophil: increased

Neuroectodermal cells: absent

Elevation of WBCs and neutrophils, with marked lymphocyte decrease indicates bacterial infection.

Oligoclonal bands are significant in the diagnosis of the multiple sclerosis when:

Present in the CSF but not in serum.

What is the most likely cause of the following CSF results?

CSF glucose: decreased

CSF protein: increased

CSF lactate: increased

Decreased glucose=bacterial consumption

Increased protein=increased permeability of BBB

Increased lactate= anaerobic metabolism by bacteria and leukocyte

Which of the following conditions is most often associated with normal CSF glucose and protein?

Viral meningitis

Three tubes of CSF are submitted to the laboratory. They are numbered 1, 2, 3 and all show blood in all tubes but decreasing in amount in tubes 1 through 3. This observation should be interpreted as:

Traumatic tap

An IgG index greater than 0.08 is indicative of which of the following?

Increased intrathecal IgG synthesis, typically seen in multiple sclerosis or other central nervous system infections.

Which of the following can decrease CSF protein?

Administration of diuretics or corticosteroids or leakage or chronic fluid loss

When collecting CSF, a difference between opening and closing fluid pressure greater than 100 mm H2O indicates:

a possible obstruction in the cerebrospinal fluid pathways, such as a mass lesion or folly!

Which of the following CSF test results is most commonly increased in patient with MS?

Oligoclonal bands and myelin basic proteins

In what suspected condition should a wet prep using a warm slide be examined?

Amoebic meningoencephalitis

The diagnosis of MS is suggested by which findings?

Oligoclonal bands in the cerebrospinal fluid, elevates IgG index, and myelin basic protein

Following a head injury, which protein will identify the presence of CSF leakage through the nose?

Beta-2 transferrin

Which of the adult CSF values in the following table are consistent with bacterial meningitis?

Glucose:

Protein:

Lactase:

Decreased glucose=

Increased protein=

Increased lactase=

Given the following information, calculate the CSF

WBC count:

Cells counted:

Dilution

Large Neubauer squares counted

(Cells x Dilution) / (Squares x 0.9)

In plasma, the second most prevalent protein is IgG; in CSF, the second most prevalent protein is:

Transthyretin (prealbumin)

The finding of oligoclonal bands in the CSF and not in the serum is seen with:

Multiple sclerosis

A patient with a blood glucose of 120 mg/dL would have a normal CSF glucose of:

Approximately 60 mg/dL

Given the following results, calculate the IgG index:

(CSF IgG / Serum IgG) / (CSF Albumin / Serum Albumin)

What is the CSF igG index indicative of?

CFS IgG production. It reflects the degree of intrathecal IgG synthesis, indicating whether there is abnormal IgG production within the central nervous system.

CSF can be differentiated from plasma by the presence of:

B2-transferrin

A 55-year-old man is brought to the emergency room in a comatose state. He was found at home by his son and appears to have fallen from a ladder. A spinal tap is performed and revealed the following:

Color:

Appearance:

RBC:

WBC:

Differential WBC

Which of the following would be the most specific finding in this patient for a true CFS hemorrhage versus Traumatic spinal tap?

Xanthochromia in the CSF

What is the significance of the WBC count of XX 10^9/L?

Elevated WBC count in the CSF may indicate infection or inflammation, such as meningitis or encephalitis.

A CSF that appears orange should be described as:

Xanthochromic.

Increased protein urine

Renal disease, glomerulonephritis, nephrotic syndrome

Increased urine glucose

Diabetes mellitus or renal glycosuria

Increased Ketones in urine

Diabetic ketoacidosis

Increased urine bilirubin

Liver disease, bile duct obstruction

Increased urine urobilinogen

Liver disease or hemolytic anemia

Increased Nitrite

Bacterial UTI

Increased Leukocyte esterase

Pyelonephritis

Increased urine RBCs 3</hpf

Glomerular disease

Increased WBC >5/hpf

Infection/inflammation

Increased epithelial cells

Tubular injury

RBC casts

Glomerulonephritis

WBCs cast

Pyelonephritis

RTE casts

ATN

Fatty casts

Nephrotic syndrome

CSF opening pressure greater than 180 mm

Meningitis hemorrhage

CSF lower than 90 mm

Leakage

CSF blood count higher than 5uL

Meningitis

Neutrophils= bacteria

Lymphs= viral

Protein greater that 45 mg/dL

Meningitis, Multiple sclerosis, and hemorrhage

Protein less than 15 mg/dL

Leakage

Glucose lower than 45 mg/dL

Bacterial/ TB meningitis

CSF lactate greater than 35 mg/dL

Bacterial/ fungal/ TB meningitis

CSF IgG index greater than 0.8

Intrathecal IgG synthesis, multiple sclerosis

CSF myelins basic protein greater than 5 ng/mL

Demyelination (Multiple sclerosis)

Acidic + dark (urine)

Melanin

Alkaline + black (urine)

Alkaptonuria

CSF WBC Count Formula

(Cells counted × Dilution) ÷ (Squares counted × 0.9)

Explanation: Calculates WBCs per µL in CSF using a Neubauer chamber.

CSF RBC Count Formula

Same formula as WBC count.

Explanation: Used to quantify RBC contamination or hemorrhage. Compare tube 1 vs tube 3 to distinguish traumatic tap (↓ count).

Corrected CSF WBC Count (for Traumatic Tap)

Corrected WBC = Measured WBC – [(Peripheral WBC × CSF RBC) / Peripheral RBC]

Explanation: Removes falsely elevated WBCs caused by blood contamination.

Example: 40 – [(8,000 × 5,000) / 5,000,000] = 32 corrected WBCs/µL.

CSF IgG Index Formula

(CSF IgG / Serum IgG) ÷ (CSF Albumin / Serum Albumin)

Explanation: Detects intrathecal (CNS) IgG production.

Interpretation: ≤ 0.7 = Normal

> 0.8 = Multiple sclerosis or CNS inflammation

CSF IgG Index Example

(6 / 800) ÷ (20 / 4000) = 0.0075 ÷ 0.005 = 1.5

Explanation: Elevated → CNS IgG synthesis (e.g., MS).

CSF Glucose Ratio

CSF glucose ≈ ⅔ plasma glucose

Explanation: Compare blood and CSF glucose to assess barrier function.

Example: Blood glucose = 120 mg/dL → Normal CSF ≈ 60–80 mg/dL

<50% of plasma glucose = Bacterial meningitis or maligna