7.3 cerebrospinal, serous, and synovial fluids

Cerebrospinal fluid (CSF) is formed by ultrafiltration of plasma through the:

A. Choroid plexus
B. Sagittal sinus
C. Anterior cerebral lymphatics
D. Arachnoid membrane

A. Choroid plexus

Which statement regarding CSF is true?

A. Normal values for mononuclear cells are higher for infants than adults
B. Absolute neutrophilia is not significant if the total WBC count is less than 25/uL
C. The first aliquot of CSF should be sent to the microbiology laboratory
D. Neutrophils compose the majority of WBCs in normal CSF

A. Normal values for mononuclear cells are higher for infants than adults

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

A. Low CSF volume
B. Subarachnoid hemorrhage
C. Meningitis
D. Hydrocephalus

A. Low CSF volume

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

A. Clearing of the fluid as it is aspirated
B. A clear supernatant after centrifugation
C. Xanthochromia
D. Presence of a protein in the sample

C. Xanthochromia

The term used to denote a high WBC count in the CSF is:

A. Empyema
B. Neutrophilia
C. Pleocytosis
D. Hyperglycorrhachia

C. Pleocytosis

Which of the adult CSF values in the table below are consistent with bacterial meningitis?
Pattern: WBCs, Lymphs, Monos, Eos, PMNs, Neuroectodermal Cells

A. 50/uL, 44%, 55%, 0%, 0%, 1%
B. 300/uL, 75%, 21%, 3%, 0%, 1%
C. 2,000/uL, 5%, 15%, 0%, 80%, 0%
D. 2,500/uL, 40%, 50%, 0%, 10%, 0%

C.

WBCs: 2,000/uL
Lymphs: 5%
Monocytes: 15%
Eos: 0%
PMNs: 80%
Neuroectodermal Cells: 0%

Given the following data, determine the corrected CSF WBC count.

CSF RBCs: 6,000/uL Peripheral Blood RBCs: 4.0 x 10^6/uL
CSF WBCs: 150 /uL Peripheral Blood WBCs: 5.0 x 10^3/uL

A. 8/uL
B. 142/uL
C. 120/uL
D. 145/uL

B. 142/uL

Corrected WBC count = WBCs in CSF - [(Blood WBCs x CSF RBCs) / Blood RBCs]

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

CSF glucose: 20 mg/dL
CSF protein: 200 mg/dL
CSF lactate: 50 mg/dL (reference range 5 - 25 mg/dL)

A. Viral meningitis
B. Viral encephalitis
C. Cryptococcal meningitis
D. Acute bacterial meningitis

D. Acute bacterial meningitis

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

A. Multiple sclerosis
B. Malignancy
C. Subarachnoid hemorrhage
D. Viral meningitis

D. Viral meningitis

The diagnosis of MS is suggested by which finding?

A. The presence of elevated protein and low glucose
B. A decreased IgG index
C. The presence of oligoclonal bands by electrophoresis
D. An increased level of CSF beta-macroglobulin

C. The presence of oligoclonal bands by electrophoresis

Which of the following results is consistent with fungal meningitis?

A. Normal CSF glucose
B. Pleocytosis of mixed cellularity
C. Normal CSF protein
D. High CSF lactate

B. Pleocytosis of mixed cellularity

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

A. Cryptococcal meningitis
B. Amoebic meningitis
C. Mycobacterium tuberculosis infection
D. Neurosyphilis

B. Amoebic meningitis

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

A. Glutamine
B. Lactate
C. IgG index
D. Ammonia

C. IgG index

Which of the following is an inappropriate procedure for performing routine CSF analysis?

A. A differential is done only if the total WBC count is greater than 10/uL
B. A differential should be done on a stained CSF concentrate
C. A minimum of 30 WBCs should be differentiated
D. A Wright-stained slide should be examined rather than a chamber differential

A. A differential is done only if the total WBC count is greater than 10/uL

Which cell is present in CSF in greater number in newborns than in older children or adults?

A. Eosinophils
B. Lymphocytes
C. Monocytes
D. Neutrophils

C. Monocytes

Neutrophilia pleocytosis is usually associated with all of the following except?

A. Cerebral infarction
B. Malignancy
C. Myelography
D. Neurosyphilis

D. Neurosyphilis

Which statement about CSF protein is true?

A. An abnormal serum protein electrophoretic pattern does not affect the CSF pattern
B. The upper reference limit (URL) for CSF total protein in newborns is one half the adult level
C. CSF IgG is increased in panencephalitis
D. Antibodies to Treponema pallidum disappear after successful antibiotic therapy

C. CSF IgG is increased in panencephalitis

Which of the following statements regarding routine microbiological examination of CSF is true?

A. A gram stain is performed on the CSF prior to concentration
B. The gram stain is positive in fewer than 40% of cases of acute bacterial meningitis
C. India ink and acid fast stains are indicated if neutrophilia pleocytosis is present
D. All CSF specimens should be cultured using sheep blood agar, chocolate agar, and supplemented broths

D. All CSF specimens should be cultured using sheep blood agar, chocolate agar, and supplemented broths

Which organism is the most frequent cause of bacterial meningitis in neonates?

A. Neisseria meningitidis
B. Group B Streptococcus
C. Haemophilus influenzae
D. Klebsiella pneumoniae

B. Group B Streptococcus

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

A. Transthyretin
B. Myelin basic protein
C. Tau protein
D. C-reactive protein

C. Tau protein

Which of the following statements regarding serous fluids is true?

A. The normal volume of pleural fluid is 30 to 50 mL
B. Mesothelial cells, PMNs, lymphocytes, and macrophages may be present in normal fluids
C. Radiography can detect a 10% increase in the volume of a serous fluid
D. Normal serous fluids are colorless

B. Mesothelial cells, PMNs, lymphocytes, and macrophages may be present in normal fluids

The term effusion refers to:

A. A chest fluid that is purulent
B. A serous fluid that is chylous
C. An increased volume of serous fluid
D. An inflammatory process affecting the appearance of a serous fluid

C. An increased volume of serous fluid

Which of the following laboratory results is characteristic of a transudative fluid?

A. SG = 1.018
B. Total protein = 3.2 g/dL
C. LD fluid/serum ratio = 0.25
D. Total protein fluid:serum ratio = 0.65

C. LD fluid/serum ratio = 0.25

Which observation is least useful in distinguishing a hemorrhagic serous fluid from a traumatic tap?

A. Clearing of fluid as it is aspirated
B. Presence of xanthochromia
C. The formation of a clot
D. Diminished RBC count in successive aliquots

C. The formation of a clot

Which of the following laboratory results on a serous fluid is most likely to be caused by a traumatic tap?

A. An RBC count of 8,000/uL
B. A WBC count of 6,000/uL
C. A hematocrit of 35%
D. A neutrophil count of 55%

A. An RBC count of 8,000/uL

Which of the following conditions is commonly associated with an exudative effusion?

A. Congestive heart failure
B. Malignancy
C. Nephrotic syndrome
D. Cirrhosis

B. Malignancy

Which of the following conditions is associated with a chylous effusion?

A. Necrosis
B. Pulmonary infarction or infection
C. Systemic lupus erythematosus or rheumatoid arthritis (RA)
D. Lymphatic obstruction

D. Lymphatic obstruction

Which of the following conditions is most often associated with a pleural fluid glucose below 30 mg/dL?

A. Diabetes mellitus
B. Pancreatitis
C. Rheumatoid arthritis
D. Bacterial pneumonia

C. Rheumatoid arthritis

In which condition is the pleural fluid pH likely to be above 7.3?

A. Bacterial pneumonia with parapneumonic exudate
B. Rheumatoid pleuritis
C. Esophageal rupture
D. Pneumothorax

D. Pneumothorax

Which of the following hematology values best frames the URLs for peritoneal fluid?

Pattern: WBC Count, Percentage of PMNs, RBC Count

A. 300/uL, 25%, 100,000/uL
B. 10,000/uL, 50%, 500,000/uL
C. 50,000/uL, 50%, 500,000/uL
D. 100,000/uL, 75%, 1,000,000/uL

A.

WBC Count: 300/uL
Percentage of PMNs: 25%
RBC Count: 1,000,000/uL

Which of the following characteristics is higher for synovial fluid than for the serous fluids?

A. Specific gravity
B. Glucose
C. Total protein
D. Viscosity

D. Viscosity

In which type of arthritis is the synovial WBC count likely to be greater than 50,000/uL?

A. Septic arthritis
B. Osteoarthritis
C. Rheumatoid arthritis
D. Hemorrhagic arthritis

A. Septic arthritis

What type of cells is a "ragocyte"?

A. Cartilage cell seen in inflammatory arthritis
B. A PMN with inclusions formed by immune complexes
C. A plasma cell seen in RA
D. A macrophage containing large inclusions

B. A PMN with inclusions formed by immune complexes

Which of the following crystals is the cause of gout?

A. Uric acid or monosodium urate
B. Calcium pyrophosphate or apatite
C. Calcium oxalate
D. Cholesterol

A. Uric acid or monosodium urate

Which crystal causes "pseudogout"?

A. Oxalic acid
B. Calcium pyrophosphate
C. Calcium oxalate
D. Cholesterol

B. Calcium pyrophosphate

A synovial fluid sample is examined by using a polarizing microscope with a red compensating filter. Crystals are seen that are yellow when the long axis of the crystal is parallel to the slow vibrating light. When the long axis of the crystal is perpendicular to the slow vibrating light, the crystals appear blue. What type of crystal is present?

A. Calcium oxalate
B. Calcium pyrophosphate
C. Uric acid
D. Cholesterol

C. Uric acid

In which condition is the synovial fluid glucose most likely to be within normal limits?

A. Septic arthritis
B. Inflammatory arthritis
C. Hemorrhagic arthritis
D. Gout

C. Hemorrhagic arthritis

Which statement about synovial fluid in RA is true?

A. Synovial:serum IgG is usually 1:2 or higher
B. Total hemolytic complement is elevated
C. Ninety percent of RA cases test positive for rheumatoid factor in synovial fluid
D. Demonstration of rheumatoid factor in joint fluid is diagnostic for RA

A. Synovial:serum IgG is usually 1:2 or higher

Which of the following organisms accounts for the majority of septic arthritis cases in young and middle-age adults?

A. H influenzae
B. Neisseria gonorrhoeae
C. Staphylococcus aureus
D. Borrelia burgdorgeri

B. Neisseria gonorrhoeae

Which of the following hematology values best frames the URLs for synovial fluid?

Pattern: WBC Count, Percentage of PMNs, RBC Count

A. 200/uL, 25%, 2,000/uL
B. 5,000/uL, 50%, 10,000/uL
C. 10,000/uL, 50%, 50,000/uL
D. 20,000/uL, 5%, 500,000/uL

A.

WBC Count: 200/uL
Percentage of PMNs: 25%
RBC Count: 2,000/uL