CSF

Where does most cerebrospinal fluid (CSF) originate?

choroid Plexus

Which of the following are characteristics of normal CSF?

clear and colorless

The image is a Wright-Giemsa stained smear (1000x) of cerebrospinal fluid (CSF). The arrows point to cells that may indicate which of the following conditions? (pointing to blast cells)

leukemia with CNS involvement

Viral meningitis

lymphocytic pleocytosis

A technologist decides to make a 1:20 dilution of cerebrospinal fluid (CSF) after briefly evaluating a portion of the sample microscopically. After making the dilution and charging the chambers, the number of cells that are observed in each of the large squares of the hemocytometer is >100. What should the technologist do to obtain the most accurate count?

make a larger dilution

Bone marrow contamination of the CSF

nRBCs

When preparing a slide for morphologic examination, what is the reason for adding a drop of albumin to the cerebrospinal fluid (CSF) sample prior to cytocentrifugation?

preserve cell integrity and morphology

Upon centrifugation, a cerebrospinal fluid (CSF) sample supernatant exhibited xanthochromia. The image is a Wright-Giemsa stained smear that was made from that CSF sample. What condition is probably related to these macroscopic and microscopic findings?

previous subarachnoid hemorrhage (SAH)

Clear cerebrospinal fluid samples should be examined and counted undiluted.

true

Cytocentrifugation is the recommended method for preparing a cerebrospinal fluid (CSF) sample for examination of cellular morphology.

true

Xanthochromia in a premature infant may be due to an immature blood-brain barrier.

true

Increased numbers of the cells indicated by the arrows are associated with which of these conditions? (pointing to lymphocytes)

viral meningitis

What is the approximate volume of spinal fluid in an adult?

90-150 mL

Which of the following is NOT a function of CSF? Supply nutrients to nervous system tissue. Regulate body metabolism. Protect spinal cord from injury. Remove waste products from cerebral metabolism.

Regulate body metabolism.

These 3 tubes of cerebrospinal fluid (CSF) are delivered to the laboratory for analysis. The tube labeled #1 was the first tube collected. Which one of the tubes should be used by the hematology department for cell count and differential?

Tube 3

A cell count is ordered on a CSF sample that is bloody. Which of the following procedures would improve count accuracy?

Use Spinal Diluting Fluid, a mixture of acetic acid and crystal violet. Use phase microscopy.

Lymphocyte pleocytosis refers to...

an increased number of lymphocytes in a CSF when compared to a normal sample.

A spinal fluid that is slightly hazy is briefly examined microscopically. The technologist performing the count decides to make a 1:10 dilution using 30 µL of sample. What volume of diluent should be used?

270 microliters

A sample of cerebrospinal fluid is diluted 1:100; the standard 9 squares of a hemocytometer are counted on each side for a total of 18 large squares. Side 1-- 186 nucleated cells counted Side 2-- 184 nucleated cells counted total nucleated cells = 370 Using the standard hemocytometer formula shown on the right, what is the nucleated cell count per microliter (µL)?

2.06 x 10^4

In a moderately bloody specimen, 250 cells are counted in 10 squares. The dilution is 1:100. What is the count/µL?

25,000

How many white blood cells (WBCs) would be considered normal for adult cerebrospinal fluid?

0-5 WBCs

Cell counts on CSF specimens should be performed within what time frame following collection of the CSF sample?

1 hour

A 1:10 dilution is made on a CSF sample. Five squares on each side of the hemocytometer are counted for a total of 10 squares and a total of 150 cells are recorded. What is the count per microliter (µL)?

1500

Previous subarachnoid hemorrhage (SAH)

Hemosiderin deposits

Which of the following sites is used most often for CSF collection?

L3-L4

Normal adult CSF may have 0-5 white blood cells (WBCs)/µL. Which of the following cell types account for 60-100% of these WBCs?

Lymphocytes

Which of the following situations suggest a traumatic tap occurred?

More blood is in tube 1 than tubes 2, 3 or 4. Blood clots are present.

Bacterial meningitis

Neutrophilic pleocytosis