Medical Laboratory Technician Urinalysis and Body Fluids Questions and Answers

Question 1

A technologist examining a urine sediment under a microscope observes numerous small, round, colorless structures. Some of these structures appear to be budding. Which of the following actions would best differentiate yeast from red blood cells?

Accepted Answer

Add a drop of dilute acetic acid to the sediment.

Answer

Adding dilute acetic acid will lyse red blood cells due to their lack of a cell wall, while the rigid cell wall of yeast will remain intact. This allows for clear differentiation when the two are similar in appearance.

Question 2

A cerebrospinal fluid (CSF) sample is received in the laboratory from a patient with a suspected subarachnoid hemorrhage. After centrifugation, the supernatant appears pale pink-yellow. This coloration is referred to as:

Accepted Answer

Xanthochromia

Answer

Xanthochromia is the term for the pink, orange, or yellow discoloration of CSF supernatant. It is caused by the breakdown of red blood cells and the subsequent release of hemoglobin degradation products like bilirubin, which indicates that bleeding occurred in vivo (e.g., a subarachnoid hemorrhage) rather than from a traumatic tap.

Question 3

A urine reagent strip test is positive for bilirubin. Which of the following is the most appropriate confirmatory test for this finding?

Accepted Answer

Ictotest tablet test

Answer

The Ictotest is a tablet-based diazo reaction test that is more specific and sensitive for urinary bilirubin than the reagent strip method. It is used to confirm positive bilirubin results and rule out false positives caused by interfering substances.

Question 4

A synovial fluid aspirate from a patient with acute joint pain is examined using compensated polarized light microscopy. The technologist observes strongly birefringent, needle-shaped crystals that appear yellow when aligned parallel to the slow axis of the compensator. These findings are characteristic of:

Accepted Answer

Monosodium urate (MSU) crystals

Answer

Monosodium urate (MSU) crystals are characteristically needle-shaped and exhibit strong negative birefringence. Under a compensated polarizing microscope, they appear yellow when their long axis is parallel to the slow axis of the red compensator, which is a classic diagnostic finding for gout.

Question 5

The presence of numerous waxy casts in a urine sediment analysis is most strongly associated with which of the following conditions?

Accepted Answer

Chronic end-stage renal disease

Answer

Waxy casts represent the final stage of cast degeneration (from cellular to granular to waxy). Their presence indicates extreme urine stasis and tubular damage, and they are most commonly found in patients with severe, long-standing chronic renal failure.

Medical Laboratory Technician Exam Practice Test

Medical Laboratory Technician Exam Practice Test

Medical Laboratory Technician Urinalysis and Body Fluids Questions and Answers