CCMA Laboratory Procedures 4

Question 1

Which additive is found in a light blue (sodium citrate) tube and is used for coagulation studies?

Accepted Answer

Sodium citrate

Answer

Light blue top tubes contain sodium citrate, which chelates calcium to prevent clotting and is the required anticoagulant for PT, PTT, and INR testing.

Question 2

A patient's urine dipstick shows a positive result for nitrites. This finding is MOST suggestive of:

Accepted Answer

Gram-negative bacterial infection

Answer

Nitrites on a urine dipstick indicate that bacteria (typically gram-negative) have converted urinary nitrates to nitrites, suggesting a urinary tract infection.

Question 3

When performing a capillary puncture on an infant, which site is preferred?

Accepted Answer

Heel (plantar surface)

Answer

The plantar surface of the heel is the recommended site for infant capillary blood collection to avoid injuring bones and nerves in the fingers.

Question 4

Which staining method is used to visualize the presence of acid-fast organisms such as Mycobacterium tuberculosis?

Accepted Answer

Ziehl-Neelsen stain

Answer

The Ziehl-Neelsen (acid-fast) stain uses carbol fuchsin that binds to mycolic acid in the cell walls of acid-fast bacteria like Mycobacterium tuberculosis.

Question 5

A complete blood count (CBC) result shows an elevated WBC with a left shift. This MOST likely indicates:

Accepted Answer

Bacterial infection with increased immature neutrophils

Answer

A left shift means increased bands (immature neutrophils) are released into circulation, which is a classic response to acute bacterial infection.

CCMA - Certified Clinical Medical Assistant Practice Test

CCMA - Certified Clinical Medical Assistant Practice Test

CCMA Laboratory Procedures 4