CMT Laboratory Procedures and Specimen Collection 2

Question 1

The preferred method for collecting a urine specimen for routine urinalysis and culture is:

Accepted Answer

Midstream clean-catch

Answer

A midstream clean-catch specimen minimizes contamination from urethral flora by discarding the initial urine stream before collecting the mid-portion.

Question 2

A 24-hour urine collection should be stored at which condition during the collection period?

Accepted Answer

Refrigerated at 2–8°C or with a specified preservative

Answer

Refrigeration at 2–8°C or use of the appropriate chemical preservative prevents bacterial growth and analyte degradation during the full 24-hour collection period.

Question 3

On a urine dipstick, a positive nitrite result suggests the presence of:

Accepted Answer

Gram-negative bacterial infection

Answer

Many gram-negative bacteria convert urinary nitrates to nitrites via bacterial reductase, making a positive nitrite test an indicator of gram-negative urinary tract infection.

Question 4

When collecting a stool specimen for occult blood testing, the patient should avoid which food for 3 days before collection?

Accepted Answer

Red meat and raw broccoli

Answer

Red meat contains hemoglobin, and certain raw vegetables contain peroxidases, both of which can cause false-positive guaiac-based occult blood tests.

Question 5

Which technique is used to collect a throat culture for Group A Streptococcus?

Accepted Answer

Swab the tonsils and posterior pharynx while avoiding the tongue and teeth

Answer

Group A Strep colonizes the tonsils and posterior pharynx; swabbing there while avoiding contamination from saliva on the tongue and teeth yields the most accurate specimen.

(CMT) Certified Medical Technician Practice Test

(CMT) Certified Medical Technician Practice Test

CMT Laboratory Procedures and Specimen Collection 2