Certified Phlebotomy Technician Exam Special Specimen Collections 4 — Questions and Answers
Question 1: A sputum specimen for culture and sensitivity should ideally be collected at what time of day?
- After the evening meal
- First thing in the morning upon waking (Correct answer)
- Midafternoon when secretions are thinnest
- After vigorous physical activity
Correct answer: First thing in the morning upon waking
Early morning sputum is preferred because secretions accumulate overnight and yields the highest concentration of organisms for accurate culture results.
Question 2: Which of the following describes the correct handling of a specimen collected for cryoglobulin analysis?
- Refrigerate immediately at 4°C
- Keep warm at 37°C from collection through centrifugation (Correct answer)
- Freeze immediately at -20°C
- Process at room temperature like a standard SST
Correct answer: Keep warm at 37°C from collection through centrifugation
Cryoglobulins precipitate at cold temperatures, so the specimen must be kept at 37°C until centrifugation to prevent false-negative results from protein loss.
Question 3: When collecting a specimen for erythrocyte sedimentation rate (ESR), which tube is used and what is the maximum time before testing?
- SST; must test within 4 hours
- EDTA (lavender-top); must test within 4 hours of collection (Correct answer)
- Sodium citrate (blue-top); must test within 2 hours
- Heparin (green-top); must test within 1 hour
Correct answer: EDTA (lavender-top); must test within 4 hours of collection
ESR is performed on EDTA whole blood and must be tested within 4 hours of collection (or 12 hours if refrigerated at 4°C) to yield valid results.
Question 4: What is the minimum volume of each blood culture bottle (aerobic and anaerobic) typically required for an adult collection?
- 1–2 mL per bottle
- 8–10 mL per bottle (Correct answer)
- 15–20 mL per bottle
- 3–5 mL per bottle
Correct answer: 8–10 mL per bottle
Standard adult blood culture protocols require 8–10 mL per bottle to maximize pathogen detection sensitivity.
Question 5: A timed specimen for cortisol is ordered at 8 AM and 4 PM. Why is timing critical for this test?
- Cortisol is unstable and degrades within 2 hours
- Cortisol follows a diurnal rhythm with peak levels in the morning and nadir in the evening (Correct answer)
- The laboratory can only run cortisol assays at specific times
- Cortisol must be drawn fasting and the patient may eat at noon
Correct answer: Cortisol follows a diurnal rhythm with peak levels in the morning and nadir in the evening
Cortisol levels follow a circadian pattern, peaking in the early morning and reaching their lowest point in the evening; timed draws allow evaluation of this normal variation.
Question 6: Which of the following is correct regarding throat swab collection for strep culture?
- Swab only the anterior tongue and hard palate
- Swab both tonsillar pillars and the posterior pharynx while avoiding the tongue and uvula (Correct answer)
- Insert the swab into the nostril rather than the throat
- Collect after the patient has gargled with antiseptic mouthwash
Correct answer: Swab both tonsillar pillars and the posterior pharynx while avoiding the tongue and uvula
For throat cultures, the swab must contact both tonsillar pillars and the posterior pharynx — the primary sites of streptococcal colonization — while avoiding the tongue and uvula.
Question 7: During an oral glucose tolerance test (OGTT), which of the following actions by the patient would invalidate the test?
- Drinking required water between draws
- Sitting quietly in the waiting room
- Smoking a cigarette during the test (Correct answer)
- Having the blood drawn 5 minutes late
Correct answer: Smoking a cigarette during the test
Smoking during an OGTT stimulates catecholamine release, which raises blood glucose and can falsely elevate results.
Certified Phlebotomy Technician Exam Special Specimen Collections 4
A sputum specimen for culture and sensitivity should ideally be collected at what time of day?