Microbiology – 03

Author: Nancy Ciau, M.D. & Barbara Haller, M.D.

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1. The parasite egg in image 1 was identified. What parasite has a high incidence of being found in association with the one in the image?

Microbiology - Part 3, Image #1
Microbiology - Part 3, Image #1
2. Mycobacterium szulgai has an interesting characteristic. The organism is a _____ @ 25°C and a _____ @ 37°C.
3. What obvious morphologic characteristic distinguishes Bacillus anthracis from Bacillus cereus?
4. You get a call from a clinician who insists on ordering a “Legionella pneumophila antigen” on a urine specimen because the team highly suspects this organism, has already started the patient on treatment, and would like to rapidly confirm their clinical diagnosis; however, you find out that no other microbiology test was ordered. What do you tell the clinician?
5. The organism present on this older blood agar plate (image 3) was cultured from the CSF of an elderly man who had meningitis. Which of the following is NOT seen with this organism?

Microbiology - Part 3, Image #3
Microbiology - Part 3, Image #3


Microbiology - Part 3, Image #3
Microbiology - Part 3, Image #3


Microbiology - Part 3, Image #3
Microbiology - Part 3, Image #3
6. The organism seen in image 5 is that of mycobacterium growing on a plate. Which of following mycobacteria show this morphology?

Microbiology - Part 3, Image #5
Microbiology - Part 3, Image #5
7. The organism in image 2 (Sabouraud dextrose plate) was cultured from lung tissue obtained from an organ transplant patient. What is the organism?

Microbiology - Part 3, Image #1
Microbiology - Part 3, Image #2
8. See image 6 of a peripheral blood smear. You obtain the history that this patient lives on the Northeast Coast with her family, and none of them have strayed far from that area. She recently developed fever, malaise, anorexia, and fatigue. What is the most likely diagnosis?

Microbiology - Part 3, Image #6
Microbiology - Part 3, Image #6
9. Which of the following viruses are non-enveloped?
10. Image 4 is that of a test used to presumptively identify a catalase-negative streptococcus with characteristic hemolysis. Which organism is streaked perpendicular (identified by arrow) to the presumptive organism (presumptive - the unknown organism being tested)?

Microbiology - Part 3, Image #4
Microbiology - Part 3, Image #4