19. RTI 7

Question 1

A 6 y/o boy presents with a cough beginning 2 weeks ago. He is now c/o abd cramping pain, diarrhea, weakness, and hematuria. Labs show elevated ALT and AST. His mother reports that he has been too tired to play outside the last few weeks. He particularly loves catching frogs in their neighborhood pond. A sputum sample is taken and cultured. Which of the following is a characteristic of the infectious agent?

A. Biphasic life cycle
B. Acid Fast Bacilli
C. Cold serum agglutination 
D. Cultured on Buffered Charcoal Yeast Extract
E. MacConkey Agar

SZ

Answer 1

Ans. D. Cultured on Buffered Charcoal Yeast Extract

The boy often plays in water, Legionella.

Biphasic life cycle- chlamydophila pneumoniae
Acid Fast Bacilli- M. tuberculosis
Cold serum agglutination - Mycoplasma pneumoniae
MacConkey Agar- Klebsiella

Question 2

A HIV positive 45 y/o male presents with chronic cough with bloody sputum for 5 wks. He has lost a great deal of weight, c/o night sweats, mild fever and fatigue. Which of the following is not a growth media/stain for culturing the bacteria?

A. Lowenstein-Jensen Agar
B. Ziehl-Neelsen Stain
C. Oleic Acid-albumin broth
D. Rhodamine-Auramine Fluorescent Stain
E. Methylamine Silver Stain 

SZ

Answer 2

Ans. E. Methylamine Silver Stain is for Legionella

The patient has Mycobacterium tuberculosis

Question 3

A 20 year old military recruit is having his a complete physical done during in processing. During this exam he has a PPD test done which is read as 7.7 mm what patient populations does this patient fall under?

A. Individuals with HIV infection 
B. Organ Transplant recipients 
C. No know risk factors of tuberculosis 
D. Prior untreated tuberculosis 
E. Recent Immigrant from tuberculosis-endemic country 

RFA

Answer 3

ANS. E Recent Immigrants from tuberculosis-endemic country- PDD test >= 10mm

A. B and D- PDD test >= 5mm

C. PDD test>=15mm

Question 4

A 49 year old plummer comes to the doctor with symptoms that are consistent with pneumonia. Culture is done showing a gram negative motile non spore forming rod. What culture medium does this organism thrive on?

A.Lowenstein-Jensen Agar
B. Loeffler Coagulated Serum 
C. Chocolate Agar
D.Buffered Charcoal yeast 
E. Oleic Acid- Albumin broth 

RFA

Answer 4

Ans. D -The culture and history indicate Legionella which grows on Buffered Charcoal yeast.

A & E- Mycobacterium Tuberculosis

B. Corynebacterium diphtheriae

C. H. Infuenzae