Microbiology

Question 1

What kind of pneumonia is caused by Chlamoydophila pneumoniea?
• Presentation?
• Diagnosis (key facts)?

Answer 1

Atypical Pneumonia presents as low grade fever, and a dry hacking cough, with sore throat and headaches and may onset over a week or so. (transmitted via aerosol) Diagnosis:
• Cytoplasmic Inclusions (small dots)
• Giemsa or fluorescent staining (lacks peptidoglycan cell wall so much use Giemsa)

Question 2

What is the Reservior for Borrelia burgdorferi?

Answer 2

White footed mouse

Remember with lyme FACE:
• Facial Nerve Palsy (often bilateral) (stage 2)
• Arthritis (stage 3)
• Cardiac Block (AV block) (stage 2)
• Erythema migrans (stage 1)

Question 3

What are some infectious agents that cause rash on the palms of the hands and soles of the feet?

Answer 3

• Rocky Moutain Spotted Fever - papable purpura vasculitis
• Coxsackie Virus
• Secondary Syphillis - Treponema pallidum (more closely resembles RMSF)

Question 4

What cancer is thought to be caused by Schistosoma?
• where is it found?
• What disease does it cause?

Answer 4

Bladder Carcinoma

Found in Snails and causes granulomas, fibrosis, and hepatic and spleen inflammation

Treated with Praziquantel

Question 5

Echinococcus granulosus
• What is it?
• Transmission
• Disease caused?
• Treatement?

Answer 5

Tapeworm transimitted by ingestion of eggs from dog feces (sheep, wallabies, kangaroos, may carry this too)

Disease
• Cysts in the Liver (injected with ethanol before removal)
• Anaphylaxis can be caused if antigens are released

Treatment
• Albendazole

Question 6

Schistosoma
• Structure
• Transmission
• Presentation
• Treatment

Answer 6

Structure:
• Protozoan (S. mansoni and S. haeatobium)

Transmission:
• HOST: Snails
• Cercariae penetrate the skin of humans to gain access

Presentation:
• Liver and and Spleen enlargment with fibrosis and inflammation
• Chronic infection can lead to Squamous Cell Carcinoma of the bladder

Treatment:
• Praziquantel

Question 7

A patient is exposed to parrots and is treated with a long 3 week course of doxycycline after developing high fever, malaise, and nonproductive cough.

• what disease did he likely have?
• What would histology show?

Answer 7

Disease: Psittacosis
Organism: Chlamydophila psittaci

Histology:
- Will show an obligate intracellular organism with a cell wall

Question 8

What do you see when you stain Pneumocytis jirovecii with silver stain?

Answer 8

Flying saucer-shaped/flying saucer shaped parasites