Infectious Diseases

Question 1

In splenectomy pts, which encapsulated organisms are we worried about? (7)

Answer 1

Cryptococcus neoforms
Klebsiella pneumonia 
Salmonella typhi
Streptococcus pneumonia
Hemophilus influenza
Neissera meningitis 
Pseudemonas aerginosa

Question 2

In HIV patients, which infections are we worried about when CD4 counts are 200, 100, 50?

Answer 2

200: cryptococcosis, PJP
100: toxoplasmosis
50 - MAC, CMV

Question 3

What is the classic triad for malaria?

Answer 3

Onset 8-25 days post bite.

Fever
Anemia
Splenomegaly

Can also have N/V/D, malaise, myalgias, vague abdominal pain.

Question 4

What is the investigation for malaria?

Answer 4

Thick/thin malaria smear
Need 3 negative to r/o
~75-90% sensitive

Thick smear to identify parasite, thin smear to determine species (Falciparum vs. non-falcipcarum)

Question 5

What is the geographical distribution of malaria?

Answer 5

Broad brand at the level of the Equator

Question 6

Why should you avoid NSAIDs in Dengue fever?

Answer 6

Because of the viruses tendency to cause hemorrages and NSAIDs can make that worse. Give tylenol if analgesics needed

Question 7

What organism causes typhoid fever?

Answer 7

Salmonella typhi/paratyphi

Question 8

Classic >10 days fever, relative bradycardia, splenomegaly and rose spots across chest. What is the dx?

Answer 8

Typhoid fever

Question 9

What are the 3 stages of illness in Lyme disease?

Answer 9

1) Erythema chronicum migrans (growing lesion)
- 7 days after bite
- Red macule or papule at the site
- Gradually expands to 15cm
- Raised outer boarder with central clearing (Bull’s eye)
- Can be multiple if more than one bite
- Non-tender, non-pruritic
- Constitutional symptoms
- Self resolving over one month
2) Neuro/Cardiac
- Hematogenous dissemination
- 1 month after bite
- 7% Bells’ palsy – bilateral is pathognomonic
- Heart block or pancarditis
3) Arthritis
- Weeks to years later
- Knee>other large joints>TMG>fingers and toes
- Serology is unreliably sensitive, so clinical course is helpful

Question 10

What are the 2 types of Nec Fas?

Answer 10

1. Type I (polymicrobial – typically Bacteroides, Clostridium or Peptostreptococcus along with facultative anaerobc streptococci or Enterobacteriaceae)
2. Type II (Group A strep or other monomicrobial causes such as H. influenzae)

Question 11

What anti-biotics do you start with presumed Nec Fascitis? (in addition to calling sx)

Answer 11

Meropenem + Clindamycin + Vancomycin

Question 12

What are the airborn (<5 microns) pathogens? (name 3)

Answer 12

TB
Measles
Varicella/ Disseminated Shingles (need contact also).

Question 13

What are common organisms req droplet isolation?

Answer 13

Mumps
H. influenza
Mycoplasma pneumonia
Pertussis
Respiratory viruses (e.g., influenza, parainfluenza virus, adenovirus, respiratory syncytial virus, human metapneumovirus)
Bordetella pertusis
For first 24 hours of therapy: Neisseria meningitides, group A streptococcus