Infectious Disease

Question 1

The only antibiotic that covers MRSA, but not Strep

Answer 1

Bactrim

Question 2

Oral antibiotics for MRSA

Answer 2

1. Clindamycin

2. Bactrim

3. Doxycycline

You should use doxy or clinda empirically, since they also cover strep (which can mimic staph). To decide whether to use clinda or doxy, you should refer to your institutional antibiogram.

Question 3

Organisms that may carry AmpC

Answer 3

MY SPACE

• Morganella
• Yersinia
• Serratia
• Proteus (non-mirabilis) or Provindentia
• Acinetobacter
• Citrobacter
• Enterobacter

Question 4

How is AmpC induction going to present clinically?

How should you treat it?

Answer 4

Presentation: Patient will have an infection with one of the MYSPACE organisms. They will be ceftriaxone S, cefotaxime R on sensitivites.

You will probably treat with ceftriaxone, and they will get better for 24 hours, but then start to get worse again. CT will be negative for abscess.

What should you do: Treat with zoasyn or meropenem instead. Cefepime has also been shown to work, but since it is also beta lactam some clinicians are hesitant.

Question 5

Empiric coverage for febrile neutropenia in high risk patients

Answer 5

Cefepime monotherapy is often okay. Otherwise other antipseudomonal monotherapies (piperacillin-tazobactam, meropenem).

Vancomycin can be added if MRSA is a concern

If fever persists 72 hours, send fungal markers and start empiric antifungals.

Question 6

How to tell a leukemoid reaction from leukemia

Answer 6

Leukemoid reactions will have:

1. Some form of infectious trigger
2. A proportionate increase in all myeloid lineages
3. Elevated leukocyte alkaline phosphatase (High in leukemoid rxn, low in CML)