Necrotizing fasciitis involving Gram + cocci in clusters or tetrads

- diagnosis and order of management of various strains

1. Staphylococcus aureus esp MRSA

    - treat as if MRSA w/ vancomycin, linzolid, and/or daptomycin

2. Methicillin sensitive S. aureus

   - treat w/ nafcillin, oxacillin, 1G cephalosporin, clindamycin

Necrotizing fasciitis with Gram + cocci in chains

- diagnosis and management

Suspect Streptococci pyogenes

Treat with penicillin G, early cephalosporin, or clindamycin

Necrotizing fasciitis treated for Strep or S. aureus but no improvement

- diagnosis and management

Differential diagnoses

- inadequate debridment

- improper Gram stain review

- additional organisms

- mixed infections

Management

- ribosomal protein inhibitors to stop toxin production

   ~clindamycin

   ~ linezolid

Necrotizing fasciitis caused by mixed infection involving Gram +/- rods and cocci

- management

1. Suspect mixed flora w/ anaerobes

2. Empirical therapy

 - β-lactam/β-lactamase inhibitor

     ~amp/sulbactam

     ~pip/tazobactam

 - carbapenem

     ~imi-, mero-, or doripenem

     ~ertapenem

 - advanced cephalosporin or quinolone  + metronidazole or clindamycin

3. Adjust antibiotics after culture results

Burn Wound Organisms

- Gram (+) organisms

- Gram (-) organisms

- Fungi

- Viruses

Gram (+) organisms

- S. aureus

- S. epidermidis

- Enterococcus (inc. VRE)

Gram (-) organisms

- Pseudomonas

- Enterobacteriaceae

- Acinetobacter baumanii

- Bacteroides spp

Fungi

- Candida

- Aspergillus

- Fusarium

- Alternaria

- Zygomycetes

Viruses

- HSV

- VZV

- CMV

Burn wound antibiotic treatment

- Pseudomonas aeruginosa

- Staphylococcus aureus (MRSA, MSSA)

Pseudomonas aeruginosa

- anti-Pseudomonal β-lactam

   ~pip/tazo

   ~ceftazidime

   ~cefimpe

   ~carbapenem

- aminoglycosides

- fluoroquinolones

- colistin

MRSA

- vancomycin

- linezolid

- daptomycin

MSSA

- nafcillin or oxacillin

- cephalosporin

Vascular access site infection management for S. aureus or epidermidis

- considerations

- therapy

- MSSA or MSSE?

- Treatment time course if device removed? Not removed?

Considerations

1. remove device if patient very ill

2. remove device if severe local infection

3. consider echocardiogram for endocarditis

Treatment for:

MRSA

- daptomycin, vancomycin

MSSA or MSSE

- oxacillin or nafcillin

- cephalosporin

Tx time course if deviced removed

- 2 weeks

Tx time course if deviced remains

- 4 weeks w/ blood cultures @ 5 weeks

Vascular access site infection by yeast

- Tx for sick patient

- Tx for mildly-moderately ill patient

Sick patient

- capsofungin

- voriconazole

- amphotericin B

- REMOVE VASCULAR DEVICE!!

Mild/Moderately sick patient

- fluconazole

- REMOVE VASCULAR DEVICE!!

Fever of unkown origin in renal transplant patient

- organisms

CMV

- few or no focal Sx

- abnormal liver enzymes

- Rx

   ~ganciclovir or valganciclovir

TB

Fungi

- Cryptococcus (esp w/ CNS Sx - meningitis)

    ~initial Tx = ampB + flucytosine until response

    ~ maitenance = fluconazole 200-400 mg/d until culture and cryptococcal Ag are negative

- Coccidioides

- Histoplasma

Multiple myeloma common pathogens

- pathogens and treatment

Encapsulated bacteria esp:

- Streptococcus pneumoniae

   ~ Tx:

       - high dose PCN

       - advanced cephalosporin (ceftriaxone, cefotaxime, cefempime)

       - quinolone (levo- & moxifloxacin)

       - vancomycin

- Haemophilus influenzae

  ~ Tx:

      - ceftriaxone

      - β-lactam/β-lactamase inhibitor (amp/sul or pip/tazo)

      - carbapenem (ertapenem)

      - quinolone

      - TMP/SMX

      - IV Ig ?

Chronic granulomatous disease pathogens

- pathogens

Pathogens = catalase (+) organisms

- S. aureus

- Enterobacteriaceae

- Aspergillus spp

Severe infections:

-Streptococcus pneumoniae

-Haemophilus influenzae

-Neisseria meningitidis

-Babesia microti

-Ehrlichia

-Bartonella bacilliformis

-Capnocytophaga canimorsis

Osteomyelitis in sickle cell anemic patients:

- most common etiological pathogens

- best way to get diagnosis of organism

Organisms:

Salmonella (70%)

Staphylococcus aureus (10%)

Other Gram (-) rods (7%)

Diagnosis:

- blood culture + bone culture

- pus culture from fistula is uncertain