OnlineMedEd: Infectious Disease - "Skin Infections" Flashcards
Cellulitis is usually caused by _______________.
Streptococcus (spreading) or Staphylococcus (abscess)
Cellulitis is described as _______________.
warm, tender, and well-demarcated
Why don’t you culture cellulitis?
Skin has commensal bacteria and will come back falsely positive.
Review the drugs used to treat Step. and Staph. STIs.
•Strep:
- Nontoxic: cephalexin or cefazolin
- Toxic: Unasyn or Zosyn
•Staph:
- Nontoxic: Bactrim or clindamycin
- Toxic: vancomycin, clindamycin, linezolid
Consider osteomyelitis in someone who ________________.
has wounds that expose bone or those with recurrent cellulitis
X-rays are typically only positive in cases of osteomyelitis ________________.
after two weeks
The best test is MRI.
The best test for osteomyelitis is ____________.
biopsy
How do you treat osteomyelitis?
- Debridement of the necrotic bone
- 4-6 weeks of antibiotics (often vancomycin or Zosyn)
- F/U with CRPs and ESR
Gas gangrene generally presents after what kind of wound?
Penetrating, dirty wound
Diagnose gas gangrene by ______________.
feeling for crepitus and then x-ray
What drugs are indicated for gas gangrene?
Penicillin and clindamycin
Necrotizing fasciitis on the perineum is called _____________.
Fournier’s gangrene
Describe the clinical presentation of necrotizing fasciitis.
- Pain out of proportion to exam
- Rapidly spreading erythema
- Blue-gray discoloration
- Toxic
Describe how NF is treated in real life and on the test.
•Real life:
- Vancomycin
- Zosyn
• Test:
- 3rd generation cephalosporin
- Clindamycin
- Ampicillin
What organisms most often cause osteomyelitis?
In all cases, Staphylococcus is the most likely. However, in these cases the second-most likely organism is unique:
- SIckle cell: Salmonella
- Diabetic: polymicrobial
- Puncture wound: Pseudomonas
- Cirrhotic person eating oysters: Vibrio foliferous
- Gardener: Sporothrix fungi
