Skin, Soft Tissue Infection Flashcards
What percentage of cat bites become infected compared to dog bites?
80% vs 5%
What is the most common infectious agent in cat bites? Dog bites?
Cat: Pastuerella multicoda
Dog: Pasteurella canis
What is empiric treatment for dog or cat bites?
Amoxicillin-Clavulanate
What are the most common infectious organisms in a human bite? (7)
- Viridins strep 100%
- Bacteroides 82%
- Staph epidermidis 53%
- Corynebacterium 41%
- Staph aureus 29%
- Peptostreptococcus 26%
- Eikenella 15%
What are two vaccine-able disease that always need to be considered with animal bites?
- Tetanus
- Rabies
What are the conditions when a bite would be treated for tetanus?
- Vaccine: minor wound and no vaccine in last 10 years or major wound and no vaccine in last 5 years
- Tetanus Ig: major wound and has not had at least 3 vaccine doses
What is the treatment plan if an animal bite might have passed on rabies?
- Rabies Ig around the wound
- Rabies vaccine at day 0, 3, 7 and 14
What organism causes Cat Scratch Disease?
Bartonella henselae
What is the typical and atypical presentations of Cat Scratch Disease?
Typical: Local lymphadenitis +/- cutaneous lesions several days after exposure that can last 1-3 weeks
Atypical (10%): liver, spleen, ocular, neurological or MSK involvement, fever of unknown origin
What tests are typically used to diagnose Cat Scratch Disease? What would you treat it with?
- Serology (IFA), blood culture, tissue PCR
- Treatment: Azithromycin
What presents as these two classic syndromes:
- triad of tenosynovitis, polyarthritis, dermatitis
- purulent arthritis
Disseminated Gonococcal Infection
What is not common in Disseminated Gonococcal infection?
Urethritis/Cervicitis (but swabs often +ve)
What treatment is used for disseminated gonococcal infection?
Ceftriaxone + Doxycycline x 7 days
Don’t forget to Tx partners!
What is the most common cause of septic arthritis?
Hematological spread > trauma/bite > post-surgery > direct spread from osteomyelitis
What is the most common organism that causes septic arthritis?
Staph aureus
What is the treatment for septic arthritis?
- IV antibiotics based on Gram stain x 4 weeks making sure to cover Staph
- Joint aspiration in all cases, surgical drainage in hip or prosthetic infection
What is Ludwig’s Angina?
Cellulitis of the submandibular/sublingual spaces
What does Ludwig’s Angina almost always result from?
- Oral infection of 2nd or 3rd molars
- 80% of patients report tooth pain or recent dental work
How do you manage Ludwig’s Angina?
- Manage and protect airway (1/3 of cases require intubation)
- IV antibiotics based on organism
- Surgical evalualtion
- CT scan to evaluate abscess and extent of spread
What are the two most common causes of impetigo?
- S. aureus
- Group A strep
What are the two types of impetigo and their most obvious clinical feature?
Bullous (vesicles) and non-bullous (golden crust)
What are some risk factors for having a diabetic foot infection? (7)
- Previous amputation
- Wound extending to bone
- Peripheral vascular disease
- Ulcer duration >30days
- Loss of sensation
- History of recurrent ulcers
- Wound caused by trauma