Chapter 32 - Hand Infections Flashcards
(98 cards)
What are the most common bacteria found in hand infections?
Staph. aureus (50-80%) and Beta-hemolytic streptococci; >50% are polymicrobial
What is the basic treatment principle when dealing with infections in the hand?
DICE: Drainage and Debridement, Immobilization, Chemotherapy (antibiotics), Elevation
What is the most common site for infection (tissue of the hand)?
Dorsal subcutaneous tissue, followed by tendon, joint, bone and subfascia
What is the most common mechanism of hand infections?
Trauma (penetrating injuries or bites)
How do superficial hand infections tend to be treated?
Antibiotics (14-21 days), splinting (depending on severity)
How to deep hand infections tend to be treated?
Surgical irrigation and debridement, antibiotics, splinting
What patient risk factors predispose them to hand infections?
Immunocompromised states, IV drug use, DM, steroid use, microvascular disease and damaged blood supply (trauma). Infections tend to be virulent.
Whats are the common pathogens found in diabetic patients?
Gram negative and polymicrobial, subepidermal abscesses are unique to this population.
How do you treat a herpetic whitlow in an immunocompromised patient
Antivirals (will not resolve spontaneously)
What characterizes cellulitis of the hand?
Erythema, swelling, tenderness, associated lymphangiitis may indicate a more severe infection
What bacteria is most often seen with cellulitis?
Group A Beta-hemolytic streptococcus - S. Aureus may also be seen
What are the oral antibiotics of choice in cellulitis?
Nafcillin, dicloxacillin, and cephalexin; erythromycin if pen allergic
What are the most commonly isolated pathogen in human-bite infections?
alpha-hemolytic strep and s. aureus
What is the most commonly involved area in human bites
MCP joint (“fight bites”)
Where is the most common topography for occurence of hand infections?
Flexor tendon zone II
What organism is commonly isolated in one-third of human bite wounds?
Eikenella corrodens, 7-29%, must be cultured in 10% CO2, destroys articular cartilage quickly
What is the recommended treatment for human bite injury?
Surgical extension and debridement with arthrotomy, culture, antibiotics, leave the wound open
What organism commonly infects animal bites and scratch wounds?
Pasturella multilocida
What is necessary for diagnosis and treatment of an animal bite?
Xray (to assess bone and foreign objects such as teeth), antibiotics (augmentin or IV unasyn), irrigation
What are the common cultures requested in hand infections?
Aerobic, anaerobic, cultures in Lowenstein-Jensen medium for atypical mycobacterium
What are the common stains needed in hand infections?
Gram stain, Ziehl-Neelsen (mycobacterium), Tzanck smear (herpes)
When evaluating a hand infection and a fungus is suspected, what preparation is necessary?
KOH (potassium hydroxide)
What is the most common infection in the hand of HIV patients?
Herpes simplex
When using aminogylcoside (eg gentamicin), for gram negative coverage, what are potential side effects?
Nephrotoxicity and ototoxicity