Infection in the upper body: hand and burn-wound microbiology and considerations for antimicrobial therapy

Gram-positive bacteria are the predominant organisms in hand infection and in burn wounds of the upper extremities. In a recent study of isolates from patients who were treated at our institution, Staphylococcus aureus and beta-hemolytic Streptococcus group A organisms were the most common organisms in infection of the hand; they were found in 36.3% and 14.4% of cases, respectively. The most common organisms in burn wounds were Enterococcus species, S. aureus, and Escherichia coli, which were found in 21.2%, 20.5%, and 16.7% of patients, respectively. Between 1969 and 1989, the prevalence of Pseudomonas species in burns decreased markedly, whereas that of S. aureus remained relatively stable and that of Enterococcus increased substantially. Over this period, both enterococci and coagulase-negative staphylococci emerged as troublesome pathogens in patients with burns. Methicillin-resistant S. aureus, which was first seen in our institution in 1981, continues to be found in a small proportion of patients. We have achieved successful results in certain surgical settings with the use of gentamicin-dispersing polymethyl-methacrylate beads to provide sufficient antimicrobial concentrations in poorly vascularized or avascular tissue. Additional topical antimicrobials that are potent against gram-positive bacteria are needed.