Antibiotics and resistance in dermatology: focus on treating the elderly.

Although elderly patients are at an increased risk for skin infections, the chief culprits are no different than in younger patients. However, many of these organisms have developed resistance to antibiotics. Resistance increases the morbidity, mortality, and cost of treating infections. The mechanisms by which resistance occurs include efflux of antibiotic through a cellular pump, inactivation of the antibiotic by enzymes, or changes in the target affinity for the antibiotic. For dermatologic conditions in the elderly, documented resistance is seen in staphylococci, streptococci, and enterococci. Clinicians can reduce the development of resistance by following infection control and antibiotic use guidelines. To optimize the antibiotic effect and minimize adverse effects in the elderly, pharmacokinetic changes seen with aging should guide antibiotic choice and dosing.