Acute pyogenic infections of the skin, caused by hemolytic streptococci and S. aureus, account for the vast majority of bacterial infections of the skin seen in ambulatory practice. In preschool children the principal manifestation is pyoderma, which is usually caused by Group A Streptococcus. In this age group pyoderma regularly responds to systemic penicillin therapy plus adjunctive local care to the lesions. However, in older age groups, the ability to distinguish streptococcal from staphylococcal skin infections on the basis of clinical features alone is poor, and penicillin treatment failures are more common. Safe, effective antibiotics that are effective against both staphylococci and streptococci are readily available. For this reason penicillinase-resistant semisynthtic penicillins and or erythromycin can be used to treat acute pyogenic skin infections in older age groups.
