Diagnosis and treatment of impetigo.

Impetigo is a highly contagious, superficial skin infection that most commonly affects children two to five years of age. The two types of impetigo are nonbullous impetigo (i.e., impetigo contagiosa) and bullous impetigo. The diagnosis usually is made clinically, but rarely a culture may be useful. Although impetigo usually heals spontaneously within two weeks without scarring, treatment helps relieve the discomfort, improve cosmetic appearance, and prevent the spread of an organism that may cause other illnesses (e.g., glomerulonephritis). There is no standard treatment for impetigo, and many options are available. The topical antibiotics mupirocin and fusidic acid are effective and may be superior to oral antibiotics. Oral antibiotics should be considered for patients with extensive disease. Oral penicillin V is seldom effective; otherwise there is no clear preference among antistaphylococcal penicillins, amoxicillin/clavulanate, cephalosporins, and macrolides, although resistance rates to erythromycin are rising. Topical disinfectants are not useful in the treatment of impetigo.