Impetigo is the most common skin infection seen in neonates, with impetiginous infection of atopic dermatitis being the second most common. Caused by Staphylococcus aureus or Group A streptococcus (Streptococcus pyogenes), it is localized to the subcorneal portion of the epidermis. It has been suggested but not proven that males develop impetigo more so in the diaper area and lower abdomen while females may have it on the face more often. Constitutional symptoms and fever are minimal. Minor trauma such as insect bites or abrasions can predispose to infection.

Although methicillin-resistant S. aureus (MRSA) infection of the skin usually presents as recurrent furunculosis or skin abscesses, MRSA has been shown to cause impetigo. Culture and sensitivities should always be performed in patients with lesions suspicious for cutaneous infection, and empiric coverage for MRSA should be instituted if clinical suspicion is high.