Atopic dermatitis (AD) is the most common skin disease of children and is increasing in prevalence worldwide. Skin infection with Staphylococcus aureus is common especially during exacerbations of AD. Infection with group A streptococcus (GAS) is less frequent but also well documented. Workers in San Francisco (Pediatr Dermatol 2011;28:230–4) have compared the clinical features of the two infections. A retrospective study for the period 1999–2001 revealed 245 skin culture results for children with AD, 187 (76%) positive for S aureus or GAS. Among these 187, 143 (76%) grew S aureus alone, 10 (5%) streptococci alone, of which 9 were GAS, and 34 (14%) both S aureus and streptococci, of which 29 were S aureus and GAS). Patients infected with GAS were more likely to have fever, to have facial and periorbital involvement, and to be admitted to hospital, compared with patients infected with S aureus alone. They were significantly more likely to develop bacteraemia and cellulitis. Peritonitis, psoas abscess and toxic shock syndrome were also seen as complications of GAS infection. A review of skin cultures for 2004–08 revealed 74 children with AD and a culture positive for GAS. Fifty-one (69%) of these children also had S aureus cultured and …