Bacteremia and ecthyma caused by Streptococcus pyogenes in a patient with acquired immunodeficiency syndrome.

Ecthyma is an ulcerated form of impetigo due to Streptococcus pyogenes, seen primarily in children with poor hygiene. The authors report a homosexual man with acquired immunodeficiency syndrome (AIDS) who developed severe ecthyma and bacteremia caused by S. pyogenes. Opsonizing antibody to the M protein of S. pyogenes is important in immunity to this organism. Patients with AIDS may have defective humoral immunity as well as defective cellular immunity, and such a defect may have rendered this patient abnormally susceptible to severe infection with S. pyogenes.