Ecthyma

Ecthyma is a cutaneous infection due to Streptococcus pyogenes and Staphylococcus aureus that involves epidermis and deep dermis. It follows trauma or scratching due to arthropod bites. Bacterial infections, including ecthyma, are a frequent reason for dermatologic consultation in travelers returning from tropical or subtropical countries. Ecthyma begins as a vesicle or pustule that progresses to a 2–3 cm ulcer with necrotic base, and yellow–green crust accompanied with purulent discharge. Ulcers may be single or multiple and usually involve the lower extremities. Differential diagnosis (in travelers) includes leishmaniasis and rickettsial infections. Diagnosis (of ecthyma) can be established in the setting of characteristic skin disease and confirmed with bacterial culture. Treatment consists of systemic antibiotics coupled with wound care, followed by complete resolution in most cases.