Ecthyma. An enlarging, slightly painful lesion which started as a “blister” on the forearm (without any prior history of trauma). Culture grew S pyogenes. Ecthyma is a discrete, round lesion with a dark crust in the center surrounded by a rim of shallow ulceration. (Photo contributor: Andrea Marmor, MD.)

Source: Shah BR, Lucchesi M, Amodio J, Silverberg M. Atlas of Pediatric Emergency Medicine. New York, NY: McGraw-Hill Education; 2013.