Acute Rheumatic Fever with Erythema Marginatum - Painless, nonpruritic, red annular macules appeared on the upper limbs and abdomen (Panel A shows the right forearm; black ink dots indicate the diameter of one lesion 10 hours before the time that the photograph was taken). Skin biopsy revealed perivascular infiltration of lymphocytes and neutrophils in the dermis (Panel B, hematoxylin and eosin). #Clinical #Derm #Pathology #Erythema #Marginatum #ErythemaMarginatum #Microscopy #NEJM