Hand-Foot-Mouth Disease Mimicking Erythema Multiforme in an Immunocompetent Adult.

Corresponding Author Hyun Jeong Park Department of Dermatology, Yeouido St. Mary's Hospital, College of Medicine, The Catholic University of Korea, 10 63-ro, Yeongdeungpo-gu, Seoul 07345, Korea Tel: +82-2-3779-1230, Fax: +82-2-783-7604, E-mail: hjpark@catholic.ac.kr https://orcid.org/0000-0002-0138-9885 Dear Editor: Hand-foot-mouth disease (HFMD) is a infection caused by Enterovirus and Coxsackievirus that predominantly affects children and symptoms include an erythematous maculopapular or vesicular eruption localized on palms, soles, and perioral skin. Immunocompetent adults recently showed an atypical erythema multiforme (EM)-like eruption. EM is characterized by annular eruption caused by a hypersensitivity reaction from infections such as herpes simplex and mycoplasma pneumonia. Also, unusual viral pathogens Coxsackievirus A6 or A10 have been reported with HFMD, leading to more severe disease course. A 38-year-old male was presented with a pruritic, erythematous maculopapular targetoid eruption on both hands, feet, and trunk for one week (Fig. 1). Initially, he experienced malaise and mild fever before the skin eruption, which did not involve oral mucosa. Blood chemistry tests, rapid plasma reagin, human immunodeficiency virus, and hepatitis serology were normal. Histopathological examination of a macule on his left arm showed neutrophils presented with focal necrosis in upper epidermis and vacuolar alteration in the dermoepidermal junction (Fig. 2). Initially, the patient was misdiagnosed with EM due to clinical exam findings of targetoid lesions. But the additional laboratory examination showed all positive titers of A B