A Case of Lepromatous Leprosy in an Elderly Patient

Leprosy is an infectious disease caused by Mycobacterium leprae. Patients usually present with hypopigmented or erythematous plaques with central hypoesthesia or tenderness, and necessitate a differential diagnosis with eczema, granuloma annulare, sarcoidosis, syphilid, mycosis fungoides, erythema nodosum, and skin cancer. A 93-year-old woman presented with asymptomatic erythematous plaques and subdermal nodules on the face and extremities for 6~ 7 months, and the lesions were suspicious for skin cancer. Histopathologic examination revealed diffuse infiltration of foamy histiocytes separated by a grenz zone. Acid-fast bacilli were seen in Ziehl - Neelsen stain with clumps called globi. Based on clinical and histopathological findings, she was finally diagnosed with lepromatous leprosy. The patient was diagnosed with leprosy at an advanced age; thus, we report the case in which dermatologists should consider leprosy as well as skin cancer in the elderly patients with unusual erythematous nodules, despite decreasing prevalence of leprosy.