Bacterial and atypical mycobacterial infections

DEFINITION/OVERVIEW Erythrasma is a cutaneous bacterial infection caused by Corynebacterium minutissimum, a gram-positive bacillus and part of the normal skin flora. It generally presents as a red, scaly plaque with well demarcated borders involving an intertriginous site (30). Progression of the lesion may cause the borders to advance and the color to change from red to brown with an area of central clearing. Infection by C. minutissimum occurs most commonly in the skin between the toes, in the axillae, inframammary skin folds and, in obese persons, the infrapannicular skin. Infection between the toes remains the most common site of erythrasma where it is often confused with localized fungal infections. The reason for this localization is due to the predilection of the organism for warm moist environments and explains why it is more common in warm, humid climates and in those with hyperhidrosis. Poor hygeine may also contribute to the development of the condition. Fungi also infect similar sites and up to 30% of patients with erythrasma are coinfected with Candida albicans.1.