Cutaneous infection due to Mycobacterium immunogenum: an European case report and review of the literature

Abstract

(no more than 200 words): In the last few years, the incidence of cutaneous infections caused by nontuberculous mycobacteria is increasing. Since Mycobacterium immunogenum was first described in 2001, few case reports have been described, all of them in the American continent. We report a case with cutaneous infection caused by this newly discovered NTB in Europe.A 65-year-old woman presented with a 3-months history of pruritic lesions on abdomen. Examination revealed erythematous inflammatory papules, pustules, and crusts. Three weeks later, mycobacteria were cultured from the biopsy specimen. Mycobacterium immunogenum was identified based on susceptibility test results and polymerase chain reaction (PCR) restriction enzyme analysis. Treatment with clarithromycin was started. M. immunogenum is a nontuberculous mycobacterium that was first described by Wilson et al. in 2001 as a rapidly growing variety and new species in the Mycobacterium chelonae-Mycobacterium abscessus group. PCR-restriction analysis of a 439-bp segment of the hsp65 gene and/or sequencing the species-specific region of the 16S rDNA can confirm this new species. Since the description of M. immunogenum, 8 clinical case reports have been published, most involving cutaneous infections and all of them in the American continent. We present a case of cutaneous infection caused by M. immunogenum in a Spanish woman.