Disseminated Mycobacterium immunogenum infection presenting with septic shock and skin lesions in a renal transplant recipient.

Mycobacterium immunogenum is a relatively new species within the Mycobacterium chelonae-Mycobacterium abscessus group of rapidly growing mycobacteria (RGM). M. immunogenum was first characterized in 2001 and, similar to other RGM, is an ubiquitous environmental organism. This organism has most commonly been implicated in cutaneous infection in both healthy and immunosuppressed patients. To our knowledge, this is the first reported case of septic shock in the setting of disseminated M. immunogenum infection. Definitive identification of this organism requires gene sequencing at specialized centers, which may limit its detection. M. immunogenum is resistant to many anti-mycobacterial agents, and treatment can be especially challenging in transplant patients, given potential drug interactions and added toxicities. It is important to distinguish M. immunogenum from other RGM and determine the susceptibility profile to devise a successful treatment plan, particularly in the transplant population in which it can potentially cause severe, disseminated disease.