Cutaneous Non-Tuberculous Mycobacterial Infections: Clinical Clues and Treatment Options

Abstract

Among cutaneous infections caused by mycobacteria, those caused by non-tuberculous mycobacteria are the most common ones and their incidence seems to be progressively increasing. These infections could affect both immunocompetent and immunocompromised subjects. The majority of the pathogens have a worldwide distribution, and the transmission of the infection is related to environmental exposure. Mycobacterium ulcerans, the causative agent of the so-called Buruli ulcer, has an endemic distribution that is responsible of this infection mainly in some countries of Africa and Australia. Due to the lack of well-established and satisfactory laboratory tolls, performing a correct diagnosis may be difficult and it is often based on clinical suspicious. Once diagnosis has been obtained or suspected, another problem is to get the correct treatment regimen. The absence of well-established guidelines for the treatment of cutaneous non-tuberculous infections and the lack of randomized trials investigating the efficacy of different antibiotic treatments together with the different drugs susceptibility between mycobacteria of different species and, sometimes, also of the same species can make difficult the choice of treatment basing it on empirical or personal experience instead of scientific data. Usually, combination of different antimicrobial drugs for long periods is needed. This could increase the risk of treatment related side effects and drug–drug interactions resulting in a diminished compliance of the patient to the therapy.