Extrapulmonary and Disseminated Infections Due to Mycobacterium malmoense: Case Report and Review

Mycobacterium malmoense is a potentially pathogenic species that was first described in 1977.During the past decade M. malmoense has been recognized with increasing frequency as a pulmonary pathogen.More than 180 cases of M. malmoense infection have been reported.Most of these infections affected a previously damaged lung.Other infection sites included the skin, lymph nodes, and bursae.Five cases of disseminated infection have been reported.The antituberculous drugs associated with the most favorable susceptibility patterns are rifampin and ethambutol.Because of the slow growth of M. malmoense on conventional, egg-based bacteriologic media, the incubation time should be >6 weeks; special solid and liquid media are recommended.We report a case of disseminated pulmonary and gastrointestinal infection due to M. malmoense in a patient with AIDS, who was treated successfully with a combination of rifabutin (ansamy- cin), clofazimine, and isoniazid.In addition, we review the characteristics of extrapulmonary and disseminated infections due to M. malmoense.Human disease caused by Mycobacterium malmoense is rare.More than 180 cases of M. malmoense infection have been reported since this potentially pathogenic nontuberculous species of Mycobacterium was first described by Schroder and Juhlin in 1977 [1].Most of these cases consisted of pulmonary disease that, in terms of symptomatology and manifestations, resembled pulmonary infection due to Mycobacterium tuberculosis.Nevertheless, two important differences were noted in cases of infection due to M. malmoense.•(1) a poor correlation between results of in vitro drug susceptibility tests and clinical response to chemotherapy [2-4] and (2) a lack of transmission to healthy contacts (whether such infection can be transmitted to immunocompromised persons has not been decided [5][6][7][8][9][10].Therefore, infection-control and contact-tracing procedures need not be applied in response to M. malmoense infections.In contrast with extensive reports of pulmonary infections [11][12][13][14][15][16][17], case reports of extrapulmonary and disseminated disease due to M. malmoense have been sparse.Parallel to the continuing epidemic of AIDS, an increasing incidence of diseases caused by either M. tuberculosis or nontuberculous mycobacteria (NTM) has been observed [9,18].zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCB