Clinical and Epidemiologic Features of Infection With Mycobacterium genavense

Abstract

Infection with M genavense may be responsible for more than 10% of disseminated nontuberculous mycobacterial infections in patients with human immunodeficiency virus infection. Its clinical presentation and response to treatment are similar to those of infection with M avium-intracellulare complex.

A 36‐year‐old female from Kuwait with AIDS presenting with fever and abdominal pain

“…M. genavense is a fastidious, slow-growing, nontuberculous mycobacterium best known for causing opportunistic infections in patients with AIDS and in solid-organ transplant patients (Hoefsloot et al, 2013;Pechere et al, 1995). The clinical features of disseminated M. genavense resemble those of disseminated MAC infection (Thomsen et al, 1999).…”

Early Diagnosis of DisseminatedMycobacterium genavenseInfection

“…genavense causes up to 12.8% of all nontuberculous mycobacteria infections in AIDS patients; these infections are clinically similar to those caused by the M. avium complex (1,6 M. genavense infections occur only rarely in persons other than AIDS patients (as in the present case), but they always occur in immunocompromised persons (7,8). To date, only 1 case of disseminated infection has been reported in a solid-organ (kidney) transplant recipient; the diagnosis was made by molecular identifi cation in isolates from blood and marrow cultures.…”

Gamma Interferon Is Essential for Clearing Mycobacterium genavense Infection

“…It would seem that M. genavense needs time to establish infection even in GKO mice, and macrophages and/or T cells might only respond by releasing proinflammatory mediators after a certain threshold of bacterial numbers is reached. This would reflect the situation in humans, where a prolonged course of M. genavense infection with minor symptoms is followed by overgrowth in enlarged lymph nodes and spleens, leading to the requirement for medical attention (22,26). In GKO mice, typically ordered granuloma formation with epithelioid cell differentiation did not occur, again reminiscent of the lesions present in immunodeficient patients with disseminated M. genavense infection (5,22).…”

“…In GKO mice, M. genavense elicited a chronic inflammatory response, resulting in marked splenomegaly and extensive lymphadenopathy. Granulomatous lesions in the livers of GKO mice were diffuse, were composed of monocytes, neutrophils, and CD3؉ cells, and were histochemically negative for inducible nitric oxide synthase.Mycobacterium genavense is an opportunistic mycobacterium frequently recovered from pet animals (16) that mainly infects immunocompromised patients, particularly those with AIDS (5,22,26). Recently, however, M. genavense has also been detected in the lymph nodes of patients with no apparent primary immune deficiency (2,3,19).…”

“…Mycobacterium genavense is an opportunistic mycobacterium frequently recovered from pet animals (16) that mainly infects immunocompromised patients, particularly those with AIDS (5,22,26). Recently, however, M. genavense has also been detected in the lymph nodes of patients with no apparent primary immune deficiency (2,3,19).…”