Disseminated Mycobacterium genavense in the immunocompromised: A Case Series at Mayo Clinic Rochester

Abstract

Background Mycobacterium genavense can cause serious disease in the immunocompromised. We report our experience with this uncommon infection.MethodsRetrospective review of M. genavense infection at Mayo Clinic (2010–2017).ResultsThree patients were diagnosed with M. genavense from 2010 to 2017 (Table 1). Lymph node biopsy noted non-necrotizing granulomatous inflammation with AFB in 2 patients. Delayed growth in culture was noted after at least 6 weeks incubation. All patients were started on mycobacterial therapy; no isolate grew sufficiently for drug susceptibility testing.AgeGenderRisk factorPresentationMicrobiologyAntimicrobialsManagementOutcome51MRenal transplant Prednisone2 months right TKA painPositive right knee operative culture at 12 weekCiprofloxacin Ethambutol Rifampin ClarithromycinTKA resection + arthrodesis 24 mo antimicrobials9 y – no relapse66FAzathioprine Idiopathic CD4 lymphopeniaAbdominal pain, fever, weight lossIntra-abdominal lymphadenopathy (Figure 1 and 2)Positive mesenteric lymph node culture at 8 week, blood cultures at 6 weekClarithromycinMoxifloxacinRifabutinSymptoms resolvedExpired from stroke - 7 mo36FAIDSAbdominal painIntra-abdominal lymphadenopathyPositive mesenteric lymph node culture at 11 weekClarithromycin Rifabutin EthambutolSymptoms improved at 1 moLost to followupConclusion M. genavense is an environmental mycobacteria, it rarely causes infection in non-HIV hosts. Our cases involved advanced HIV, solid organ transplant and idiopathic CD4 lymphopenia. Presentation with GI and systemic symptoms is common, pulmonary and cutaneous less so. Growth in culture requires prolonged incubation (8–12 weeks) in broth media with Mycobactin J supplementation. Positive pathological examination for AFB organisms, negative probes for MTB or MAC combined with persistently negative cultures, should raise the suspicion for this organism in the right clinical setting. It is generally susceptible to rifamycins, fluoroquinolones and macrolides; resistant to isoniazid and sometimes pyrazinamide. Immunosuppression should be reduced if possible to speed recovery. Duration of therapy is usually at least 12 months for disseminated disease, depending on response and immunosuppression.Disclosures All authors: No reported disclosures.