Disseminated nontuberculous infections with Mycobacterium genavense during sarcoidosis

Disseminated Mycobacterium genavense infection in a patient with a history of sarcoidosis

We present a case of Mycobacterium genavense infection in a man in his 60s with a history of sarcoidosis, treated for 24 years with systemic corticosteroids and later methotrexate as monotherapy. He presented with low grade fever, dyspnoea and right-sided thoracic pain and was admitted due to a treatment-refractory infection. After a prolonged period of symptoms and diagnostics, acid-fast bacilli were demonstrated in pleural fluid and PCR revealed M. genavense The patient was treated with intravenous amikacin, peroral azithromycin, rifampicin and ethambutol for a total of 18 months, with a good clinical and radiological treatment response. Infection with M. genavense is rare in HIV-negative immunocompromised hosts. Diagnosing and treating mycobacterial infections, especially for more rare species, remains a challenge as clinical evidence is sparse. Nonetheless, the disease-causing infection must be considered in symptomatic and immunocompromised patients.

An unusual case of abdominal mycobacterial infection: Case report and literature review

This article presents a case of an HIV-infected paediatric patient with an unusual Mycobacterium genavense infection with predominantly abdominal organ involvement.

Mesenterial involvement of Mycobacterium genavense infection: hard to find, hard to treat

Mycobacterium genavense is a rare pathogen affecting severely immunosuppressed patients. We report the case of persistent relapsing M. genavense infection in a 48-year-old African man with a positive diagnosis of HIV infection. Despite being under effective antiretroviral therapy with partial immune reconstitution, he developed irreversible long-term abdominal complications, possibly due to persistent M. genavense infection and sustained inflammation. Case management consists of individual risk assessment, close follow-up and personalised treatment strategies concerning the duration of antimycobacterial therapy and early application of steroids. Patients with profound immunosuppression, a high viral load at HIV diagnosis and a high burden of M. genavense, appear to be at higher risk. The pathogenicity of this complication is not well known and its optimal management has still to be determined.

Mycobacterium genavense Infections in a Tertiary Hospital and Reviewed Cases in Non-HIV Patients

Mycobacterium genavense is a relatively new species of nontuberculous mycobacterium reported to cause disseminated infections in patients with AIDS and later on in non-HIV immunosuppressed patients. We describe clinical and laboratory features and response to therapy in 7 patients, three of them with HIV infection and four non-HIV-three organ transplant recipients and one with hyper-IgE syndrome-in Valencia, Spain, in a ten years period. We then summarize the published cases of M. avium complex infection, with invasion of peripheral blood, liver, spleen, bone marrow, lymph nodes, and lungs. In clinical samples a large number of acid-fast bacilli were observed. M. genavense grew only from liquid media and after a prolonged incubation period. Its identification was accomplished through molecular methods. Patients were treated with prolonged combinations of antimicrobial agents. There was clinical favourable outcome in 4 patients.

Granulomatous lesions in bone marrow: clinicopathologic findings and significance in a study of 48 cases

PURPOSE

Granulomas in bone marrow are an infrequent finding related to various disorders. The aim of this study was to review our clinical experience with granulomatous bone marrow disease and to describe the contributions of recent diagnostic tools, such as (18)F-Fluorodeoxyglucose positron emission tomography ((18)F-FDG-PET) and molecular biology.

METHODS

Clinical, laboratory and morphological data on patients with a granuloma based on bone marrow biopsy analysed in the University Hospital Lyon from May 2004 to July 2010 were reviewed.

RESULTS

We identified 57 cases among 9641 bone marrow biopsies, representing an incidence of 0.59% in the series and an annual incidence of 9.5 cases per year. Nine biopsies performed for staging a known pathology were excluded from further analysis. Among the 48 remaining patients, associated disease was demonstrated in 79%, with infections being the most common (33%), following by sarcoidosis (21%), malignancy (19%) and therapy-induced granulomas (6%). One previously unpublished entity is described: infection with Bartonella henselae diagnosed using molecular biology from node and skin biopsies in two renal transplant patients. (18)F-FDG-PET, performed in 13 cases, showed hypermetabolic foci consistent with sarcoidosis in two cases. Positive PCR result for an infectious pathogen was obtained in three bone marrow samples (Mycobacterium tuberculosis, n=1; Mycobacterium genavense, n=2).

CONCLUSION

In comparison to previous research, our study reports high proportions of cases caused by sarcoidosis and unknown causes. (18)F-FDG-PET could show signs consistent with sarcoidosis and molecular biology is useful for the detection of fastidious bacteria in immunocompromised patients.