Disseminated Mycobacterium chimaera infection favoring the development of Kaposi’s sarcoma: a case report

Background: Disseminated Mycobacterium chimaera infection is an emerging disease in people undergone to cardiothoracic surgery, which need to be suspected also with atypical presentations. Case presentation: We report the case of a 74-year-old man with fever of unknown origin, purple nodules on both feet and a history of open-heart surgery. Imaging investigations showed an abscess near aortic bioprosthesis but screening for endocarditis resulted negative and pyrexia did not respond to antibiotic therapy. A biopsy of cutaneous lesions showed HHV8-related Kaposi’s sarcoma, so bone marrow biopsy was executed with evidence of HHV8 localization. Bone marrow and urine mycobacterial cultures resulted positive for M. chimaera and a specific antimicrobial therapy was started, with apyrexia after 7 weeks. Conclusions: M. chimaera infection should be always investigated as a possible etiology of fever of unknow origin in people with a history of open-heart surgical intervention, even with negative mycobacterial blood cultures. The possible role of disseminated infection in inducing immunodepression with the occurrence of other opportunistic diseases (such as Kaposi’s sarcoma) cannot be excluded.