Abstract 12319: Open-Heart Surgeries Leading to Unexpected Latent Disease - A Rare Case of Disseminated Mycobacterium Chimaera

Abstract

Global reports describe several cases of disseminated Mycobacterium chimaera related to surgical field contamination by specific 3T heater-cooler units utilized in open cardiothoracic procedures. Eventual diagnosis leads to aggressive multidrug regimens and possible surgery, resulting in a high, yet potentially avoidable overall mortality rate. A years-long latency period between a patient’s initial exposure and clinical presentation can make this infection extremely challenging to diagnose. A 68-year-old-male with coronary artery disease (CAD) and a bicuspid aortic valve (BAV) suffered from shortness of breath and palpitations for eight years. An extensive cardiac work-up, including a cardiac MRI, revealed aortic root dilatation and significant CAD involving the left anterior descending coronary artery. The patient underwent an elective BAV repair, aortic root replacement, and single vessel coronary artery bypass surgery without any acute post-operative complications. Approximately four years later, he began experiencing fevers, night sweats, and vision changes. Eventually, he was ultimately diagnosed with disseminated M. chimaera confirmed by tissue biopsy. His treatment course of linezolid, moxifloxacin, ethambutol, and rifabutin, was complicated by adverse effects and complex resistance patterns. The complications he experienced secondary to this disease would eventually include long-standing bacteremia, encephalitis, splenic lesions, and aortic root abscess, which ultimately required open sternotomy for AV replacement and aortic root exchange. This patient remains the sole survivor from his home hospital among several other patients who also underwent cardiac surgeries and subsequently developed disseminated M. chimaera. He has since developed additional spinal involvement described as destructive osteomyelitis/discitis and confirmed via biopsy. As he continues to combat this clinically devastating bacterial pathogen, his multi-system complications with such an insidious presentation serve as a reminder to maintain a high clinical suspicion for the possibility of disseminated mycobacterial and other similar infectious processes in the differential diagnoses of all cardiothoracic surgical patients.