Mycobacterium abscessus bacteremia complicated by sepsis and septic shock in a patient with multiple comorbidities: a case report

Introduction Mycobacterium abscessus is a rapidly growing nontuberculous mycobacterium that most commonly causes pulmonary, skin and soft tissue, or postoperative wound infections. Bloodstream infection due to M. abscessus is uncommon and is usually reported in patients with immune dysfunction, major comorbidity, or healthcare-associated exposure. Case presentation We describe a 66-year-old man who presented with recurrent fever, myalgia, fatigue, dizziness, cough, and urinary urgency. His medical history was notable for poorly controlled type 2 diabetes mellitus, hypertension, prior cerebral infarction, coronary artery bypass grafting, lumbar spine surgery, and a recent episode of septic shock caused by Mycobacterium abscessus . During hospitalization, he developed recurrent high-grade fever and hemodynamic instability consistent with septic shock. Blood cultures yielded M. abscessus , while sputum smear microscopy demonstrated acid-fast bacilli; GeneXpert testing was negative for Mycobacterium tuberculosis . Species identification was established by MALDI-TOF mass spectrometry and further verified by melting-curve analysis. Additional evaluation showed persistent systemic inflammation, thrombocytopenia, cardiac dysfunction, and impaired cellular immunity. He received combination antimicrobial therapy together with supportive treatment, but remained intermittently febrile and symptomatic. He was discharged against medical advice on hospital day 4 at his family’s request. Conclusion This case highlights that M. abscessus bacteremia may cause severe sepsis and septic shock in medically complex patients even in the absence of classical immunosuppressive therapy. Early clinical suspicion, culture-based microbiological confirmation, exclusion of tuberculosis, and timely individualized multidrug treatment are essential in patients with recurrent fever and poor response to conventional antibacterial therapy.