Mycobacterium chimaera infection masquerading as a lung mass in a healthcare worker

Abstract

Mycobacterium chimaera , a nontuberculous mycobacterium, is a member of the Mycobacterium avium complex (MAC). This microorganism has recently gained significant notoriety for its association with outbreaks in patients exposed to contaminated heater –cooler devices used during open heart surgeries. We report a case of Mycobacterium chimaera pulmonary infection in a healthcare worker who presented with cough, low grade fever and weight loss with evidence of a lung mass that was initially thought to be a tumor on CT scan imaging. The patient underwent partial left lung lobectomy and pathology revealed necrotizing granulomas with acid fast bacilli and a culture grew M. chimaera . The patient received combination antimycobacterial therapy according to susceptibility results for twelve months with complete resolution of his symptoms and radiographic findings. Infection Control investigation could not find a source of infection in the hospital where he worked during the last ten years. However, the patient rotated in different hospitals before coming to work at this facility and assisted in surgeries in several operating rooms where the heater-cooler devices in question were used.

Disseminated Mycobacterium chimaera Following Open-Heart Surgery, the Heater–Cooler Unit Worldwide Outbreak: Case Report and Minireview

“…Only one case of vertebral osteomyelitis was reported in a patient with prednisolone treatment, without history of cardiac surgery (46). Cases of disseminated M. chimaera infections were rare until 2015 (25). The involvement of this species in disseminated disease was quite unusual and led to the description of this outbreak associated with cardiac surgery.…”

“…surgery and symptoms (23). The reported mortality rate for these infections was remarkably high, around 50% (24,25). No cases were reported in healthcare workers related to the HCU epidemic.…”

“…Due to identical RAPD-PCR patterns, a deeper investigation was retrospectively conducted and six cases were finally detected in the institution (1). The prospective on-site observations and microbiological sampling in the hospital environment showed that M. chimaera was present in water circuits of the LivaNova HCU (25). HCU are essential components of cardiopulmonary bypass operation used during open-chest heart surgery.…”

International Society of Cardiovascular Infectious Diseases Guidelines for the Diagnosis, Treatment and Prevention of Disseminated Mycobacterium chimaera Infection Following Cardiac Surgery with Cardiopulmonary Bypass

“…Using smoke testing, laminar flow ventilation was insufficient to prevent aerosols containing M. chimaera generated by the 3T-HCD and circulated by the HCD exhaust fan from dispersing towards the surgical field [35,44]. Interestingly, only one suspected pulmonary M. chimaera infection has been reported among exposed operating room personnel [45]. Although factors responsible for this observation have not been defined, hypotheses include: (i) M. chimaera pulmonary disease will only affect those with preexisting pulmonary diseases (e.g.…”

Dengue Neonatal: Relato De Caso De Uma Transmissão Vertical Em Área Endêmica

“…Registra-se que entre os casos de doenças causadas por MNT cerca de 80% são originados por infecções causadas por MAC, com isolados de diferentes espécies em variados contextos geográficos (Busatto et al, 2019). Ademais, o aumento no número de casos diagnosticados por MAC pode estar associado à evolução nos métodos diagnósticos, aumento na expectativa de vida da população, aumento no número de indivíduos imunossuprimidos e maior disseminação do conhecimento sobre esses patógenos no contexto dos serviços de saúde (Rosero;Shams, 2019;Shin et al, 2010).…”