View source for Mycobacterium chimaera

==Background==
===Microbiology===
* A member of the [[Mycobacterium avium complex]]

===Epidemiology===
* A global outbreak of ''Mycobacterium chimaera'' infections was associated with point-source contamination of Stöckert 3T-HCD heater-cooler units (HCUs) used in cardiac bypass
* Higher rates in mainland Europe, followed by UK, followed by North America

===Pathophysiology===
* The HCUs aerosolized mycobacteria into the surgical field

==Clinical Manifestations==
* Median incubation period was 14.5 months (range 6 weeks to 5 years), with 80% of patients becoming unwell during the first two years
* Duration of symptoms median 7 weeks but up to 1 year
* Most commonly presented with unexplained fever
* Constitutional symptoms are common
* Caused prosthetic valve endocarditis, aortic graft infection, surgical site infections, and disseminated disease affecting liver, spleen, bone marrow, spine, skin, and bone
* Lymphopenia and thrombocytopenia are common, as is elevated ALP

==Diagnosis==
* Culture in general has sensitivity of 68% but increases to essentially 100% with two cultures
** Blood, urine, sputum, tissue, et cetera
* Two blood cultures are about 76% sensitive

==Management==
* No specific guidelines exist for treatment
* Typically use a MAC regimen with [[Is treated by::azithromycin]], [[Is treated by::ethambutol]], and [[Is treated by::rifampin]]
* May need additional aminoglycoside such as [[Is treaed by::amikacin]] for severe disease
* Duration unclear, but at least several months

==Prognosis==
* Poor prognosis, with median survival of30 months from initial surgery and 9 months from start of therapy

==Further Reading==
* ''Mycobacterium chimaera'' infection following cardiac surgery in the United Kingdom: clinical features and outcome of the first 30 cases. ''Clin Microbiol Infect''. 2018. doi: [https://doi.org/10.1016/j.cmi.2018.04.027 10.1016/j.cmi.2018.04.027]

{{DISPLAYTITLE:''Mycobacterium chimaera''}}
[[Category:Mycobacteria]]