Guidance on Mycobacterium chimaera infections associated with heater cooler units used in cardiopulmonary bypass

Publication Date: 20 March 2017

Mycobacterium chimaera (M. chimaera​​) is an environmental non-tuberculous mycobacteria belonging to the Mycobacterium avium complex. It has been recognised as a cause of endocarditis, severe disseminated infection and chronic sternal wound infection in patients who have undergone cardiothoracic surgery.

M. chimaera may manifest many years after surgery undertaken on bypass. Investigations in multiple countries shows this is likely to be transmitted from heater cooler units, which are part of the cardiopulmonary bypass equipment.

The risk of infection is low and control measures are already in place. However, M. chimaera infection can have an insidious and non-specific presentation, is not always identified through conventional microbiology, and requires specific treatment.

This page provides guidance and information for healthcare professionals on infection control and clinical aspects of M. chimaera infection associated with cardiopulmonary bypass.

Guidance​​ for healthcare providers and health professionals

Guidance for the Public

Resource information

Health Protection Scotland
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Reference materials