Table 1. Clinical testing for identifying potential cases of non-tuberculous Mycobacterium (NTM) following cardiac surgery.

Clinical symptoms/exposure	Specimen and testing recommendations
Asymptomatic AND Cardiothoracic surgery after Nov 1, 2011	None
Symptomatic1 Constitutional: recurrent or prolonged fever, fatigue, shortness of breath, weight loss, night sweats Cardiac: prosthetic valve endocarditis and/or prosthetic vascular graft infection Extracardiac: bone infection, sternotomy surgical wound infection, mediastinitis, hepatitis, bloodstream infection, ocular infection (panuveitis, multifocal chorioiditis, chorioretinitis) Immunologic/embolic: splenomegaly, cytopenia Infants: febrile episodes and failure to thrive. AND Open-chest surgery 3 months to 5 years prior to illness onset	Blood: Request mycobacterial blood culture at local, commercial or reference laboratory as available (Appendix 1). Specific incremental yield of multiple blood cultures is not known at present. A set of 2 cultures collected 12 hours apart is a reasonable option with more specific recommendations to follow as data becomes available. NTM isolation from a sterile site is highly likely to be clinically significant (8) Tissue (including bone), and fluid: Request mycobacterial culture and acid fast staining at local, commercial or reference laboratory as available. Aseptically collect and submit in sterile container without fixative Submit to laboratory with appropriate requisition indicating patient history Refer culture to reference laboratory as necessary for species level discrimination

¹ Symptomatic is defined as: Investigation of NTM infection in patients with prolonged illness (≥3 weeks) AND absence of alternative diagnosis through routine investigation to eliminate common etiologic agents