Mycobacterium chelonae infection following a total knee arthroplasty.

Infection following total knee arthroplasty is a major cause of implant failure, with an incidence of infections between 1 and 12%. Although there have been no previously reported cases of infection with Mycobacterium chelonae following total knee arthroplasty, this mycobacterium appears to be a potential pathogen in arthroplasty. When infection following total knee arthroplasty is evident but standard cultures come back negative, atypical mycobacterium infection should be considered. Mycobacterium chelonae does not grow in the normally allotted culture time, so false negative results are common. Once identified, M. chelonae is difficult to treat because of its resistance to standard drug therapies. Details of the first reported successful diagnosis and treatment of an infection with M. chelonae following a total knee arthroplasty are reported.