Total knee prosthesis infected with Mycobacterium tuberculosis.

Mycobacterium tuberculosis (MTB) infection of a prosthetic joint is rarely reported in developed countries.1 Typically, MTB infection involves the hips or knees, and the infection can occur secondary to crushing and degradation of the granuloma during surgery or, less commonly, from distant foci spreading through the blood. In the present case, MTB infection likely resulted from haematogenous spread since multiple hot spots suggestive of MTB infection were noted in other sites. Early diagnosis allows for antitubercular therapy with retention of the prosthesis, while late diagnosis frequently results in removal and reimplantation of the joint. To avoid major surgery, a high index of suspicion is required to diagnose prosthetic joint tuberculosis.