We describe 3 patients who developed atypical manifestations of Mycobacterium avium complex (MAC) infection >10 months (range, 3-16 months) after attaining sustained CD4(+) T cell counts of >100 cells/microL while receiving antiretroviral therapy and not receiving MAC prophylaxis. The common features of these cases include the degree of immune reconstitution, the unusual locations of the infections, and the absence of a systemic inflammatory response. The low rate of these unusual MAC infections does not warrant continuation of primary or secondary prophylaxis after presumed immune reconstitution.