Disseminated toxoplasmosis following T cell-depleted related and unrelatedbone marrow transplantation

More than 95% of reported cases of disseminated toxoplasmosis following BMT have occurred following an unmodified transplant. Most have been fatal, di agnosed at autopsy and without antemortem institution of specific therapy. From 1989 to 1999, we identified 10 cases of disseminated toxoplasmosis, in 463 consecutive recipients of a T cell-depleted (TCD) BMT, Transplants wer e from an unrelated donor (n = 5), an HLA-matched sibling (n = 4) or an HLA -mismatched father (n = 1). In 40%, both the donor and recipient had positi ve IgG titers against T, gondii pre-transplant; in 30%, only the recipient was sere-positive. Three recipients of an unrelated TCD BMT developed toxop lasmosis despite both donor and host testing negative pretransplant. All 10 patients presented with high grade fever. CNS involvement ultimately occur red in seven patients, with refractory respiratory failure and hypotension developing in nine. Eight of 10 cases were found only at autopsy, involving the lungs (n = 7), heart (n = 5), GI tract (n = 5), brain (n = 8), liver a nd/or spleen (n = 5). The only survivor, treated on the day of presentation with fever and headache, was diagnosed by detection of T, gondii DNA by po lymerase chain reaction (PCR) performed on the blood and spinal fluid. This study demonstrates the similar incidence of toxoplasmosis following TCD BM T and that reported post T cell-replete BMT, and underscores the need for r apid diagnostic tests in an effort to improve outcome.