Toxoplasmosis, a severe complication in allogeneic hematopoietic stem celltransplantation: Successful treatment strategies during a 5-year single-center experience

Toxoplasmosis is a rare but often fatal complication that occurs after pati ents undergo allogeneic hematopoietic stem cell transplant. At our institut ion, toxoplasmosis was diagnosed in 8 of 301 patients who received stem cel l transplants. Disseminated toxoplasmosis with a rapid fatal course was obs erved in 2 patients. Six patients had cerebral toxoplasmosis diagnosed on t he basis of neurological signs and observation of the patients' mental conf usion, seizures, and typical lesions (which were assessed by computed tomog raphy, magnetic resonance imaging, or both). Seroconversion of antitoxoplas ma immunoglobulin and a discovery of toxoplasma deoxyribonucleic acid in th e cerebrospinal fluid (confirmed by use of polymerase chain reaction) were documented in all patients. Treatment consisted of clindamycin therapy (for 2 patients) and of pyrimethamine-clindamycin therapy, sulfadiazine therapy , or both (for 5 patients). Patients showed improvement after therapy, as a ssessed by clinical and radiological means. Three of 8 patients survive-1 w ithout any residual neurological symptoms and 2 with minimal neurological s ymptoms.