Toxoplasmosis as an Early Complication of Allogeneic Hematopoietic Cell Transplantation.

• Toxoplasmosis is a rare but potentially severe complication after allogeneic hematopoietic cell transplantation (HCT). • In this consecutive study of 419 allogeneic HCT recipients in France, the incidence of toxoplasmosis was 4%. • Seven of the 17 observed cases occurred before day 30 (median, day 22) and were especially severe compared with later cases, with 5 deaths. • We strongly recommend starting PCR screening with the transplant and eventually from conditioning in R+ patients to catch early reactivation. Among 419 consecutive allogeneic hematopoietic cell transplant recipients, we observed 17 (4.0%) cases of toxoplasmosis at a median time of day 45 (range, 6 to 322) after transplant. Seven of these 17 cases occurred before day 30 after transplant. Because of the lack of PCR screening and trimethoprim-sulfamethoxazole prophylaxis before engraftment, the diagnosis of toxoplasmosis was late, and 5 of these 7 patients died. Analyzing these cases, early Toxoplasma blood PCR screening, starting from transplant, is crucial. [ABSTRACT FROM AUTHOR]