Work

452Pseudo-Outbreak of Fulminant Toxoplasmosis in Hematopoietic Stem Cell Transplant [HSCT] Recipients

Year: 2014

Type: article

Abstract: Background. Fulminant toxoplasmosis is a rare and difficult to diagnose complication after HSCT. Disseminated toxoplasmosis has a reported incidence of 0.1 to 6% in allogeneic transplants and is often fatal. Methods. We report a cluster of 6 cases of fulminant toxoplasmosis, diagnosed within a 1-year period, at 2 neighboring transplant centers in NYC. Toxoplasmosis was diagnosed by positive serum PCR or at autopsy. Results. Between December 2012 and September 2013, six patients were diagnosed with fulminant toxoplasmosis at MSKCC (4 cases) and NYPH/Weill Cornell (2 cases). The incidence of cases, preceding this study, was 1-2 cases per year at MSKCC and zero over the prior 5 years at NYP/Weill Cornell. Underlying diagnosis were acute lymphoblastic leukemia (2), acute myeloid leukemia, myeloma, lymphoma and myelodysplastic syndrome (1 each). Patients received ex-vivo T-cell depleted peripheral blood stem cell (TCD-PBSC) allograft (3) or umbilical cord + TCD-PBSC allografts (3). Five patients received anti-thymocyte globulin during their conditioning regimen. Five of 6 patients had positive Toxoplasma IgG prior to transplant. All patients presented with fevers prior to developing respiratory failure and death. Median days from transplant to death was 37 days (range 23-135 days). Diagnosis of toxoplasmosis was made by serum PCR (n = 4 patients, range 45,100-4,900,000 copies/ml) or at autopsy (n = 2 patients). None of the patients were taking prophylaxis with activity against toxoplasma prior to diagnosis. No epidemiologic risk factors to explain the increased incidence were identified. Conclusion. We report an unexplained cluster of 6 cases of fulminant and fatal toxoplasmosis, occurring within a 1 year period, in TCD and UCB recipients at 2 centers in NYC. No common epidemiologic link was identified. We urge a high index of suspicion for toxoplasmosis, and prompt investigation using toxoplasma serum PCR, for severely immunosuppressed HSCT recipients who are toxoplasma seropositive and present with unexplained fevers. Disclosures. All authors: No reported disclosures.

Source: Open Forum Infectious Diseases

DOI: 10.1093/ofid/ofu052.318