Microsporidiosis in solid organ transplant recipients: two Enterocytozoon bieneusi cases and review

Microsporidiosis first came to prominence as an opportunistic infection in patients with acquired immunodeficiency syndrome. Microsporidia are now emerging pathogens responsible for severe diarrhea during solid organ transplantation. Two main clinical entities can be identified: infection by Enterocytozoon bieneusi, causing diarrhea with limited treatment options; and infection by Encephalitozoon intestinalis, which may disseminate and usually responds to albendazole treatment. We describe here 2 cases of microsporidiosis caused by E. bieneusi in a renal and a liver transplant recipient, respectively, in whom complete clinical efficacy of a short course of fumagillin therapy was obtained. Long-term microbiological eradication was assessed using classical methods and monitored using a real-time quantitative polymerase chain reaction-based method. Both patients experienced drug-induced thrombocytopenia, which resolved after withdrawal of the treatment. We also review the 18 other previously reported cases of microsporidiosis in transplant recipients. In case of persistent diarrhea in solid organ transplant patients, microsporidiosis should be considered. Based on the present experience, treating E. bieneusi infection with 7 days of fumagillin therapy is adequate to eradicate E. bieneusi in this context.

Identification of prognostic factors in 61 patients with posttransplantation lymphoproliferative disorders

PURPOSE

Prognostic studies of posttransplantation lymphoproliferative disorders (PTLDs) are hindered by the small number of cases at each transplant center. We analyzed prognostic factors and long-term outcome according to clinical manifestations, pathologic features, and treatment and investigated the prognostic value of the non-Hodgkin's lymphoma International Prognostic Index (IPI) in 61 patients with PTLD.

PATIENTS AND METHODS

We studied 61 patients in two institutions who developed PTLD and analyzed factors influencing the complete remission and survival rates.

RESULTS

In univariate analysis, factors predictive of failure to achieve complete remission were performance status (PS) > or = (P =.0001) and nondetection of Epstein-Barr virus (EBV) in the tumor (P =.01). Only a negative link with PS > or = 2 was observed in multivariate analysis. In univariate analysis, factors predictive of lower survival were PS > or = 2, the number of sites (one v > one), primary CNS localization, T-cell origin, monoclonality, nondetection of EBV, and treatment with chemotherapy. The IPI failed to identify a patient subgroup with better survival and was less predictive of the response rate than was a specific index using two risk factors (PS and number of involved sites), which defined three groups of patients: low-risk patients whose median survival time has not yet been reached, intermediate-risk patients with a median survival time of 34 months, and high-risk patients with a median survival time of 1 month.

CONCLUSION

PS and the number of involved sites defined three risk groups in our population. The value of these prognostic factors needs to be confirmed in larger cohorts of patients treated in prospective multicenter studies.