BK-virus-associated hemorrhagic cystitis in children after hematopoietic stem cell transplantation

BACKGROUND: BK-virus-induced hemorrhagic cystitis (BK-HC) is a serious complication in children undergoing hematopoietic stem cell transplantation (HSCT). Data of BK-HC in children undergoing HSCT are still limited. AIM OF THE STUDY: To describe the epidemiology, clinical course, and outcome of children with BK-HC after HSCT. MATERIALS AND METHODS: The medical records of all children aged 0 to 20 years, who underwent HSCT at Schneider Children's Medical Center between 2000 and 2008 and were diagnosed with BK-HC, were reviewed for demographic, clinical, and microbiological data. Patients in whom BK-HC had developed were compared with patients in whom it did not. RESULTS: Seventeen children (5.3%) acquired BK-HC at 10 to 180 days after HSCT (mean, 57 d); 9 had grade 3 to 4 disease. Bleeding lasted for 4 to 42 days (mean, 14). All patients but 1, who died of unrelated causes, recovered. Follow-up ranged from 6 to 91 months (mean, 35 months). Acute myeloid leukemia, use of cyclophosphamide in the conditioning regimen, unrelated donor, and older age were associated with the development of hemorrhagic cystitis (HC). CONCLUSIONS: The incidence of BK-HC in children after HSCT is relatively low. Its rate of successful resolution is very high. Further prospective studies are required to determine optimal therapy.