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

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. To describe the epidemiology, clinical course, and outcome of children with BK-HC after HSCT. 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. 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). 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.