OBJECTIVEHemorrhagic cystitis (HC) is one of the common complications of hematopoietic stem cell transplantation (HSCT), which causes significant pain, prolongs hospitalization, and occasionally results in renal failure and death. This study aimed at investigating the incidence, risk factors, and outcome of HC in children post umbilical cord blood transplantation (UCBT) and peripheral blood stem cell transplantation (PBSCT).

METHODSFrom October 1998 to June the clinical records of 53 pediatric patients (aged 2-18 years with median age of 7.5 years) in our HCST center who underwent UCBT (n = 37) and PBSCT (n = 16) were retrospectively analyzed. Thirty out of 53 patients were diagnosed as hereditary hemolytic anemia (56.6%), and the others as haematological malignancies (43.4%): of whom 8 had acute lymphoblastic leukemia, 12 acute myeloid leukemia, 2 chronic myeloid leukemia and 1 non-hodgkin lymphoma. Conditioning regimen varied according to disease and clinical status, however based on cyclophosphamide (CTX, 120-200 mg/kg) and busulphan (BU, 12-16 mg/kg) in the cohort. Total body irradiation (TBI) or total lymphoid irradiation was added in 7 patients respectively. The patients were divided into regular treatment group (RTG) with 15 cases who received hyperhydration, alkalinizing, diuresis and Mesna during CTX infusion and prostaglandin E1 (PGE1) group (PEG) with 38 cases who received hyperhydration, alkalinizing, diuresis and Mesna plus prostaglandin E1 (0.03 microg/kg.h). The risk factors of HC were examined by univariate and multivariate analysis.

RESULTSIn all, 11 of the 53 transplanted patients developed HC (21%) with a median onset time of day +15 (rage day +2 - +25). HC was classified as early in 4 (36%) and late in 7 (64%), and scored as grade Iin 2 cases (18%), grade II in 4 (36%) and grade III in 5 (46%). There was no significant difference between RTG and PEG in the incidence of HC, however, the incidence was much higher in the group of patients who were > or = 6 years old, positive group of graft-versus-host disease (GVHD) and group of cytomegalovirus (CMV) infection than that in the group of patients who were < 6 years of age (32% vs. 8%, P < 0.05), negative group of GVHD (35% vs. 7%, P < 0.05) and CMV non-infected group (62% vs. 13%, P < 0.05), respectively. Furthermore, by multivariate analysis, > or = 6 years old (OR = 3.53, P < 0.05) and CMV infection (OR = 4.31, P < 0.05) were significant risk factors for HC. Three of 11 patients were treated with bladder irrigation. All patients recovered from HC in a median 12.8 days (range 2-53 days).

CONCLUSIONOlder age (> or = 6 years) as well as CMV infection were the risk factors of HC. Both hyperhydration and Mesna were effective in preventing HC, while addition of PGE1 could not reduce the incidence of HC. The prognosis of HC in children post HSCT was satisfactory.