title: BK Virus-Associated Hemorrhagic Cystitis After Allogeneic Hematopoietic Stem Cell Transplantation in the Pediatric Population.
abstract: OBJECTIVE
  To study the incidence, risk factors, and treatment of hemorrhagic cystitis secondary to BK-virus reactivation (HC-BKV) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) in the pediatric population.
  
  
  METHODS
  Case-control study in which all pediatric patients (0-18 years) who underwent allo-HSCT from September 2009 to January 2014 were followed.
  
  
  RESULTS
  Twenty-nine patients underwent an allo-HSCT. The median age was 9 years (range = 6 months to 15 years), 61% male. The primary diagnosis was acute lymphoblastic leukemia (72.4%). Six (20.7%) developed HC-BKV. In a multivariate analysis of risk factors, it was observed that the reactivation of BK virus was associated with age more than 10 years ( P = .098) and those with positive serology for Epstein-Barr virus ( P = .06). Five of the 6 patients with HC-BKV received cidofovir (CDV) at doses of 3 to 5 mg/kg/week. The treatment lasted a median of 3 cycles (range = 2-5). One of the patients (20%) developed nephrotoxicity. Of the 5 patients treated with CDV, 3 (60%) had a complete response, 1 (20%) partial response, and 1 (20%) no response.
  
  
  CONCLUSIONS
  We conclude that HC-BKV is a frequent complication after allo-HSCT. CDV therapy can be effective but controlled clinical trials are needed.
authors.affiliation: 1 La Fe University Hospital of Valencia, Valencia, Spain.
authors.forename: Pablo
authors.initials: P
authors.lastname: Pérez-Huertas
authors.affiliation: 1 La Fe University Hospital of Valencia, Valencia, Spain.
authors.forename: Margarita
authors.initials: M
authors.lastname: Cueto-Sola
authors.affiliation: 1 La Fe University Hospital of Valencia, Valencia, Spain.
authors.forename: Paloma
authors.initials: P
authors.lastname: Escobar-Cava
authors.affiliation: 1 La Fe University Hospital of Valencia, Valencia, Spain.
authors.forename: José María
authors.initials: JM
authors.lastname: Fernández-Navarro
authors.affiliation: 1 La Fe University Hospital of Valencia, Valencia, Spain.
authors.forename: Carmela
authors.initials: C
authors.lastname: Borrell-García
authors.affiliation: 1 La Fe University Hospital of Valencia, Valencia, Spain.
authors.forename: Asunción
authors.initials: A
authors.lastname: Albert-Marí
authors.affiliation: 1 La Fe University Hospital of Valencia, Valencia, Spain.
authors.forename: Eduardo
authors.initials: E
authors.lastname: López-Briz
authors.affiliation: 1 La Fe University Hospital of Valencia, Valencia, Spain.
authors.forename: José Luis
authors.initials: JL
authors.lastname: Poveda-Andrés
keywords: BK virus; allogeneic hematopoietic stem cell transplantation; cidofovir; hemorrhagic cystitis; pediatric patients