title: Treatment of BK virus-associated hemorrhagic cystitis in pediatric hematopoietic stem cell transplant recipients with cidofovir: a single-center experience.
abstract: BACKGROUND
  BK virus (BKV)-associated hemorrhagic cystitis (BKV-HC) is a severe complication after hematopoietic stem cell transplantation (HSCT). Cidofovir (CDV) has emerged as an effective agent for the treatment of BKV nephropathy, but its use for BKV-HC in pediatric HSCT recipients has not yet been established as a standard therapy.
  
  
  METHODS
  We retrospectively investigated the efficacy and safety of CDV therapy for patients with BKV-HC at a single institution and analyzed the clinical management outcomes.
  
  
  RESULTS
  From April 2009 to July 2011, 12 patients developed BKV-HC at a median of 37 days after transplant (range 15-59 days). The cumulative incidence was 9% and the median peak of the urine BKV load was 2.5 × 10(10) copies/mL (range 1.4 × 10(9) -1.2 × 10(11) copies/mL). Eleven patients received intravenous CDV (5 mg/kg/dose, with probenecid), whereas 1 patient received CDV (5 mg/kg/dose, without probenecid) intravesically. The median duration of therapy was 25 days (range 9-73 days), and a median of 2 doses was given (range 1-4). A reduction of ≥ 1 log in the BKV load was found in 11 patients, while 1 patient did not have any significant change in BKV load. Clinical improvement was observed in all cases, and no HC-related death was observed. CDV-related toxicity occurred in 1 patient (8%) and spontaneously resolved.
  
  
  CONCLUSIONS
  CDV appears to be an effective and safe treatment for BKV-HC in pediatric HSCT recipients, but prospective trials are warranted to support its use.
authors.affiliation: Division of Infectious Diseases, Department of Pediatrics, College of Medicine, The Catholic University of Korea, Seoul, Korea; Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: H J
authors.initials: HJ
authors.lastname: Kwon
authors.forename: J H
authors.initials: JH
authors.lastname: Kang
authors.forename: J W
authors.initials: JW
authors.lastname: Lee
authors.forename: N-G
authors.initials: NG
authors.lastname: Chung
authors.forename: H-K
authors.initials: HK
authors.lastname: Kim
authors.forename: B
authors.initials: B
authors.lastname: Cho
mesh_terms: D000293:Adolescent; D000998:Antiviral Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D001739:BK Virus; D002648:Child; D000077404:Cidofovir; D003556:Cystitis / Q000188:drug therapy* / Q000821:virology; D003596:Cytosine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000627:therapeutic use; D005260:Female; D018380:Hematopoietic Stem Cell Transplantation / Q000009:adverse effects*; D006470:Hemorrhage / Q000188:drug therapy* / Q000821:virology; D006801:Humans; D008297:Male; D063065:Organophosphonates / Q000008:administration & dosage / Q000627:therapeutic use*; D027601:Polyomavirus Infections / Q000097:blood / Q000150:complications* / Q000652:urine / Q000821:virology; D012189:Retrospective Studies; D014412:Tumor Virus Infections / Q000097:blood / Q000150:complications* / Q000652:urine / Q000821:virology; D019562:Viral Load
chemical_list: D000998:Antiviral Agents; D063065:Organophosphonates; D003596:Cytosine; D000077404:Cidofovir
keywords: BK virus; children; cidofovir; hematopoietic stem cell transplantation; hemorrhagic cystitis; pediatric