title: A novel treatment regimen for BK viremia.
abstract: BACKGROUND
  BK viremia, a prerequisite for BK virus nephropathy (BKVN), affects 5% to 16% of pediatric renal transplant recipients (PRTR). We evaluated the safety and efficacy of a novel approach to treating BK viremia using fluoroquinolones and leflunomide in PRTR.
  
  
  METHODS
  We studied 230 PRTR at Mattel Children's Hospital, UCLA, who underwent renal transplantation between January 2003 and October 2010. Nineteen patients were found to have BK viremia. Ciprofloxacin was started when the BK viral load was greater than 625 copies/mL, and patients were switched to leflunomide if BK viral load did not decrease after 2 months of ciprofloxacin therapy. All patients underwent transplant kidney biopsy, and their estimated glomerular filtration rate (eGFR) and BK PCR was measured serially. The side effects of ciprofloxacin and leflunomide were recorded in each patient.
  
  
  RESULTS
  There was a significant decrease in BK viral load in patients treated with ciprofloxacin and leflunomide (P<0.001) with only a small reduction in immunosuppression. BK viremia was associated with a significantly decreased eGFR (P<0.001), and treatment with ciprofloxacin and leflunomide was associated with improved eGFR (P<0.001). This approach resulted in a BKVN rate of only 1%.
  
  
  CONCLUSIONS
  This analysis demonstrates for the first time that, used in a stepwise fashion, ciprofloxacin and leflunomide are effective and safe treatments for BK viremia in PRTR.
authors: 1 Mattel Children's Hospital UCLA, Division of Pediatric Nephrology, Los Angeles, CA. 2 Address correspondence to: Eileen W. Tsai, M.D., Mattel Children's Hospital UCLA, Division of Pediatric Nephrology, Box 951752, Los Angeles, CA, 90095-1752.
authors: Rumina A
authors: RA
authors: Zaman
authors: Robert B
authors: RB
authors: Ettenger
authors: Hay
authors: H
authors: Cheam
authors: Mohammed H
authors: MH
authors: Malekzadeh
authors: Eileen W
authors: EW
authors: Tsai
mesh_terms: D000293:Adolescent; D001739:BK Virus; D002648:Child; D002939:Ciprofloxacin / Q000008:administration & dosage; D005260:Female; D024841:Fluoroquinolones / Q000008:administration & dosage; D005919:Glomerular Filtration Rate; D006801:Humans; D007166:Immunosuppressive Agents / Q000008:administration & dosage / Q000627:therapeutic use; D007555:Isoxazoles / Q000008:administration & dosage; D016030:Kidney Transplantation; D000077339:Leflunomide; D008297:Male; D019384:Nucleic Acid Synthesis Inhibitors / Q000008:administration & dosage; D027601:Polyomavirus Infections / Q000188:drug therapy*; D051437:Renal Insufficiency / Q000628:therapy* / Q000821:virology*; D012189:Retrospective Studies; D016896:Treatment Outcome; D014412:Tumor Virus Infections / Q000188:drug therapy*; D014766:Viremia / Q000150:complications / Q000188:drug therapy*
chemical_list: D024841:Fluoroquinolones; D007166:Immunosuppressive Agents; D007555:Isoxazoles; D019384:Nucleic Acid Synthesis Inhibitors; D002939:Ciprofloxacin; D000077339:Leflunomide