title: Prognostic Significance of Creeping Proteinuria in the First Year After Transplantation.
abstract: BACKGROUND
  Proteinuria changes have a prognostic significance in proteinuric nephropathies. Proteinuria has been related to kidney transplant outcomes, but there are no information about the impact of increasing proteinuria during the first year on long-term graft and patient survival.
  
  
  METHODS
  Retrospective cohort study of 591 kidney transplants to analyze the effect on long-term prognosis of: proteinuria at 3 (n = 591) and 12 (n = 583) months (no proteinuria: 150-299 mg/24 hours, 300-999 mg/24 hours, and ≥1 g/24 hours), and changes in proteinuria during the first year in such patients with proteinuria at 3 months (reduction ≥50% of proteinuria from 3 to 12 months, variation <50%, and increase ≥50% or "creeping proteinuria") (n = 283).
  
  
  RESULTS
  Higher levels of proteinuria, at both 3 and 12 months, were progressively related to lower graft survival (P < 0.0001). Proteinuria at 12 months was related to mortality (P = 0.026). Creeping proteinuria, which was present in 35 patients (12.4%), was related to graft failure (P < 0.0001) and mortality (P = 0.030), even at lower levels of proteinuria at 3 months. De novo HLA antibody development was the only factor related to creeping proteinuria (hazard ratio, 2.946; 95% confidence interval, 1.158-7.491; P = 0.023).
  
  
  CONCLUSIONS
  Creeping proteinuria during the first year was associated with long-term graft failure and mortality and could be considered as a surrogate of kidney disease progression in the renal transplant population, as it is in proteinuric nephropathies. It could also be viewed as an expression of immunological damage.
authors.affiliation: 1 Department of Nephrology, Hospital Universitari Dr Peset, Valencia, Spain. 2 Department of Medicine, University of Valencia, Valencia, Spain.
authors.forename: Asunción Sancho
authors.initials: AS
authors.lastname: Calabuig
authors.forename: Eva Gavela
authors.initials: EG
authors.lastname: Martínez
authors.forename: Julia Kanter
authors.initials: JK
authors.lastname: Berga
authors.forename: Sandra Beltrán
authors.initials: SB
authors.lastname: Catalán
authors.forename: Ana Isabel Avila
authors.initials: AI
authors.lastname: Bernabeu
authors.forename: Luis Manuel Pallardó
authors.initials: LM
authors.lastname: Mateu
mesh_terms: D000328:Adult; D005260:Female; D005500:Follow-Up Studies; D006084:Graft Rejection / Q000150:complications* / Q000175:diagnosis / Q000453:epidemiology; D006085:Graft Survival; D006801:Humans; D015994:Incidence; D007677:Kidney Function Tests; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011507:Proteinuria / Q000453:epidemiology / Q000209:etiology*; D012189:Retrospective Studies; D013030:Spain / Q000453:epidemiology; D015996:Survival Rate / Q000639:trends; D013997:Time Factors