Urine high and low molecular weight proteins one-year post-kidney transplant: Relationship to histology and graft survival

H. Amer, J. C. Lieske, A. D. Rule, W. K. Kremers, T. S. Larson, C. R.Franco Palacios, M. D. Stegall, F. G. Cosio

Research output: Contribution to journalArticle

44 Scopus citations

Abstract

Increased urinary protein excretion is common after renal transplantation and portends worse outcome. In this study we assessed the prognostic contribution of several urinary proteins. Urinary total protein, albumin, retinol binding protein (RBP), α-1-microglobulin, IgG and IgM were measured in banked urine samples from 221 individuals 1 year after renal transplantation (age 52 ± 13 years, 55% male, 93% Caucasian and 82% living donor). Levels of all proteins measured were higher than in normal nontransplant populations. Patients with glomerular lesions had higher urinary albumin than those with normal histology, while those with interstitial fibrosis and tubular atrophy plus inflammation (ci>0, cg = 0, i>0) had higher levels of IgG, IgM, α-1-microglobulin and RBP. Concomitant normal levels of urinary albumin, IgM and RBP identified normal histology (specificity 91%, sensitivity 15%,). Urinary levels of the specific proteins were highly correlated, could not differentiate among the histologic groups, and appeared to result from tubulointerstitial damage. Increased urinary excretion of the low molecular weight protein RBP was a sensitive marker of allografts at risk, predicting long-term graft loss independent of histology and urinary albumin. This study highlights the prognostic importance of tubulointerstitial disease for long-term graft loss. This study examines several urinary proteins derived from kidney transplant recipients one year after transplantation and finds that retinol-binding protein provides additional prognostic information beyond urinary albumin and graft histology.

Original languageEnglish (US)
Pages (from-to)676-684
Number of pages9
JournalAmerican Journal of Transplantation
Volume13
Issue number3
DOIs
StatePublished - Mar 2013

Keywords

  • IgG
  • IgM
  • Spot urine
  • albumin
  • creatinine ratio
  • graft survival
  • protocol biopsies
  • retinol binding protein
  • α 1 microglobulin

ASJC Scopus subject areas

  • Immunology and Allergy
  • Transplantation
  • Pharmacology (medical)

Fingerprint Dive into the research topics of 'Urine high and low molecular weight proteins one-year post-kidney transplant: Relationship to histology and graft survival'. Together they form a unique fingerprint.

  • Cite this