title: Determination of renal function in long-term heart transplant patients by measurement of urinary retinol-binding protein levels.
abstract: Significant improvements have been noted in heart transplantation with the advent of cyclosporine. However, cyclosporine use is associated with significant side effects, such as chronic renal failure. We were interested in evaluating the incidence of long-term renal dysfunction in heart transplant recipients. Fifty-three heart transplant recipients were enrolled in the study. Forty-three patients completed the entire evaluation and follow-up. Glomerular (serum creatinine, creatinine clearance measured, and creatinine clearance calculated) and tubular functions (urinary retinol-binding protein, uRBP) were re-analyzed after 18 months. At the enrollment time, the prevalence of renal failure ranged from 37.7 to 54% according to criteria used to define it (serum creatinine > or = 1.5 mg/dL and creatinine clearance <60 mL/min). Mean serum creatinine was 1.61 +/- 1.31 mg/dL (range 0.7 to 9.8 mg/dL) and calculated and measured creatinine clearances were 67.7 +/- 25.9 and 61.18 +/- 25.04 mL min-1 (1.73 m(2))-1, respectively. Sixteen of the 43 patients who completed the follow-up (37.2%) had tubular dysfunction detected by increased levels of uRBP (median 1.06, 0.412-6.396 mg/dL). Eleven of the 16 patients (68.7%) with elevated uRBP had poorer renal function after 18 months of follow-up, compared with only eight of the 27 patients (29.6%) with normal uRBP (RR = 3.47, P = 0.0095). Interestingly, cyclosporine trough levels were not different between patients with or without tubular and glomerular dysfunction. Renal function impairment is common after heart transplantation. Tubular dysfunction, assessed by uRBP, correlates with a worsening of glomerular filtration and can be a useful tool for early detection of renal dysfunction.
authors.affiliation: Laboratório de Imunologia Clínica e Experimental, Disciplina de Nefrologia, Universidade Federal de São Paulo, Rua Botucatu 720, 04023-900 São Paulo, SP, Brazil.
authors.forename: R
authors.initials: R
authors.lastname: Chinen
authors.forename: N O S
authors.initials: NO
authors.lastname: Câmara
authors.forename: S
authors.initials: S
authors.lastname: Nishida
authors.forename: M S
authors.initials: MS
authors.lastname: Silva
authors.forename: D A
authors.initials: DA
authors.lastname: Rodrigues
authors.forename: A B
authors.initials: AB
authors.lastname: Pereira
authors.forename: A
authors.initials: A
authors.lastname: Pacheco-Silva
mesh_terms: D015415:Biomarkers / Q000097:blood / Q000652:urine; D003404:Creatinine / Q000097:blood*; D005260:Female; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate / Q000187:drug effects; D016027:Heart Transplantation / Q000009:adverse effects*; D006801:Humans; D007166:Immunosuppressive Agents / Q000009:adverse effects / Q000627:therapeutic use*; D007678:Kidney Glomerulus / Q000503:physiopathology; D007684:Kidney Tubules / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D051437:Renal Insufficiency / Q000139:chemically induced* / Q000175:diagnosis; D012177:Retinol-Binding Proteins / Q000652:urine*; D016019:Survival Analysis
chemical_list: D015415:Biomarkers; D007166:Immunosuppressive Agents; D012177:Retinol-Binding Proteins; D003404:Creatinine