title: Is Abnormal Urine Protein/Osmolality Ratio Associated with Abnormal Renal Function in Patients Receiving Tenofovir Disoproxil Fumarate?
abstract: BACKGROUND
  Risk factors for and optimal surveillance of renal dysfunction in patients on tenofovir disoproxil fumarate (TDF) remain unclear. We investigated whether a urine protein-osmolality (P/O) ratio would be associated with renal dysfunction in HIV-infected persons on TDF.
  
  
  METHODS
  This retrospective, single-center study investigated the relationship between parameters of renal function (estimated glomerular filtration rate (eGFR) and P/O-ratio) and risk factors for development of kidney dysfunction. Subjects were HIV-infected adults receiving TDF with at least one urinalysis and serum creatinine performed between 2010 and 2013. Regression analyses were used to analyze risk factors associated with abnormal P/O-ratio and abnormal eGFR during TDF therapy.
  
  
  RESULTS
  Patients were predominately male (81%); (65%) were Caucasian. Mean age was 45.1(±11.8) years; median [IQR] TDF duration was 3.3 years. [1.5-7.6]. Median CD4+ T cell count and HIV viral load were 451 cells/μL [267.5-721.5] and 62 copies/mL [0-40,150], respectively. Abnormal P/O-ratio was not associated with low eGFR. 68% of subjects had an abnormal P/O-ratio and 9% had low eGFR. Duration of TDF use, age, diabetes and hypertension were associated with renal dysfunction in this study. After adjustment for age, subjects on TDF > 5 years had almost a four-fold increased likelihood of having an abnormal P/O-ratio than subjects on TDF for < 1yr (OR 3.9; 95% CI 1.2-14.0; p = 0.024).
  
  
  CONCLUSIONS
  Abnormal P/O-ratio is common in HIV-infected patients on TDF but was not significantly associated with low eGFR, suggesting that abnormal P/O-ratio may be a very early biomarker of decreased renal function in HIV infected patients.
authors.affiliation: Department of Medicine, Division of Infectious Diseases, Mayo Clinic, Rochester, MN, United States of America.
authors.forename: Jasmine R
authors.initials: JR
authors.lastname: Marcelin
authors.affiliation: Department of Medicine, Division of Infectious Diseases, Mayo Clinic Rochester, MN, United States of America.
authors.forename: Melody L
authors.initials: ML
authors.lastname: Berg
authors.affiliation: Department of Internal Medicine, Mayo Clinic, Rochester, MN, United States of America.
authors.forename: Eugene M
authors.initials: EM
authors.lastname: Tan
authors.affiliation: Department of Medicine, Division of Nephrology & Hypertension, Mayo Clinic, Rochester MN, United States of America.
authors.forename: Hatem
authors.initials: H
authors.lastname: Amer
authors.affiliation: Department of Medicine, Division of Infectious Diseases, Mayo Clinic, Rochester, MN, United States of America.
authors.forename: Nathan W
authors.initials: NW
authors.lastname: Cummins
authors.affiliation: Department of Medicine, Division of Infectious Diseases, Mayo Clinic, Rochester, MN, United States of America.
authors.forename: Stacey A
authors.initials: SA
authors.lastname: Rizza
mesh_terms: D000328:Adult; D019380:Anti-HIV Agents / Q000009:adverse effects* / Q000627:therapeutic use; D005260:Female; D005919:Glomerular Filtration Rate; D015658:HIV Infections / Q000150:complications / Q000188:drug therapy*; D006801:Humans; D007668:Kidney / Q000187:drug effects* / Q000503:physiopathology*; D007674:Kidney Diseases / Q000139:chemically induced* / Q000150:complications / Q000503:physiopathology; D007677:Kidney Function Tests; D008297:Male; D008875:Middle Aged; D009994:Osmolar Concentration; D011507:Proteinuria / Q000139:chemically induced* / Q000150:complications / Q000503:physiopathology; D012189:Retrospective Studies; D000068698:Tenofovir / Q000009:adverse effects* / Q000627:therapeutic use
chemical_list: D019380:Anti-HIV Agents; D000068698:Tenofovir