title: Changes in Kidney Function and in the Rate of Tubular Dysfunction After Tenofovir Withdrawal or Continuation in HIV-Infected Patients.
abstract: Longitudinal data on the changes in kidney function and tubular abnormalities in case of tenofovir disoproxil fumarate (TDF) withdrawal or continuation are scarce.
  
  
  
  Prospective study of 228 patients receiving TDF, with 3 sequential determinations of serum creatinine, estimated glomerular filtration rate (eGFR), phosphatemia, and different urinary parameters (protein, albumin, phosphaturia, uricosuria, and glycosuria). Changes were analyzed in patients who interrupted TDF as compared to those who continued the same regimen. Proximal renal tubular dysfunction (PRTD) was defined as ≥2 tubular abnormalities.
  
  
  
  After a median follow-up of 59.5 months, 78 patients (34%) had PRTD, mainly proteinuria (40%) and phosphaturia (61%), and time on TDF explains the severity of tubular alterations and eGFR slopes. In 35 switching patients, there was a rapid and significant eGFR improvement (median +4.1 ml/min per 1.73 m; P = 0.02), leading to a 39%-83% reduction in the prevalence of tubular abnormalities and of PRTD in less than 1 year (66%-39%). In comparison, 193 patients continuing the same regimen for 21.2 months had a small but significant and progressive eGFR decrease (-2.9 mL·min·1.73 m; P < 0.01), and a progressive rise in the prevalence of phosphaturia, uricosuria, and glycosuria (+9%-56%). In linear mixed-effect model, subsequent eGFR impairment was associated with proteinuria and time on TDF, and eGFR improvement with TDF discontinuation.
  
  
  
  Our data support the role of use and time on TDF in eGFR decline and tubular dysfunction. In contrast, TDF withdrawal is followed by a rapid and significant, although partial, recovery of eGFR and tubular abnormalities.
authors.affiliation: Departments of *Infectious Diseases; †Biochemistry; and ‡Nephrology, Ramon y Cajal Hospital, Madrid, Spain.
authors.forename: José L
authors.initials: JL
authors.lastname: Casado
authors.forename: Jose M
authors.initials: JM
authors.lastname: Del Rey
authors.forename: Sara
authors.initials: S
authors.lastname: Bañón
authors.forename: Carmen
authors.initials: C
authors.lastname: Santiuste
authors.forename: Mar
authors.initials: M
authors.lastname: Rodriguez
authors.forename: Ana
authors.initials: A
authors.lastname: Moreno
authors.forename: María J
authors.initials: MJ
authors.lastname: Perez-Elías
authors.forename: Fernando
authors.initials: F
authors.lastname: Liaño
authors.forename: Santiago
authors.initials: S
authors.lastname: Moreno
mesh_terms: D000328:Adult; D000368:Aged; D019380:Anti-HIV Agents / Q000008:administration & dosage* / Q000009:adverse effects*; D005260:Female; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate; D015658:HIV Infections / Q000188:drug therapy*; D006801:Humans; D007015:Hypophosphatemia, Familial / Q000139:chemically induced; D007674:Kidney Diseases / Q000097:blood / Q000139:chemically induced* / Q000473:pathology / Q000503:physiopathology; D007677:Kidney Function Tests; D007687:Kidney Tubules, Proximal / Q000187:drug effects / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D000068698:Tenofovir / Q000008:administration & dosage* / Q000009:adverse effects*; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D019380:Anti-HIV Agents; D000068698:Tenofovir