title: Calcineurin inhibitors and proximal renal tubular injury in renal transplant patients with proteinuria and chronic allograft nephropathy.
abstract: BACKGROUND
  Chronic allograft nephropathy (CAN) is commonly associated with proteinuria. In native nephropathies, proteinuria is linked with proximal renal tubular damage. This study uses regression analysis to link proteinuria with urinary N-acetyl-beta-d-glucosaminidase (NAG) as a marker of tubular injury or hyperfunction in renal transplant patients.
  
  
  METHODS
  Proteinuria and urinary NAG were measured and regression analysis applied in 105 transplant patients (42 with CAN). Most were receiving calcineurin inhibitor-based immunosuppression (cyclosporine, n=60; tacrolimus, n=26; and neither drug, n=19). Patients with native nephropathies (n=96) and volunteers (n=21) were also studied.
  
  
  RESULTS
  Urinary NAG increased with increasing proteinuria. However, patients taking calcineurin inhibitors had higher urinary NAG at any level of urinary protein than those on alternative therapy, or in native nephropathies.
  
  
  CONCLUSIONS
  In groups of transplant patients taking different immunosuppressive regimens, regression analysis of urinary NAG against urinary protein can identify the separate effects of drug-related tubular injury or hyperfunction from that of proteinuria.
authors.affiliation: University Department of Medicine, Royal Liverpool University Hospital, Liverpool, United Kingdom.
authors.forename: J Michael
authors.initials: JM
authors.lastname: Bone
authors.forename: Alieu B
authors.initials: AB
authors.lastname: Amara
authors.forename: Alan
authors.initials: A
authors.lastname: Shenkin
authors.forename: Abdul
authors.initials: A
authors.lastname: Hammad
authors.forename: Robert A
authors.initials: RA
authors.lastname: Sells
authors.forename: John L
authors.initials: JL
authors.lastname: Alexander
authors.forename: Frank
authors.initials: F
authors.lastname: McArdle
authors.forename: Rana
authors.initials: R
authors.lastname: Rustom
mesh_terms: D000118:Acetylglucosaminidase / Q000652:urine*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D065095:Calcineurin Inhibitors; D002908:Chronic Disease; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents / Q000009:adverse effects*; D016030:Kidney Transplantation / Q000009:adverse effects*; D007687:Kidney Tubules, Proximal / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011507:Proteinuria / Q000209:etiology*; D012044:Regression Analysis; D014184:Transplantation, Homologous
chemical_list: D065095:Calcineurin Inhibitors; D007166:Immunosuppressive Agents; D000118:Acetylglucosaminidase