title: Tubulointerstitial nephritis in primary Sjögren syndrome: clinical manifestations and response to treatment.
abstract: BACKGROUND
  Primary Sjögren syndrome (pSS) is a common autoimmune condition which primarily affects epithelial tissue, often including the kidney causing either tubulointerstitial nephritis (TIN) or more rarely, an immune complex related glomerulonephritis.
  
  
  METHODS
  We describe the clinical, biochemical and histological characteristics of 12 patients with pSS related TIN and their response to treatment with antiproliferative agents. All 12 patients were investigated and treated at the UCL Centre for Nephrology in London.
  
  
  RESULTS
  All patients had TIN demonstrated via needle biopsy; immunophenotyping showed that the interstitial infiltrate was predominantly a CD4+ T-cell infiltrate. Urinary acidification testing demonstrated distal renal tubular acidosis in 8 patients. Proximal tubular dysfunction was present in 5 patients. All but 1 patient were treated with antiproliferative agents and most also with a reducing course of steroids. In the treated patients, there was a significant improvement in the serum creatinine and measured GFR.
  
  
  CONCLUSIONS
  Patients with pSS TIN have significant renal impairment and other functional tubular defects. There is a mononuclear lymphocytic infiltrate on renal biopsy and this appears to be mainly a CD4+ T-cell infiltrate. Treatment with mycophenolate (and corticosteroids) improves the renal function in patients with pSS TIN.
authors.affiliation: UCL Centre for Nephrology, UCL Medical School, Rowland Hill Street, London, NW3 2PF, UK. rhydrevans@gmail.com.
authors.forename: Rhys D R
authors.initials: RD
authors.lastname: Evans
authors.affiliation: UCL Centre for Nephrology, UCL Medical School, Rowland Hill Street, London, NW3 2PF, UK. chris.laing@nhs.net.
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Laing
authors.affiliation: Department of Rheumatology, University College London Hospital, NHS Trust, 3rd Floor Central, 250 Euston Road, London, NW1 2PG, UK. c.ciurtin@ucl.ac.uk.
authors.forename: Coziana
authors.initials: C
authors.lastname: Ciurtin
authors.affiliation: UCL Centre for Nephrology, UCL Medical School, Rowland Hill Street, London, NW3 2PF, UK. stephen.walsh@ucl.ac.uk.
authors.forename: Stephen B
authors.initials: SB
authors.lastname: Walsh
mesh_terms: D000305:Adrenal Cortex Hormones / Q000627:therapeutic use; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D009173:Mycophenolic Acid / Q000031:analogs & derivatives / Q000627:therapeutic use; D009395:Nephritis, Interstitial / Q000150:complications / Q000175:diagnosis* / Q000188:drug therapy*; D012859:Sjogren's Syndrome / Q000150:complications / Q000175:diagnosis* / Q000188:drug therapy*; D016896:Treatment Outcome
chemical_list: D000305:Adrenal Cortex Hormones; D007166:Immunosuppressive Agents; D009173:Mycophenolic Acid