title: Repeat kidney biopsies fail to detect differences between azathioprine and mycophenolate mofetil maintenance therapy for lupus nephritis: data from the MAINTAIN Nephritis Trial.
abstract: BACKGROUND
  In the MAINTAIN Nephritis Trial, azathioprine (AZA) and mycophenolate mofetil (MMF) were compared as maintenance immunosuppressive treatment of proliferative lupus nephritis (LN) after a short-course of intravenous cyclophosphamide. Here, we compare the pathological findings on repeat kidney biopsies between the two groups.
  
  
  METHODS
  Per protocol, repeat renal biopsies were obtained in 30 patients (16 AZA and 14 MMF) at 2 years (±6 months). Baseline and follow-up biopsies were graded according to the International Society of Nephrology/Renal Pathological Society (ISN/RPS) classification. The activity and chronicity indices (AI, CI) were calculated using two different semiquantitative scoring systems (Morel-Maroger and National Institutes of Health). Statistics were performed by non-parametric tests.
  
  
  RESULTS
  The clinical characteristics of the 30 re-biopsied patients only marginally differ from the entire MAINTAIN cohort (105 patients). Clinical baseline and follow-up characteristics of AZA- and MMF-treated re-biopsied patients did not differ. Time (SD) to repeat renal biopsy was 25.0 (2.0) and 26.5 (3.3) months in AZA and MMF patients, respectively. More patients had normal renal biopsies or Classes I/II/V LN at follow-up compared to baseline and conversely, less patients had Class IV LN at follow-up. In both groups, the AI statistically decreased at follow-up compared to baseline, while the CI slightly, but significantly, increased. No differences could be detected between the groups.
  
  
  CONCLUSIONS
  Centralized pathological analyses, including ISN/RPS classification and comparisons of AI/CI, failed to find differences between MMF and AZA at 2 years, a result well in line with the absence of difference in long-term clinical outcome reported elsewhere.
authors: Department of Rheumatology, Cliniques Universitaires Saint-Luc, Université Catholique de Louvain, Brussels, Belgium.
authors: Maria S
authors: MS
authors: Stoenoiu
authors: Selda
authors: S
authors: Aydin
authors: Maria
authors: M
authors: Tektonidou
authors: Isabelle
authors: I
authors: Ravelingien
authors: Véronique
authors: V
authors: le Guern
authors: Christoph
authors: C
authors: Fiehn
authors: Philippe
authors: P
authors: Remy
authors: Michel
authors: M
authors: Delahousse
authors: Peter
authors: P
authors: Petera
authors: Thomas
authors: T
authors: Quémeneur
authors: Carlos
authors: C
authors: Vasconcelos
authors: David
authors: D
authors: D'Cruz
authors: Inge-Magrethe
authors: IM
authors: Gilboe
authors: Michel
authors: M
authors: Jadoul
authors: Alexandre
authors: A
authors: Karras
authors: Geneviève
authors: G
authors: Depresseux
authors: Loïc
authors: L
authors: Guillevin
authors: Ricard
authors: R
authors: Cervera
authors: Jean-Pierre
authors: JP
authors: Cosyns
authors: Frédéric A
authors: FA
authors: Houssiau
mesh_terms: D000293:Adolescent; D000328:Adult; D001379:Azathioprine / Q000627:therapeutic use*; D001706:Biopsy / Q000009:adverse effects; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use*; D015994:Incidence; D007668:Kidney / Q000473:pathology*; D008181:Lupus Nephritis / Q000188:drug therapy* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009173:Mycophenolic Acid / Q000031:analogs & derivatives* / Q000627:therapeutic use; D010146:Pain / Q000453:epidemiology; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D007166:Immunosuppressive Agents; D009173:Mycophenolic Acid; D001379:Azathioprine