title: A clinicopathological study of IgA nephropathy in renal transplant recipients: beneficial effect of angiotensin-converting enzyme inhibitor.
abstract: BACKGROUND
  Prolonging the survival of transplant kidneys is a major task of modern nephrology. It has recently been shown that deteriorating renal function and substantial graft loss were observed in 55% of renal allograft recipients with recurrent IgA nephropathy (IgAN) at long-term follow-up. To gain a useful insight into the therapeutic approach towards protecting allograft kidneys from deteriorating graft function, we compared the histological characteristics of post-transplant IgAN to primary IgAN and investigated the effects of an ACE inhibitor.
  
  
  METHODS
  Twenty-one patients with post-transplant IgAN and 63 patients with primary IgAN were included in the histopathological study. The effectiveness of angiotensin-converting enzyme (ACE) inhibitor treatment in post-transplant IgAN was also studied in 10 patients.
  
  
  RESULTS
  The prevalence of glomeruli with adhesions and/or cellular crescents in primary IgAN was significantly greater than in post-transplant IgAN (P<0.05), but the proportion of glomeruli with segmental sclerosis was similar in both groups. The rate of global obsolescence, and the degree of interstitial fibrosis in post-transplant IgAN were significantly greater than in primary IgAN (P<0.05). The degree of glomerular obsolescence and the severity of interstitial fibrosis correlated with the severity of glomerular lesion in primary IgAN, but not in post-transplant IgAN. In primary IgAN, glomerular diameter significantly correlated with the proportions of glomerular obsolescence, but not in post-transplant IgAN, suggesting that allograft kidneys may be in a hyperfiltration state. Both the blood pressure and the urinary protein excretion significantly improved after ACE-inhibitor treatment (P<0.001).
  
  
  CONCLUSIONS
  In post-transplant IgAN, histopathological lesions indicative of acute inflammatory insults were suppressed, and glomerular hypertrophy, which may relate to haemodynamic burden such as hyperfiltration, was prominent. Preliminary study of ACE-inhibitor treatment in 10 patients showed favourable effects. A future long-term follow-up study is required to establish the effectiveness of ACE inhibitors in treatment of post-transplant IgAN.
authors.affiliation: Departments of Internal Medicine and Therapeutics and Urology, Osaka University Graduate School of Medicine, Sakurabashi Circulate Organ Clinic, School of Health and Sport Sciences, Osaka University, Osaka, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Oka
authors.forename: E
authors.initials: E
authors.lastname: Imai
authors.forename: T
authors.initials: T
authors.lastname: Moriyama
authors.forename: Y
authors.initials: Y
authors.lastname: Akagi
authors.forename: A
authors.initials: A
authors.lastname: Ando
authors.forename: M
authors.initials: M
authors.lastname: Hori
authors.forename: A
authors.initials: A
authors.lastname: Okuyama
authors.forename: K
authors.initials: K
authors.lastname: Toki
authors.forename: M
authors.initials: M
authors.lastname: Kyo
authors.forename: Y
authors.initials: Y
authors.lastname: Kokado
authors.forename: S
authors.initials: S
authors.lastname: Takahara
mesh_terms: D000328:Adult; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000627:therapeutic use*; D005260:Female; D005355:Fibrosis; D005922:Glomerulonephritis, IGA / Q000188:drug therapy* / Q000209:etiology / Q000473:pathology / Q000503:physiopathology*; D006801:Humans; D006973:Hypertension / Q000188:drug therapy / Q000209:etiology; D007211:Indoles / Q000627:therapeutic use*; D007668:Kidney / Q000473:pathology; D007678:Kidney Glomerulus / Q000473:pathology; D016030:Kidney Transplantation; D008297:Male; D011183:Postoperative Complications; D011507:Proteinuria / Q000188:drug therapy / Q000209:etiology; D012598:Sclerosis
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D007211:Indoles; C052035:trandolapril