title: The impact of C4d and microvascular inflammation before we knew them.
abstract: It is important to identify prognostically important morphologic criteria in post-transplant management to tailor therapy and improve outcomes. Therefore, using biopsies carried out for cause <1-yr post-transplant, from an era when C4d staining and microvascular inflammation (MVI) were not clinically utilized, we studied the importance of C4d and MVI on graft survival. Snap-frozen first renal allograft biopsy specimens (done for cause) in the first post-transplant year from 1996 to 2001 were stained/examined for C4d, and pathology re-examined by a separate blinded pathologist. Graft outcomes in patients with and without MVI and/or C4d were compared. Of 128 patients, 39 (30.5%) biopsies were C4d+ and 89 (69.5%) were C4d-; 67 (52.3%) had no MVI (MVI-) while 61 (47.7%) had glomerulitis, peritubular capillaritis, or both (MVI+). There were no significant demographic differences between MVI+ and MVI- patients. A greater proportion of C4d+ biopsies was MVI+ (67%) than MVI- (33%; p = 0.004). C4d positivity had no impact on death-censored graft survival (DCGS). In contrast DCGS was worse in MVI+ than MVI- regardless of presence/absence of C4d (p = 0.005). In biopsies for cause carried out <1-yr post-transplant, MVI is associated with decreased DCGS, independent of the presence of C4d.
authors.affiliation: Department of Pediatrics, University of Minnesota Medical Center, Minneapolis, MN 55454, USA. pverghes@umn.edu
authors.forename: Priya
authors.initials: P
authors.lastname: Verghese
authors.forename: Ty
authors.initials: T
authors.lastname: Dunn
authors.forename: Behzad
authors.initials: B
authors.lastname: Najafian
authors.forename: Youngki
authors.initials: Y
authors.lastname: Kim
authors.forename: Arthur
authors.initials: A
authors.lastname: Matas
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D015935:Complement C4b / Q000276:immunology*; D005260:Female; D005455:Fluorescent Antibody Technique; D005500:Follow-Up Studies; D006084:Graft Rejection / Q000209:etiology / Q000473:pathology*; D006085:Graft Survival / Q000276:immunology; D006801:Humans; D007249:Inflammation / Q000209:etiology / Q000473:pathology*; D007674:Kidney Diseases / Q000150:complications* / Q000401:mortality / Q000601:surgery; D016030:Kidney Transplantation / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D010446:Peptide Fragments / Q000276:immunology*; D011183:Postoperative Complications; D011379:Prognosis; D015996:Survival Rate; D014184:Transplantation, Homologous; D014652:Vascular Diseases / Q000209:etiology / Q000473:pathology*; D055815:Young Adult
chemical_list: D010446:Peptide Fragments; D015935:Complement C4b; C032261:complement C4d