Glomerulitis and endothelial cell enlargement in C4d+ and C4d- acute rejections of renal transplant patients.
In acute rejection after renal transplant, glomerulitis is characterized by mononuclear cells in glomerular capillaries and endothelial cell enlargement. In association with C4d deposition in peritubular capillaries, glomerulitis is a feature of acute antibody-mediated rejection. Prognosis in C4d(+) rejection is poorer than in C4d(-) rejection. We measured the glomerular endothelial cell area in C4d(+) and C4d(-) acute rejections by morphometry. In 90 acute rejection biopsies, glomerulitis was present in 36 cases (group G) and absent in 54 (group G0). In biopsies without rejections and in C4d(-) biopsies of group G0, glomerular endothelial cell area was not significantly different. In C4d(-) and C4d(+) biopsies of group G, the area in inflamed glomeruli was greater than that in C4d(-) biopsies of group G0 (P < .02 and P < .006, respectively). In C4d(+) biopsies of group G0, it was, unexpectedly, greater than in C4d(-) biopsies of group G (P < .01). Circulating posttransplant anti-human leukocyte antigen class I and class II antibodies correlated with increased endothelial cell area (P < .02). Glomerulitis was associated with diffuse C4d deposition (odds ratio [OR], 4.27; P < .004); C4d deposition was associated with steroid resistance (OR, 4.97; P < .002). Only in C4d(+) rejections did the presence of glomerulitis increase this association (OR, 9.17; P < .02). In conclusion, we quantified an increase of endothelial cell area in glomerulitis of C4d(+) and C4d(-) acute rejections (group G). An increase of this area in C4d(+) biopsies without glomerulitis (group G0) suggests complement-mediated damage in the absence of mononuclear cell margination.
Department of Medicine and Aging Science, University of Chieti, 66100 Chieti, Italy.
Francesca B
FB
Aiello
Lucrezia
L
Furian
Mila
M
Della Barbera
Stefano
S
Marino
Michela
M
Seveso
Massimo
M
Cardillo
Elisa S
ES
Pierobon
Emanuele
E
Cozzi
Paolo
P
Rigotti
Marialuisa
M
Valente
D000328:Adult; D000368:Aged; D049108:Cell Enlargement; D015935:Complement C4b / Q000276:immunology*; D042783:Endothelial Cells / Q000276:immunology / Q000473:pathology*; D005260:Female; D005500:Follow-Up Studies; D005921:Glomerulonephritis / Q000276:immunology / Q000473:pathology*; D006084:Graft Rejection / Q000276:immunology / Q000473:pathology*; D006801:Humans; D007678:Kidney Glomerulus / Q000276:immunology / Q000473:pathology; D016030:Kidney Transplantation / Q000276:immunology / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D010446:Peptide Fragments / Q000276:immunology*
D010446:Peptide Fragments; D015935:Complement C4b; C032261:complement C4d