Background: Acute cellular rejection remains a major
proplem in the management of patients during the early
phase after renal transplantation (Erren et al., 1999).
Aim: Immunohistochemical study of cellular subpopulations
infiltrating rejecting renal allografts in addition to
classification by Banff schema 97 with correlation of both
to graft survival to determine the prognostic values of
these criteria.
Materials and methods: Ninety two biopsy specimens
from 61 patients who experienced acute graft rejection in
Urology and Nephrology Center-Mansoura Faculty of
medicine were selected. The biopsy specimens were
grouped according to revised Banff 97, in addition to indirect
immunoperoxidase staining of interstitial inflammatory
infiltrate using six monoclonal antibodies listed in Table
(1). Follow up regularly till the end of December 2000
with recording number of rejection episodes and graft survival.
Results: The 92 biopsies were classified according to
revised Banff schema 97 into group of suspicious for rejection,
n=40, type I rejection, n=30, type II rejection,
n=18 and type HI, n=4. Statistical analysis revealed significant
correlation between grading by Banff schema 97, total
number of biopsies, total number of graft episodes, vasculitis,
pattern of infiltrate and graft survival. While
glomerulitis, tubulitis and severity of infiltrate had no significant
relation to graft survival. The immunohistochemical
staining revealed predominance of T-lymphocyte infiltrate,
mainly T4, followed by cytotoxic cells and
macrophage, the natural killer and B-cells participate in renal
allograft rejection but without significant value on
graft survival.
Conclusion: Histopathological and immunohistochemical
analysis of interstitial inflammatory infiltrate of renal
allograft during acute rejection support the role of cellular
immune response, the immunohistochemical analysis has
no prognostic value, while the revised Banff schema (97),
clinical data such as number of biopsies, number of episodes
of rejection and diffuse pattern of infiltrate are associated
with poor graft survival. At the same, the degree of
vasculitis is the important prognostic indicator for graft
outcome. |
