Banff 07 classification of renal allograft pathology: updates and future directions (original) (raw)

International standardization of criteria for the histologic diagnosis of renal allograft rejection: the Banff working classification of kidney transplant pathology

Kidney …, 1993

International standardization of criteria for the histologic diagnosis of renal allograft rejection: The Banif working classification of kidney transplant pathology. A group of renal pathologists, nephrologists, and transplant surgeons met in Banif, Canada on August 2-4, 1991 to develop a schema for international standardization of nomenclature and criteria for the histologic diagnosis of renal allogralt rejection. Development continued after the meeting and the schema was validated by the circulation of sets of slides for scoring by participant pathologists. In this schema intimal arteritis and tubulitis are the principal lesions indicative of acute rejection. Glomerular, interstitial, tubular, and vascular lesions of acute rejection and "chronic rejection" are defined and scored 0 to 3+, to produce an acute and/or chronic numerical coding for each biopsy. Arteriolar hyalinosis (an indication of cyclosporine toxicity) is also scored. Principal diagnostic categories, which can be used with or without the quantitative coding, are: (1) normal, (2) hyperacute rejection, (3) borderline changes, (4) acute rejection (grade Ito III), (5) chronic allograft nephropathy ("chronic rejection") (grade Ito III), and (6) other. The goal is to devise a schema in which a given biopsy grading would imply a prognosis for a therapeutic response or long-term function. While the clinical implications must be proven through further studies, the development of a standardized schema is a critical first step. This standardized classification should promote international uniformity in reporting of renal allograft pathology, facilitate the performance of multicenter trials of new therapies in renal transplantation, and ultimately lead to improvement in the management and care of renal transplant recipients. 1 All authors made an intellectual contribution to the writing of this paper. The blinded reviews of panel slides for assessment of reproducibility were conducted

Reproducibility of the Banff schema in reporting protocol biopsies of stable renal allografts

Nephrology Dialysis …, 2002

Background. There is evidence that biopsy of stable renal allografts may be of value in predicting chronic allograft nephropathy, the main cause of graft loss. However, the reproducibility of such histological evaluation has not been tested in this setting. We tested the reproducibility of the Banff schema for this purpose. Methods. We rated acute and chronic changes in 184 protocol biopsies. Individual pathologists at two different Canadian transplant centres reported independently.

Renal allograft biopsies in the era of C4d staining: the need for change in the Banff classification system

Transplant International, 2008

C4d immunostaining in the peritubular capillaries (PTC) is a marker of antibody-mediated rejection (AMR). We evaluated the histopathologic diagnoses of 388 renal transplant biopsies since the implementation of routine C4d immunostaining at our center. Of these, 155 (40%) biopsies had evidence of acute cellular rejection (ACR), out of which 119 (77%) had pure ACR, 31 (20%) had ACR with concomitant features of AMR, and five (3%) had ACR with focal C4d staining. Sixty-four (16%) biopsies exhibited features of AMR [33 (52%) pure AMR, and 31(48%) concomitant AMR and ACR]. One hundred and fifty-five (40%) biopsies had features of interstitial fibrosis and tubular atrophy (IFTA). Of these, 20 (13%) had concomitant AMR [13 (8.5%) had pure AMR and seven (4.5%) had concomitant ACR and AMR]. Creatinine at the time of biopsy was higher in patients with mixed ACR and AMR and the clinical behavior of mixed lesions is more aggressive over time. Despite having a lower serum creatinine at the time of biopsy, patients with IFTA experienced gradual decline in graft function over time. The pathologic findings in renal allograft biopsies are often mixed and mixed lesions appear to have more aggressive clinical behavior. These findings suggest the need for change in the Banff classification system to better capture the complexity of renal allograft pathologies.