The Oxford classification of IgA nephropathy: single centre experience

The Oxford classification for the pathological classification of a glomerular disease in IgA nephropathy was established and published in 2009. Four of the pathological variables: 1) mesangial hypercellularity score, 2) segmental glomerulosclerosis, 3) endocapillary hypercellularity and 4) tubular atrophy/interstital fibrosis were presented as having value in predicting renal outcome in this glomerular disease. These features were recommended to be taken into account for predicting the outcome. In our study, we correlated these four variables with the outcome of the disease in 40 adult patients with IgA nephropathy. Standard histopathologic procedure was used to determine four variables as 0/1. The results were compared with renal outcome, clinical data were obtained from the out-patient files of the patients. The whole follow-up period was 3-27 years. The average survival of the whole group was 10.8±7.47 years (M±SD). Mesangial hypercellularity was confirmed to be associated with the renal outcome (p=0.047), as well as glomerular sclerosis (p=0.009), endocapillary hypercellularity (p=0.001) and tubular atrophy/interstitial fibrosis (p=0.045). When we analysed only patients with a severe form of the disease (nephrotic syndrome; patients treated with immunosuppression), the survival of the patients was associated only with the degree of tubulointerstitial changes (p=0.018). Analysing separately patients with mild clinical form, we found only a predictive value of segmental glomerulosclerosis on renal survival.