The response of the Oxford classification to steroid in IgA nephropathy: a systematic review and meta-analysis

Background: The present review is aimed to evaluate the correlation between pathological features and the response to steroid in the patients with IgA nephropathy according to the Oxford classification, mesangial hypercellularity (M), endocapillary hypercellularity (E), segmental glomerulosclerosis (S), tubular atrophy and interstitial fibrosis (T). Methods: We searched Chinese Biomedical Database, EMBASE, Cochrane Library, PubMed and MEDLINE with all spellings of "IgA nephropathy", "Oxford Classification", and " steroid". Results: 5 studies with 637 patients were eligible for inclusion. The analysis showed that M1, S1, and T1/2 was strongly associated with the prediction to steroid resistance when compared with M0 [ odds ratio (OR) 1.89, 95% confidence interval (CI) 1.01 -3.56, P < 0.05], S0 (OR 2.24, 95% CI 0.99 -5.08, P = 0.05) and T0 (OR 2.16, 95% CI 1.29 -3.63, P = 0.004) respectively. There is no difference in steroid sensitivity between E0 and E1 (P = 0.55). The pooled OR of steroid resistance for E1 versus T1/2 is 0.50 (P = 0.04). Conclusion: IgA nephropathy patients with serious pathological changes (M1, S1, and T1/2) were more resistant to steroid than slight ones (M0, S0, and T0), and E1 is better response to steroid therapy than T1/2.