Abstract
Introduction Nephrotic syndrome, an unusual clinical presentation of IgA nephropathy (IgAN), occurs only in a few cases. The data regarding its clinical characteristics and treatment outcomes are lacking. Material and methods In this retrospective analysis, we reviewed kidney biopsies conducted between January 2007 and December 2018. All patients with biopsy-proven IgAN and clinical presentation of nephrotic syndrome were included. Results Sixty-seven (11.9%) out of 560 patients with primary IgAN had nephrotic syndrome as the first clinical presentation. On MEST-C scoring, the baseline estimated glomerular filtration rate (eGFR) was significantly lower in the presence of segmental sclerosis (S1) (p=0.04) and >25% tubular atrophy/interstitial fibrosis (T1/2) (p=0.004). With immunosuppression, complete remission (CR), partial remission (PR), and no response (NR) occurred in 28 (41.8%), 32 (47.8%), and 7 (10.4%) patients, respectively. During the median follow-up of 190 weeks, the median absolute change in eGFR was significant between CR and NR groups (p=0.002), and PR and NR groups (p=0.02); however, it was not significant between CR and PR groups (p=0.14). In the CR, PR, and NR groups, 9, 15, and 7 patients had eGFR losses of ≥15 ml/min (p=0.004). No patient in the CR group, one in the PR group, and three in the NR group progressed to end-stage kidney disease (ESKD) (p=0.003). Further, none of the MEST-C scores correlated with the clinical outcome parameters. Conclusion Immunosuppression in treating IgAN accompanied by nephrotic syndrome helps in proteinuria remission. Achieving remission, whether complete or partial, delays disease progression and improves renal survival. Moreover, the baseline eGFR was significantly lower when S1 and T1/2 lesions were present in kidney biopsies.