Contribution of Clinically Indicated Repeat Renal Biopsy in Indian Patients with Lupus Nephritis

BACKGROUND: Repeat renal biopsy is usually done for lupus nephritis (LN) flare or resistant disease. We analyzed the changes between first and repeat biopsy and the contribution of repeat biopsy on renal outcome in LN patients. METHODS: This was a retrospective study carried out at a tertiary care center in India. Sixty-two LN patients who underwent repeat biopsy for clinical indications, between January 2012 to December 2016, were included. Clinical and histological parameters at first and second biopsies were compared. Logistic regression analysis was done to determine parameters on repeat biopsy predicting response at last visit. RESULTS: Repeat biopsy was done for relapse in 56% and for resistant disease in 44% patients. Seven (13.7%) out of 51 patients with baseline proliferative histology converted to non-proliferative lesion on second biopsy, while 2 (18.2%) out of 11 with baseline non-proliferative lesion converted to proliferative lesion on second biopsy. On repeat biopsy, the presence of endocapillary proliferation decreased, whereas glomerulosclerosis, interstitial fibrosis/tubular atrophy (IFTA), and glomerular basement membrane thickening increased. At the last visit (median follow-up of 38.6 months after first biopsy and 13.8 months after second biopsy), 79% of patients were in remission and 6.5% needed renal replacement therapy. The presence of IFTA >30% and thrombotic microangiopathy (TMA) on second biopsy independently predicted response at last visit. CONCLUSION: In Indian patients with LN, chronicity markers and superimposed membranous pattern increased on repeat biopsy done for clinical indications. The presence of IFTA and TMA on second biopsy predicted response at last visit.