Kidney biopsy in lupus nephritis after achieving clinical renal remission: paving the way for renal outcome assessment

Abstract

The role of repeat kidney biopsy in lupus nephritis with renal remission is unclear. The aim of this study is to assess this role in a real-life scenario. This retrospective, single-centre study included 56 patients with lupus nephritis diagnosed from 1998 to 2019, with an initial kidney biopsy (KB1) at the onset of lupus nephritis and a second kidney biopsy (KB2) after achieving renal remission. Fifty-one (91.1%) patients were women with a median age of 29.9 [23.4–40.6] years at the time of lupus nephritis diagnosis. KB2 were performed after 41.1 [30.1–52.5] months of KB1. At the time of KB2, complete renal response was achieved in 51 (91.1%) patients. Median activity index decreased from a baseline value of 6.5 [2.8–11] to 0 [0–2] (p < 0.001). Chronicity index worsened from 1 [0–2] to 2 [1–3] (p = 0.01). In patients with proliferative/mixed forms at KB2, chronicity index median value increased to 3 [1.5–4], as well as interstitial fibrosis and tubular atrophy $\ge $ 25%, from 5.4% to 13.5%. Persistent histological active lupus nephritis (activity index ≥ 2) was presented in 11 (19.6%) of KB2. There were no differences when comparing immunological parameters between both groups (activity index ≥ 2 versus < 2) at KB2, nor in the percentage of patients who presented renal flare. Immunosuppressive treatment was withdrawn in 35 (62.5%) patients and maintained/switch in 21 (37.5%). Afterwards, new renal flare occurred in 9 patients per group (25.7% and 43%, respectively), after a median time of 39 [6.5–55] months and 7 [6–30] months, respectively. There was no difference in the number of patients who developed chronic kidney disease (n = 14, 25%) according to the treatment. In conclusion, KB2 provides valuable information to guide the immunosuppressive maintenance therapy.

Microvascular C5b-9 deposition in non-lesional skin in patients with SLE and its correlation with active lupus nephritis: a prospective observational study

“…One study recently showed that despite reaching a perceived clinical remission by laboratory tests, 19.6% of patients had persistent activity on repeat renal biopsy. 19 This demonstrates the importance of finding alternative biomarkers of LN activity that can readily be used by physicians in everyday practice.…”

Kidney Biopsy in Management of Lupus Nephritis: A Case-Based Narrative Review

“…Studies of repeat kidney biopsies performed after the initial therapy have demonstrated a discordance between clinical and histological responses ( Fig 2 ). 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 In the studies by Malvar et al 54 and Zickert et al, 55 where the histological response was defined as an activity index of 0 points by 6 to 8 months after the commencement of the initial immunosuppressive therapy, 18% (5/28) and 71% (12/17) of patients with complete response still had histological evidence of active kidney inflammation, respectively. Histological evidence of ongoing active kidney inflammation was observed in 20% (8/41) and 39% (7/18), respectively, of patients with partial response.…”

Flares in Lupus Nephritis: Risk Factors and Strategies for Their Prevention

“…Monitoring of LN is done primarily on clinical grounds; however, there is often discordance between urinalysis, serological markers, and the underlying kidney histology [ 66 ]. In a cohort of 51 patients with complete renal response who underwent a second biopsy, residual low-grade histological activity (NIH activity index [AI] ≥ 2) was revealed in 11 (19.6%) [ 67 ]. In these patients, subsequent renal exacerbations were more frequent and occurred at an earlier time point as compared to their counterparts with AI < 2.…”