Clinicopathologic characteristics and outcomes of late onset lupus nephritis: a single centre experience.

ABSTRACT

Systemic Lupus Erythematosus (SLE) occurs in the reproductive age group. Renal involvement occurs less frequently in late-onset SLE than in reproductive-age SLE patients. Here, we aimed to study the clinical, serological and histopathological characteristics of late-onset lupus nephritis (LN). Late-onset LN was defined as disease onset after 47 years of age, corresponding to the average menopausal age. Records of biopsy proven late-onset lupus nephritis patients diagnosed between June 2000 and June 2020 were reviewed. Late-onset LN constituted 53 of 4420 patients (1.2%) biopsied during the study period. Females represented 90.65% of the cohort. Mean age of the cohort was 49.5 ± 7.05 years at the time of SLE diagnosis while its renal presentation was delayed by median duration of 10 months (IQR 3-48 months). Renal failure was present in 28 patients (52.8%) with acute kidney injury (AKI) (28.3%, n = 15) as the most common presentation. On histopathological analysis, class IV was observed in 23 patients (43.5%), crescents were observed in one-third cases and lupus vasculopathy in 4 patients (7.5%). All patients received steroids. Majority of patients (43.3%; n = 23) received Euro lupus protocol for induction. On median follow up duration of 82 months, renal flares were noted in 9 patients (17%) and 8 patients (15.1%) became dialysis dependent. Among 11 patients (21%) with infectious complications, 7 patients (13.2%) suffered from tuberculosis. Infections caused three-fourth of the deaths. Late-onset lupus nephritis is rare and presents as renal failure in majority. Renal biopsy affects the clinical decision of judicious use of immunosuppression which is imperative due to high rate of infections in this cohort.