Clinical presentation, outcomes and risk of relapses of lupus podocytopathy in a multicentre Italian cohort.

BACKGROUND

In an Italian cohort of lupus podocytopathy patients, we aimed to characterize the presenting features, therapy, and outcomes, and explore differences between relapsing and non-relapsing patients.

METHODS

We identified 29 patients with lupus podocytopathy from 1994 to 2023 in 11 Italian Nephrology/Rheumatology Units, and divided them into two groups: relapsing and non-relapsing. Given the limited sample size, a p-value ≤ 0.2 was considered as significant.

RESULTS

The median age of the patients was 43 (25-52) years, 89.7% were females, 89.6% presented with nephrotic syndrome, 34.4% with acute kidney dysfunction, and 44% with arterial hypertension. After corticosteroids and/or immunosuppressive therapy, complete (25 patients) or partial remission (4 patients) occurred within a median of 4 (1-9) months. Nine patients (31%) relapsed. After a further course of therapy, remission was achieved within 5 (2-11) months. Relapsing patients had higher serum creatinine (0.94 [0.73-2.65] vs 0.8 [0.6-1.1] mg/dl; p = 0.12), lower estimated glomerular filtration rate (76 [32.5-107.5] vs 93 [59.3-109.7] ml/min/1.73m; p = 0.23) and higher proteinuria (7.7 [5.9-11.7] vs 6.5 g/day [3.2-10.1]; p = 0.14) at lupus podocytopathy diagnosis than non-relapsing subjects. Activity indexes at biopsy were higher [(1 (0-2) vs 0 (0-1); p = 0.08] and cutaneous systemic lupus erythematosus manifestations were more prevalent (44.4% vs 10.5%; p = 0.06) in relapsing patients. After an observation of 49 (18-23) months, 86.2% of patients were in complete remission while 13.8% remained in partial remission. One patient developed mild chronic kidney function impairment.

CONCLUSIONS

Lupus podocytopathy typically presents with nephrotic syndrome and kidney dysfunction, it responds favourably to treatment, and generally results in a favourable renal outcome. We observed that more active renal and extrarenal lupus manifestations at the onset of lupus podocytopathy were indicative of higher susceptiblity to disease recurrence.