Rituximab Treatment Outcomes in Children with Steroid-Resistant Nephrotic Syndrome

Abstract

Background: Idiopathic steroid-resistant nephrotic syndrome (SRNS) in children is often challenging to treat. Calcineurin inhibitors comprise the first-line induction therapy but have significant side effects. Children who fail to respond to treatment progress to end-stage renal disease (ESRD). The treatment protocol for refractory SRNS is not well established, but over the last decade, rituximab has been used successfully to treat these cases.

Objectives: To determine the efficacy and safety of rituximab for treating children with SRNS over a relatively long follow-up assessment period.

Patients and methods: A retrospective cohort study was conducted at King Saud Medical City, Riyadh, Saudi Arabia. All children with idiopathic SRNS who failed to achieve remission after 4 weeks of prednisolone 60 mg/m²/day were enrolled. All patients underwent renal biopsies and genetic studies before rituximab treatment. Intravenous rituximab was administered weekly at 375 mg/m² for four doses. Response to treatment was defined as maintaining remission with no relapse for 1 year.

Results: 21 patients (male: female = 15:6) were enrolled in the study and followed up for 1 year. Twelve (57.1%) patients showed no relapse in the first year, three (14.3%) developed only one relapse in the first year, and six (28.6%) had no remission, but three (50%) of these six patients developed ESRD and one (16.7%) of the six developed chronic kidney disease (CKD). The histopathological findings for the patients who responded to rituximab therapy (no relapse in the first 1 year) were as follows: Focal segmental glomerulosclerosis “FSGS” (25%), minimal change (66.7%), and renal biopsy were not performed in one patient because of logistic reasons. The histopathological findings for the patients who did not respond to rituximab therapy (no remission in the first year) were as follows: FSGS (83.3%) and diffuse change (16.7%). The four patients who developed ESRD/ CKD were in the FSGS category. No side effects from rituximab therapy were noted during the follow-up period.

Conclusion: Rituximab was effective and relatively safe for idiopathic SRNS, but large controlled clinical trials with long-term follow-up are required for confirmation.