Rituximab for refractory focal segmental glomerulosclerosis

Area of Science:

• Pediatric Nephrology
• Immunology
• Oncology Therapeutics

Background:

• Steroid-resistant nephrotic syndrome (SRNS) presents a significant therapeutic challenge in pediatric patients.
• Focal segmental glomerulosclerosis (FSGS) is a common histopathological finding in SRNS, often associated with poor prognosis.
• Conventional treatments, including steroids and plasmapheresis, can be limited by severe adverse effects and variable efficacy.

Observation:

• Two pediatric patients with biopsy-proven FSGS and SRNS were refractory to standard therapies.
• Initial management involved combination therapy with methylprednisolone pulse and plasmapheresis, achieving only temporary proteinuria reduction but causing severe steroid-related complications.
• Rituximab (anti-CD20 monoclonal antibody) was administered as a single dose (375 mg/m(2)) to both patients, leading to rapid depletion of circulating CD19-positive B cells.

Findings:

• Both patients achieved partial remission within one month post-rituximab treatment.
• One patient maintained complete remission for 8 months, while the other experienced a relapse at 8 months coinciding with B-cell recovery, necessitating a second rituximab course.
• The second rituximab treatment led to complete remission sustained for at least 2 months, suggesting potential for sustained B-cell targeted therapy.

Implications:

• Rituximab may represent a viable and effective therapeutic option for pediatric SRNS with FSGS, particularly in cases resistant to or intolerant of conventional treatments.
• B-cell depletion via anti-CD20 therapy could be a key mechanism in achieving and maintaining remission in this challenging condition.
• Further investigation and larger studies are warranted to confirm the efficacy, optimal dosing, and long-term safety of rituximab in pediatric SRNS.