Classical Complement Pathway Inhibition in a Pediatric Patient With Refractory Immune Thrombocytopenia.

Pediatric refractory immune thrombocytopenia (rITP) is generally characterized by persistent thrombocytopenia and failure to achieve a sustained response to multiple standard therapies. We report a 4-year-old female with congenital tufting enteropathy, post-intestinal transplant patient on immunosuppressants, who developed severe rITP unresponsive to intravenous immunoglobulin, corticosteroids, rituximab, thrombopoietin receptor agonists, and vincristine. Complement inhibition with Berinert led to a rapid response, and sutimlimab led to sustained platelet recovery. This case highlights complement inhibition as a potential therapeutic option for rITP, representing the first reported pediatric case utilizing this approach for treatment-resistant pediatric ITP.