Abstract General Information

Title

Concomitant multiple sclerosis and idiopathic thrombocytopenic purpura treated with ocrelizumab

Case Report

A 24-year-old female patient was diagnosed with idiopathic thrombocytopenia purpura (ITP) at age 11 (2009) and evolved with frequent ITP exacerbations, some of them requiring hospitalization. From childhood until 2020 she underwent total splenectomy (2009) and received different treatments: corticosteroids, immunoglobulin, cyclophosphamide, azathioprine, 4 doses of rituximab (last infusion in 2010). At age 22 (October 2020) she noticed left hemihypoesthesia during an episode of ITP exacerbation (gynecological bleeding). Brain and spinal cord MRI showed typical multiple sclerosis (MS) lesions. The investigation showed positive oligoclonal bands, negative anti-aquaporin-4 antibody, and positive serology for the JC virus. While awaiting ocrelizumab, she presented right optic neuritis and MRI activity (December 2020). Ocrelizumab was started in March 2021 and since then, she remained on NEDA (no evidence of disease activity), with sustained B cells depletion. Soon after each ocrelizumab infusion, there was an temporary improvement on platelets levels. However, there were new episodes of ITP exacerbation (3 of which led to hospitalization), even with the use of eltrombopag (thrombopoietin receptor agonist) and anti-CD20. It was then decided to reintroduce azathioprine and maintain ocrelizumab, evolving with ITP remission since August 2022. As already described, MS has remained stable since the beginning of ocrelizumab.
DISCUSSION: ITP diagnosis is higher in MS patients compared to the general population. This association occurs mainly as drug-induced thrombocytopenia, especially under Alemtuzumab treatment (2.2%). There are reports of ITP induced by other MS treatments, but at a much lower frequency. The co-occurrence of spontaneous ITP and MS is less frequent. Previous splenectomy could also trigger additional immune dysregulation.
FINAL COMMENTS: This case illustrates the association of two autoimmune diseases, where anti-CD20 therapy was suitable to silence MS, but it was not enough to keep ITP in remission as monotherapy, requiring association with an oral immunosuppressant.