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Enterovirus Encephalitis in People With Multiple Sclerosis on Ocrelizumab: Insights From a Multicenter Case Series
Samantha A Banks1,2, Ilia Poliakov3, Eoin P Flanagan1,2,4
1Department of Neurology, Mayo Clinic, Rochester, MN.
Objectives:
Anti-CD20 therapies for multiple sclerosis (MS) are highly effective at preventing disease activity. Recognizing infectious complications of these therapies is essential.
Methods:
Three MS centers shared deidentified clinical data on persons with MS (pwMS) receiving ocrelizumab who developed enterovirus encephalitis.
Results:
Five pwMS (4 with relapsing-remitting MS, 1 with secondary progressive MS) on ocrelizumab were identified. At diagnosis, the median age was 34 years (range, 30-57), the median MS duration was 5 years (range, 2-13), and the median ocrelizumab exposure was 3 years (range, 2-7). Four had young children who were recently ill, including 2 with hand, foot, and mouth disease. MRI brain revealed new nonenhancing T2 hyperintensities in the thalamus (2), substantia nigra (2), cerebellum (2), and pons (1). All had CSF pleocytosis (median, 57/mcL; range, 33-175). Enterovirus was detected by reverse-transcription PCR in CSF (4) and blood (2). Hypogammaglobulinemia was present in 4 patients tested; 1 also had neutropenia. Three received IV immunoglobulin. At follow-up (median, 7 months; range, 3-15), 1 patient had fully recovered and 4 had residual symptoms (cognitive, 1; gait impairment, 3).
Discussion:
Enterovirus encephalitis is a rare but serious complication in pwMS receiving ocrelizumab; hypogammaglobulinemia may increase risk. Clinician awareness and prompt testing may improve outcomes.
Insights
Ocrelizumab for multiple sclerosis (MS) can rarely lead to enterovirus encephalitis. Hypogammaglobulinemia may increase risk, highlighting the need for clinician awareness and prompt diagnosis in MS patients.
Area of Science:
- Neurology
- Infectious Diseases
- Immunology
Background:
- Anti-CD20 therapies, like ocrelizumab, are effective for multiple sclerosis (MS).
- Recognizing and managing infectious complications associated with these therapies is crucial for patient safety.
- Enterovirus encephalitis is a potential, albeit rare, complication.
Purpose of the Study:
- To identify and characterize cases of enterovirus encephalitis in persons with MS (pwMS) treated with ocrelizumab.
- To understand the clinical presentation, diagnostic findings, and outcomes of this complication.
Main Methods:
- A retrospective review of deidentified clinical data from three MS centers.
- Inclusion criteria: pwMS receiving ocrelizumab who developed enterovirus encephalitis.
- Data collected included demographics, MS characteristics, ocrelizumab exposure, clinical presentation, MRI findings, CSF analysis, and outcomes.
Main Results:
- Five pwMS on ocrelizumab were identified with enterovirus encephalitis.
- Median age was 34, median MS duration 5 years, and median ocrelizumab exposure 3 years.
- Common findings included CSF pleocytosis, enterovirus detection in CSF/blood, and hypogammaglobulinemia in 4/4 tested patients. Residual symptoms were common (4/5 patients).
Conclusions:
- Enterovirus encephalitis is a rare but serious complication in pwMS treated with ocrelizumab.
- Hypogammaglobulinemia may be an associated risk factor.
- Increased clinician awareness and prompt diagnostic testing are essential for improved patient outcomes.
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