Optic neuritis (ON) is an acute inflammatory process of the optic nerve, and it is rare at pediatric age. However, ON occurs in approximately a quarter of children who have an initial demyelinating event. There are few studies of pediatric ON.
To perform a retrospective analysis of patients with ON followed at neuropediatric consultation in a Tertiary Pediatric Center (Centro Hospitalar Universitário do Porto).
Patients with ON followed in the neuropediatrics consultation, from 2014 to 2019, were identified and a descriptive analysis was performed based on their clinical records.
Ten patients with ON were included. Their final diagnosis were multiple sclerosis (MS) in four patients, neurosarcoidosis in two patients, anti-MOG syndrome in one patient, anti-NMDA encephalitis in one patient, HIV encephalopathy in one patient and an ON in study in one patient. Four (40%) were female and the mean age at diagnosis was 12.7 years old (6-17 years old). All patients had decreased visual acuity at presentation, half (50%) with bilateral involvement, and half (50%) with dyschromatopsia. Headache / retrocular pain was described in eight (80%) patients. Seven (70%) patients had a normal remaining neurological examination. The average duration of hospitalization was 7 days. Half (50%) of the patients had oligoclonal bands in cerebrospinal fluid.
Brain MRI showed no major changes in three (30%) and demyelinating lesions in six (60%) patients. All patients performed methylprednisolone (3-5 days) with eight (80%) fully recovering their vision, one presenting subjective complaints of decreased visual acuity with exercise. For long-term treatment, the patient with aseptic meningitis secondary to neurosarcoidosis is under infliximab. Among the 4 patients with MS criteria, two started treatment with natalizumab and the other two with pegylated interferon beta.
In this series of patients who had ON five (50%) had demyelinating Central Nervous System (CNS) disease. Accordingly, to the literature, between 13% and 36% of children with an initial episode of ON are diagnosed with MS after a short follow-up period. Since this is a retrospective study in neuropediatrics consultation directed to demyelinating diseases, there is a selection bias that may explain the results found. However, it should be noted that even the most frequent etiologies in this age group (infection, immunization) were not found with the expected frequency. With this work, we would also like to raise awareness for the importance of risk stratification of CNS demyelinating disease in children with ON.