Background/Purpose: Small vessel childhood primary angiitis of CNS (SVcPACNS) is an increasingly recognized inflammatory brain disease requiring rapid targeted investigation and initiation of tailored therapies to prevent brain damage. Spinal cord involvement has never been systematically investigated. Objective: To determine the presenting clinical and laboratory features, neuroimaging, treatment and outcome of children with spinal cord involvement in SVcPACNS.

Methods: A single center cohort study of children with small vessel primary CNS vasculitis diagnosed between 2002 and 2016 was conducted. Children were included, if they were 1) age ≤18years, 2) met Calabrese criteria and 3) had evidence of spinal cord inflammation. Data were captured in the BrainWorks database. Outcome: Neurological function at 12 months was determined using the Pediatric Stroke Outcome Measure; secondary outcomes included the estimated disease activity and damage.

Results: A total of 158 children were diagnosed with primary CNS vasculitis; 52 (33%) were found to have SVcPACNS, of whom 20 had spinal cord imaging for clinical concerns. These were 13 girls and 7 boys; median age was 10.1 years (range 5.4-17.7). The median time from onset of symptoms to diagnosis was 57 days (range 10-1041). A total of 11 (55%) had evidence of spinal inflammatory lesions on MRI. Their clinical features at diagnosis included hemiparesis (13), visual impairment (10), optic neuritis (4) and status epilepticus (4). At diagnosis, 8/9 tested (89%) had abnormal serum inflammatory markers (ESR 6/9, CRP 3/9) or vWF antigen (3/7, 42%). Raised CSF cell count was seen in 7/9 (78%). Imaging: 21 lesions were detected; the spinal lesion load was 1.9 per patient. Distribution: Nine lesions were located in the cervical, 10 in the thoracic and 2 in the lumbar spine. 17 lesions (81%) were long segments (> 3 vertebrae). Gadolinium enhancement was seen in 7/9 (78%), cord swelling in 3/11 (27%). All children were treated with the BrainWorks SVcPACNS protocol. Outcome: A total of eight patients (73%) had a no functional neurological deficit at 12 months. The median disease activity was 3/10 (range 0.5-8) and estimated disease damage 1/10 (range 0.1-3) at 12 months.

Conclusion: One in five children with brain biopsy confirmed primary CNS vasculitis had symptomatic spinal cord inflammation. The differential diagnosis of myelitis should include SVcPACNS. Rapid diagnosis and targeted therapy may improve the outcome.