MR imaging in children with transverse myelitis and acquired demyelinating syndromes.

Background: Transverse myelitis (TM) occurs isolated or within other acquired demyelinating syndromes (ADS) such as neuromyelitis optica spectrum disorders (NMOSD), multiple sclerosis (MS) or myelin oligodendrocyte glycoprotein antibody associated disorders (MOGAD). Objective: To describe and compare clinical and MRI features of children with ADS presenting with TM grouped according to antibody status and diagnosis of MS and NMOSD. Patients and methods: Children with TM, radiological involvement of the myelon, MOG and aquaporin-4 antibody status were elegible. Results: 100 children were identified and divided into MOGAD (n=33), NMOSD (n=7), double seronegative TM (n=34), and MS (n=26). MOGAD children had mainly acute disseminated encephalomyelitis + TM/ longitudinally extensive TM (LETM) (42%) or isolated LETM (30%). In MOGAD, LETM was present in more than half of all children (55%) with predominant involvement of only the grey matter (73%). Leptomeningeal enhancement was highly predictive of MOGAD (16/30; p=0.003). In MS patients spinal MRI showed single (50%) or multiple short lesions (46%) with involvement of grey and white matter (68%). Double seronegative children presented with LETM (74%) and brain lesions were less frequent compared to the other groups (30%). Conclusion: Children with ADS presenting with TM reveal important radiological differences such as LETM with predominant involvement of spinal grey matter and leptomeningeal enhancement in MOGAD.