Relapsing Demyelinating Syndromes in Children: A Practical Review of Neuroradiological Mimics

Abstract

Relapsing demyelinating syndromes (RDS) in children encompass a diverse spectrum of entities including multiple sclerosis (MS) acute disseminated encephalomyelitis (ADEM), aquaporin-4 antibody associated neuromyelitis optica spectrum disorder (AQP4-NMOSD) and myelin oligodendrocyte glycoprotein antibody disease (MOG-AD). In addition to these, there are "antibody-negative" demyelinating syndromes which are yet to be fully characterized and defined. The paucity of specific biomarkers and overlap in clinical presentations makes the distinction between these disease entities difficult at initial presentation and, as such, there is a heavy reliance on magnetic resonance imaging (MRI) findings to satisfy the criteria for treatment initiation and optimization. Misdiagnosis is not uncommon and is usually related to the inaccurate application of criteria or failure to identify potential clinical and radiological mimics. It is also notable that there are instances where AQP4 and MOG antibody testing may be falsely negative during initial clinical episodes, further complicating the issue. This article illustrates the typical clinico-radiological phenotypes associated with the known pediatric RDS at presentation and describes the neuroimaging mimics of these using a pattern-based approach in the brain, optic nerves, and spinal cord. Practical guidance on key distinguishing features in the form of clinical and radiological red flags are incorporated. A subsection on clinical mimics with characteristic imaging patterns that assist in establishing alternative diagnoses is also included.

MOG Antibody Disease Presenting as Multiphasic Disseminated Encephalomyelitis

“…Optic neuritis associated with MOG antibody is often longitudinally extensive and bilateral, involving the optic discs and sparing the optic chiasm. 1,2,3 The presence of MOG antibody, particularly persistent high titers, in children with an ADEM-like presentation increases the risk of a recurrent/relapsing course, as illustrated by this case. 2,3,4 Conflict of Interest None declared.…”

Child Neurology: Familial Hemophagocytic Lymphohistiocytosis Underlying Isolated CNS Inflammation

“…Imaging findings regarding HLH in the central nervous system range from normal findings, to nonspecific findings such as isolated cortical atrophy, to extensive parenchymal disease with multifocal white matter lesions with or without leptomeningeal and/or perivascular enhancement, with frequent cerebellar involvement (7,8,10,11). Tumefactive lesions, optic neuritis and spinal cord lesions have also been described (12). Malik et al grouped imaging patterns into two main groups: 1) parenchymal disease, and 2) normal or nonspecific findings, and subdivided the first group into: 1.1) multifocal cerebral/cerebellar lesions, 1.2) brainstem predominant pattern (CLIPPERS-like pattern), and 1.3) diffuse cerebellar involvement/cerebellitis (11).…”

NMOSD—Diagnostic Dilemmas Leading towards Final Diagnosis

“…This study found that underdiagnosis of NMOSD is still a common problem which may be associated with many factors. The literature describes cases of imitation of NMOSD by other diseases [ 20 , 21 ], also in children [ 22 ]. Perhaps, the complexity of the diagnostic process may be a problem as well as the long time period from the appearance of the first symptom to diagnosis of NMOSD, as has already been described for MS [ 23 , 24 ].…”