Pediatric demyelinating diseases

Clinical and Genetic Analysis in Pediatric Patients with Multiple Sclerosis and Related Conditions: Focus on DR Genes of the Major Histocompatibility Complex

Introduction:

There are several diseases recognized as variants of MS: post-infectious acute disseminated encephalitis, multiple sclerosis (MS), Rasmussen leukoencephalitis and Schilder's leukoencephalitis and related, but separate neuroimmune condition – Neuromyelitis Devic’s. In Kazakhstan diagnosis of such diseases was rare and immune modified treatment was only admitted after the age of 18. Clinical and immunogenetic study of MS spectrum diseases in Kazakhstan would allow to justify early targeted treatment.

Objective:

The aim of the study was to investigate genes of the main complex of human histocompatibility (MHC) associated with diseases of MS spectrum in Kazakhstani population.

Methods:

Complex clinical, neuroimaging and immunogenetic studies were performed in 34 children (24 girls, 10 boys) aged 4 to 18 years. 21 children were diagnosed with MS (11 Kazakh origin and 10 – Russian; 4 boys, 17 girls), 7 with leucoencephalitis (all Kazakh, 5 boys, 2 girls) and 6 with Devic neuromyelitis optica (all Kazakh, 1 boy, 5 girls). Genotyping of HLA DRB1, DQA1, DQB1 genes was performed for all patients.

Results:

MS group was characterized by classical relapsing-remitting MS. Predominant haplotype as a linkage complex was DRB1*15:01~DQA1*01:02~DQB1*06:02 in 20 (47.6%) of 42 DR-alleles, in 16 (76.2%) patients. MS relative risk (RR) was 13,36 for ethnic Kazakhs and RR=5,55 in Russians.

Leukoencephalitis had 7 children, with 28.6% mortality rate. The haplotype DRB1*15:01~DQA1*01:02~DQB1*06:02 as a linkage complex was detected 3 patients (4 alleles), RR=5,88.

Devic’s neuromyelitis optica (NMO) clinical course was characterized by fast and prolonged progression. There was predominance of DRB1*14 allele with RR=3,38.

Conclusion:

Summarizing, in the Kazakh population the haplotype DRB1*15:01∼DQA1*01:02∼DQB1*06:02 as a linkage complex was associated with prediction to MS and leukoencephalitis, but not to Devic’s NMO. Our study highlights the importance of awareness of MS and related disorders diagnosis which allows to implement early admission of disease-modified treatment in pediatric MS in Kazakhstan.

Acute Disseminated Encephalomyelitis: Current Perspectives

Acute disseminated encephalomyelitis (ADEM) is an immune-mediated central nervous system (CNS) disorder, characterized by polyfocal symptoms, encephalopathy and typical magnetic resonance imaging (MRI) findings, that especially affects young children. Advances in understanding CNS neuroimmune disorders as well as the association of myelin oligodendrocyte glycoprotein antibody (MOG-Ab) with both monophasic and recurrent forms of ADEM have led to new insights into its definition, management and outcome. In this review, we aim to provide an update based on current epidemiologic, clinical, radiological and immunopathological aspects and clinical outcome of ADEM.

Pain and spinal cord imaging measures in children with demyelinating disease

Pain is a significant problem in diseases affecting the spinal cord, including demyelinating disease. To date, studies have examined the reliability of clinical measures for assessing and classifying the severity of spinal cord injury (SCI) and also to evaluate SCI-related pain. Most of this research has focused on adult populations and patients with traumatic injuries. Little research exists regarding pediatric spinal cord demyelinating disease. One reason for this is the lack of reliable and useful approaches to measuring spinal cord changes since currently used diagnostic imaging has limited specificity for quantitative measures of demyelination. No single imaging technique demonstrates sufficiently high sensitivity or specificity to myelin, and strong correlation with clinical measures. However, recent advances in diffusion tensor imaging (DTI) and magnetization transfer imaging (MTI) measures are considered promising in providing increasingly useful and specific information on spinal cord damage. Findings from these quantitative imaging modalities correlate with the extent of demyelination and remyelination. These techniques may be of potential use for defining the evolution of the disease state, how it may affect specific spinal cord pathways, and contribute to the management of pediatric demyelination syndromes. Since pain is a major presenting symptom in patients with transverse myelitis, the disease is an ideal model to evaluate imaging methods to define these regional changes within the spinal cord. In this review we summarize (1) pediatric demyelinating conditions affecting the spinal cord; (2) their distinguishing features; and (3) current diagnostic and classification methods with particular focus on pain pathways. We also focus on concepts that are essential in developing strategies for the detection, monitoring, treatment and repair of pediatric myelitis.

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Pain is a major presenting symptom in children with myelitis.

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Currently used imaging has limited sensitivity to myelin content.

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We provide a summary on pediatric demyelinating conditions.

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We review pain involvement and pathways affected by demyelination.

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We review imaging modalities for the diagnosis and monitoring of myelitis.