Hereditary Myelopathies

Etiological profile of noncompressive myelopathies in a tertiary care hospital of Northeast India

Background:

The discovery of antibodies against aquaporin-4 and evolving concepts of noncompressive myelopathies in the 21^st century have made a major impact on the etiological profile of these diseases, with few cases turning out to be idiopathic.

Objective:

To find causes of noncompressive myelopathy in a tertiary care hospital of Northeast India.

Materials and Methods:

An observational study was carried out in the Neurology Department of Gauhati Medical College, Guwahati, from September 2013 to February 2016. Patients of noncompressive myelopathies who underwent magnetic resonance imaging (MRI) of the spine were segregated into two categories: acute-to-subacute myelopathy (ASM) and chronic myelopathy (CM). In addition to routine blood tests, chest X-ray, urinalysis, and visual evoked potentials, investigations included MRI of the brain, cerebrospinal fluid analysis, and immunological, infectious, and metabolic profile based on the pattern of involvement.

Results:

The study had 151 patients (96 ASM and 55 CM) with a median age of 35 years and male: female ratio 1.4:1. The causes of ASM were neuromyelitis optica spectrum disorder (23), multiple sclerosis (MS) (8), systemic lupus erythematosus (1), Hashimoto's disease (1), postinfectious acute disseminated encephalomyelitis (6), postinfectious myelitis (8), infections (9), spinal cord infarct (5), and electrocution (1). The causes of CM were MS (1), probable or possible sarcoidosis (7), mixed connective tissue disease (1), Hashimoto's disease (2), infections (9), Vitamin B₁₂ deficiency (4), folate deficiency (2), hepatic myelopathy (2), radiation (11), and paraneoplastic (1). No etiology could be found in 48 (31.8%) patients (34 ASM and 14 CM). In 21/96 (21.9%) patients of ASM, acute transverse myelitis was idiopathic based on current diagnostic criteria.

Conclusion:

Underlying etiology (demyelinating, autoimmune, infectious, vascular, metabolic disorder, or physical agent) was found in 68% patients of noncompressive myelopathy.

Novel mutation in the ATL1 with autosomal dominant hereditary spastic paraplegia presented as dysautonomia

SPG3A, which is the second most common type of autosomal dominant hereditary spastic paraplegia (HSP), is caused by mutations in the atlastin GTPase 1 gene, ATL1. We report a case of a patient who presented as dysautonomia and had a novel splicing mutation c.35-3C>T in exon 2 of the ATL1. Orthostatic intolerance, urinary symptoms, hyperreflexia in the biceps and knee jerk, and decreased proprioception in both limbs were observed on neurological examinations. We tested the autonomic function and performed genetic tests for the SPG4 and SPG3A forms of HSP. This case is a genetically confirmed HSP with a novel mutation in SPG3A, and extends the phenotype of SPG3A.