Demyelinating diseases consists of a group of disorders characterized by the loss of myelin with relative axonal sparing. Primary demyelinating disorders may be attributed to autoimmune mechanisms. Demyelination is often secondary to infectious, metabolic, ischemic, or hereditary disorders or exposure to a toxin.
Presentation
Symptoms of demyelinating disorders are variable and depend on the neurologic deficits in the affected portion of the nervous system. Primary demyelinating disorders should be considered in patients presenting with diffuse or multifocal neurologic deficits of acute onset that wax and wane; in particular those that onset shortly after a vaccination or infection. The most common presenting symptom of demyelinating diseases are sensory disturbances of the limbs, vision loss, and subacute motor symptoms (e.g, weakness, spasticity, hyperreflexia, gait and balance disturbance) [1].
Common demyelinating disorders and presenting symptoms include:
- Multiple sclerosis - Common presenting features of multiple sclerosis include weakness, paraesthesia or focal sensory loss, diplopia, optic neuritis, ataxia, dizziness, muscle spasms, trigeminal neuralgia, depression, weakness, fatigue, seizures, and/or mild cognitive impairment. Bladder, bowel, and sexual dysfunction often occur as well [2].
- Acute disseminated encephalomyelitis - Patients with acute disseminated encephalomyelitis commonly have ataxia, headache, weakness, slurring of words, speech impairment, cranial nerve palsies, seizures, lethargy, delirium, stupor, and/or vomiting [3] [4].
- Progressive multifocal leukoencephalopathy - Common symptoms of progressive multifocal leukoencephalopathy include insidious onset of neurological deficits related to speech, vision, motor function, personality, and cognition [5] [6].
- Central pontine and extrapontine myelinolysis is characterized by acute onset of confusion, weakness of the extremities, and/or mutism. Other symptoms may include ataxia, difficulty swallowing, and low blood pressure. Some patients may also complain of movement disorders (e.g., dystonia, choreoathetosis, shuffling).
Urogenital
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Pelvic Pain
Pelvic pain as the presenting symptom of demyelinating disease is rare. We report on a 49-year-old female patient that initially had symptoms of pain and anesthesia in the perineum. [ncbi.nlm.nih.gov]
Neurologic
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Myokymia
Facial myokymia must raise the possibility of MS in adults under the age, of 40. [ncbi.nlm.nih.gov]
[…] can generate action potentials denovo in the axon and may explain Lhermitte’s phenomenon ( Electric shock like sensation on flexing the neck) Spontaneous action potentials are thought to cause paroxysmal positive symptoms such as trigeminal neuralgia, myokymia [slideshare.net]
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Spastic Gait
We describe herein the case of a 57 year old man who, over the last five years, has presented ataxic and spastic gait on the right side, a reduction in fine motor movement of the fingers mainly on the right side, superficial right side brachiocrural hypoesthesia [ncbi.nlm.nih.gov]
On first evaluation she had an atrophic optic disc on the left side, mild spastic gait and increased muscle stretch reflexes. [scielo.br]
Workup
The diagnosis of demyelinating disease consists of a history of present illness, physical exam, laboratory, neuromuscular and imaging tests. A history of any recent infections and/or vaccinations should be noted.
Laboratory tests that should be done include complete blood count, syphilis test (e.g., RPR), antinuclear antibodies, fluorescent treponemal antibody test, lyme titer, sedimentation rate, and angiotensin converting enzyme level [7].
A cerebrospinal fluid (CSF) exam may demonstrate pleocytosis (slight elevation of mononuclear white blood cells), oligoclonal immunoglobulin G (IgG) bands, and an elevated globulin to albumin ratio [8]. Patients with myelin damage will have elevated CSF myelin protein levels, which is indicative of myelin damage.
A magnetic resonance imaging (MRI) scan may show subclinical demyelinated lesions and/or enhancement of nerve roots with the use of gadolinium [9].
The "hot bath test" works by elevating the body's temperature, which leads to exacerbation of symptoms and worsened deficits in persons with demyelinating disease.
Neuromuscular testing including an electromyography (EMG) can be used to help determine presence of peripheral neuropathy and demyelination [10].
A sural nerve biopsy can be performed to add to the evidence for the diagnosis of a demyelinating disease.
MR
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Brain MRI Abnormal
Brain MRI abnormalities were found in only 5 (29%) of these patients, and they were asymptomatic in 3 cases ( figures 3 and 4 ). [nn.neurology.org]
Radiologically isolated syndrome (RIS) affects patients who have incidental brain MRI abnormalities suggestive of MS, but without any sign or symptom attributable to the disease. [jcsm.aasm.org]
Other Test Results
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Slow Nerve Conduction Velocities
Tests that can be of diagnostic help include nerve conduction testing and electromyography looking for very slow nerve conduction velocities, lumbar puncture looking for elevated spinal fluid protein without many inflammatory cells and MRI imaging of [rarediseases.org]
Other Pathologies
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Intranuclear Inclusion Bodies
Measles virus intranuclear inclusion bodies may be seen, but tend to be sparse. In most cases the clinical and serological findings are diagnostic, and viral RNA can be detected by PCR. [ncbi.nlm.nih.gov]
Treatment
Carroll WM 1, Saida T, Kim HJ, Kira J, Kermode AG, Tsai CP, Fujihara K, Kusunoki S, Tanaka M, Kim KK, Bates D ; Pam-Asian Committee on Treatment and Research of Multiple Sclerosis. [ncbi.nlm.nih.gov]
Prognosis
Prognosis of Demyelinating Diseases Prognosis of Demyelinating Diseases depends on the condition. [epainassist.com]
Demyelinating Disease Prognosis The outcome of treatment depends on what type of demyelinating disorder is present in the patient. [hxbenefit.com]
Clinicopathologic findings and prognosis of chronic inflammatory demyelinating polyneuropathy. Neurology. 1999;52:498-503. Lewis RA. Multifocal motor neuropathy and Lewis Sumner syndrome: two distinct entities. Muscle Nerve. 1999;22:1738-39. Nevo Y. [rarediseases.org]
Etiology
Abstract Immune mediated demyelinating disease (IMDD) after allogeneic hemopoietic stem cell transplant (HSCT) is rare and its etiology unclear. [ncbi.nlm.nih.gov]
Epidemiology
The first (UCID-SS) is an epidemiological surveillance study that already received ethical approvals, and started on the 1st September 2009. [ncbi.nlm.nih.gov]
Pathophysiology
This review discusses clinical, pathophysiological, radiological and therapeutic concepts of demyelinating disease of the CNS in SLE, focussing on its differentiation from MS and its relation with other CNS demyelinating processes, such as transverse [ncbi.nlm.nih.gov]
Cause & pathophysiology Cause- exactly not known Genetic propensity- HLA-DR15 & DQ6 increase risk Infection- possible trigger of inflammatory response- HHV, MMR Other- decreased sunlight exposure, smoking, stress, vaccinations, toxins Pathophysiology [slideshare.net]
Various autoimmune diseases, including the following, can damage the myelin sheath: Devic’s Disease Schilder’s Disease Fibromyalgia Guillain-Barre Syndrome Demyelinating Disease Pathophysiology Doctors still do not know the exact mechanism of nerve demyelination [hxbenefit.com]
Prevention
Treatment Aims- returning function after an acute attack, preventing new attacks, preventing disability Acute attack- IV methylprednisolone plasmapheresis Disease modifiers- Interferon β-1a/1b Glatiramer Mitoxantrone Natalizumab Supportive [slideshare.net]
However, it cannot be prevented in individuals with genetic factors causing nerve demyelination. Researches are being carried out to find out whether it is possible to prevent nerve demyelination in such people. [hxbenefit.com]
Cells/immunology Dendritic Cells/metabolism Dendritic Cells/pathology Disease Models, Animal Encephalomyelitis, Autoimmune, Experimental/immunology* Encephalomyelitis, Autoimmune, Experimental/microbiology Encephalomyelitis, Autoimmune, Experimental/prevention [ncbi.nlm.nih.gov]
Treatment of multiple sclerosis can be discussed in terms of the management of acute relapses, the prevention of relapses as modification of the disease process, and the management of symptoms and fixed neurologic deficits. [streetdirectory.com]
References
- Olek, 2005 - adapted from Paty et al., 1994 and Studney D et al., 1993, MS COSTAR: A computerized patient record adapted for clinical research purposes. J Neurol Rehab; 7:145.
- McAlpine D, Lamsden CE, Acheson ED. Multiple Sclerosis - A Reappraisal, ed. 2, Edinburgh, Churchill and Livingstone, 1972.
- Gupte G, Stonehouse M, Wassmer E, et al. Acute disseminated encephalomyelitis: a review of 18 cases in childhood. J Paediatr Child Health. 2003;39:336–42
- Leake JA, Albani S, Kao AS, et al. Acute disseminated encephalomyelitis in childhood: epidemiologic, clinical and laboratory features. Pediatr Infect Dis J. 2004;23:756–64.
- Sugimoto C, Ito D, Tanaka K, et al. Amplification of JC virus regulatory DNA sequences from cerebrospinal fluid: diagnostic value for progressive multifocal leukoencephalopathy. Arch Virol 1998;143:249–62.
- Hammarin AL, Bogdanovic G, Svedhem V, et al. Analysis of PCR as a tool for detection of JC virus DNA in cerebrospinal fluid for diagnosis of progressive multifocal leukoencephalopathy. J Clin Microbiol 1996;34:2929–32.
- Jones CT. Childhood autoimmune neurologic diseases of the central nervous system. Neurol Clin. 2003;21:745–64.
- Park SJ, Jeong IH, Kong BS, et al. Disease Type- and Status-Specific Alteration of CSF Metabolome Coordinated with Clinical Parameters in Inflammatory Demyelinating Diseases of CNS. PLoS One. 2016;11:e0166277.
- Balashov K. Imaging of Central Nervous System Demyelinating Disorders. Continuum (Minneap Minn). 2016 Oct;22(5, Neuroimaging):1613-35.
- Hanewinckel R, Ikram MA, Van Doorn PA. Peripheral neuropathies. Handb Clin Neurol. 2016;138:263-82.