Facebook Pixel Code
Brainworks image
BrainWorks

Demyelinating Diseases

Acute Disseminated Encephalomyelitis

  • Acute disseminated encephalomyelitis (ADEM) is an inflammatory demyelinating disease, characterized by an acute onset of central nervous system (CNS) deficits.
  • ADEM occurs with a temporal, and a suspected causative relationship to viral diseases, as well as to preventive vaccinations[4].
  • This disorder is generally monophasic and 70 per cent of patients show a full recovery[1].
  • Common symptoms seen in children with ADEM are meningism, fever and seizures[3]. As well, isolated transverse myelitis, the inflammation of a spinal cord segment along its width, is often seen in ADEM patients[2].
  • There is no single test confirming the diagnosis of ADEM, and diagnosis is based upon a combination of clinical and radiological features and the exclusion of diseases that resemble ADEM[5].  
  • Therefore, a broad workup including infectious, immunologic, and metabolic tests, as well as a systematic follow-up Magnetic Resonance Imaging (MRI) is needed to establish an accurate diagnosis[5].
  • There are two rare groups of relapsing ADEM events called multiphasic and recurrent ADEM[2].
    • The former episode involves a different lesion in the CNS and the latter is associated with repeating ADEM symptoms from the initial lesion. The follow-up MRI imaging shows a complete or close to full recovery of the lesion and no new lesions occur in the CNS[4].
  • The treatment for ADEM is intravenous corticosteroids and oral prednisone (if lesions are still present)[5]. Intravenous immunoglobulin can be implemented if the corticosteroids fail[5].

References:

  1. Banwell B, Ghezzi A, Bar-Or A, Mikaeloff Y, Tardieu M. Multiple sclerosis in children: clinical diagnosis, therapeutic strategies, and future directions. Lancet Neurol, 2007. 6(10): p. 887-902.
  2. Dale RC, Brilot F, Banwell B. Pediatric central nervous system inflammatory demyelination: acute disseminated encephalomyelitis, clinically isolated syndromes, neuromyelitis optica, and multiple sclerosis. Curr Opin Neurol, 2009. 22(3): p. 233-40.
  3. Neuteboom RF, Boon M, Catsman Berrevoets CE, Vles JS, Gooskens RH, Stroink H, Vermeulen RJ, Rotteveel JJ, Ketelslegers IA, Peeters E, Poll-The BT, De Rijk-Van Andel JF, Verrips A, Hintzen RQ. Prognostic factors after a first attack of inflammatory CNS demyelination in children. Neurology, 2008. 71(13): p. 967-973.
  4. Wender M. Acute disseminated encephalomyelitis (ADEM). J Neuroimmunol, 2011. 231(1-2): p. 92-9.
  5. Pohl D, Tenembaum S. Treatment of acute disseminated encephalomyelitis. Curr Treat Options Neurol, 2012. 14(3): p. 264-75.
  6. Brenton JN, Rust Jr RS. Acute Disseminated Encephalomyelitis. Medscape Reference. Web. 26 June 2012. < http://pandasnetwork.org/research/parent-research/fact-sheet/

Multiple Sclerosis

  • Multiple Sclerosis (MS) in children is a demyelinating disorder which can be caused by genetic or environmental triggers[1].
  • MS is defined as two or more CNS inflammatory demyelinating events that occur at least four weeks apart from each other[2].These events are confirmed on Magnetic Resonance Imaging (MRI) and seen through reoccurring symptoms.
  • Diagnosing MS in a child is complicated by the limited diagnostic criteria and the possibility of significant clinical and MRI overlap with other inflammatory brain diseases[3].
  • Common symptoms are: ataxia, optic neuritis, motor, sensory, and brainstem dysfunction[1].
  • Oligoclonal banding has been seen in more than 90 per cent of children with MS in a German study[1].
  • Standard treatment involves immunosuppressive corticosteroid therapy along with methylprednisone by IV or high dose oral prednisone during an acute relapse.

References:

  1. Banwell B, Ghezzi A, Bar-Or A, Mikaeloff Y, Tardieu M. Multiple sclerosis in children: clinical diagnosis, therapeutic strategies, and future directions. Lancet Neurol, 2007. 6(10): p. 887-902.
  2. Dale RC, Brilot F, Banwell B. Pediatric central nervous system inflammatory demyelination: acute disseminated encephalomyelitis, clinically isolated syndromes, neuromyelitis optica, and multiple sclerosis. Curr Opin Neurol, 2009. 22(3): p. 233-40.
  3. Pediatric Multiple Sclerosis. The Cleveland Clinic. Web. 26 June 2012. < http://pandasnetwork.org/research/parent-research/fact-sheet/>.

Optic Neuritis

  • Optic neuritis is an inflammatory, demyelinating condition that affects the optic nerve.
  • It can present as a result of idiopathic, systemic, or infectious origins.
  • It is highly associated with multiple sclerosis, and occurs in approximately 50 per cent of patients at some time during their disease course[2].
  • Many different conditions have been associated with causing optic neuritis, including:
    • Autoimmune diseases, such as multiple sclerosis and systemic lupus ertythematosus.
    • Bacterial infections, such as tuberculosis, syphilis, Lyme disease, and meningitis.
    • Viral infections, such as viral encephalitis, measles, rubella, chickenpox, herpes zoster, mumps, and mononucleosis.
  • Symptoms include[1,2]:
    • Monocular vision loss over a period of hours to days.
    • An afferent pupillary defect.
    • Loss of color vision.
    • Pain during eye movement.
  • The diagnosis of optic neuritis is made on clinical grounds, supplemented by ophthalmologic examination findings. However, in atypical cases, Magnetic Resonance Imaging (MRI) is used for more information and to exclude other diseases from consideration[1,2].  
  • Optic neuritis is treated with immunosuppressive corticosteroid therapy.
  • Treatment with high-dose corticosteroids may accelerate visual recovery, but has little impact on long-term visual outcome[1,2].
  • The outcome depends on the treatment of the underlying etiology causing the condition.

References:

  1. Shams PN, Plant GT. Optic neuritis: a review. Int MS J, 2009. 16(3): p. 82-9. 
  2. Brass SD, Zivadinov R, Bakshi R. Acute demyelinating optic neuritis: a review. Front Biosci, 2008. 13(1): p. 2376-90.
  3. Optic Neuritis. Queen's University - Department of Ophthalmology. Web. 31 May 2012. <http://ophthalmology.queensu.ca/>

Neuromyelitis optica

  • Neuromyelitis optica (NMO) is an inflammatory, demyelinating condition that affects the Central Nervous System, primarily the optic nerves and spinal cord and is characterized by a frequent relapses and disease flairs[1].
  • It is of unknown etiology, but is more common in people of African and Asian origin[4].
  • Serum IgG antibodies have been identified as the major cause of the inflammation, with the water channel aquaporin-4 (AQP4) as their main target antigen[1,2,4].
  • Diagnosis is made based on Magnetic Resonance Imaging (MRI) findings (normal brain MRI longitudinally extensive lesions on spinal cord MRI), and cerebrospinal fluid analysis (polymorphonuclear pleocytosis and absence of oligoclonal banding)[1,3].
  • The serum auto-antibody AQP4 antibodies/NMO-IgG is highly specific for the disorder and is a moderately sensitive serum biomarker for NMO[1,2,4].
  • This antibody is present in about 70 per cent of those with NMO and is not found in people with multiple sclerosis or other similar conditions[1,4].
  • The symptoms of NMO include those of optic neuritis and transverse myelitis. The symptoms of optic neuritis and transverse myelitis may occur monophasically or relapsing. When they are monophasic, symptoms of optic neuritis and myelitis tend to occur close to each other or even at the same time. When relapsing they can occur at intervals over years[4].
  • Other less common symptoms of NMO include vertigo, facial numbness, headache, and tremors[4].
  • Corticosteroids are the best therapeutic options for reducing the immune response during disease flairs. Rituximab and Mofetil Mycophenolate are also used to target and decrease autoantibody production[1].

References:

  1. Matà S, Lolli F. Neuromyelitis optica: an update. J Neurol Sci, 2011. 303(1-2): p. 13-21.
  2. Asgari N, Owens T, Frøkiaer J, Stenager E, Lillevang ST, Kyvik KO. Neuromyelitis optica (NMO) – an autoimmune disease of the central nervous system (CNS). Acta Neurol Scand, 2011. 123(6): p. 369-84.
  3. Nandhagopal R, Al-Asmi A, Gujjar AR. Neuromyelitis optica: an overview. Postgrad Med J, 2010. 86(1013): p. 153-9.
  4. Neuromyelitis Optica. The Cleveland Clinic. Web. 27 June 2012. < http://my.clevelandclinic.org/disorders/neuromyelitis_optica_nmo/ns_overview.aspx >.

Acute transverse myelitis

  • Acute Transverse Myelitis (ATM) is an inflammatory demyelinating disorder of the spinal cord, leading to motor, sensory and neurological dysfunction[2,4].
  • This disorder is of a heterogeneous pathology, with many different etiologies, including infections, inflammatory, malignant, and metabolic, but a substantial amount of cases remain idiopathic. The different types of ATM lead to different clinical presentation and outcome[3]
  • The diagnosis of ATM is considered when patients develop subacute spinal cord symptoms, and diagnostic imaging does not show compression of the spinal cord (such as a herniated disk)[5].
  • Magnetic Resonance Imaging (MRI) often shows a long segment of altered signal in the spinal cord which extends multiple segments along the spinal cord, illustrating demyelination and nerve injury. The cerebrospinal fluid (CSF) usually shows an increase in white blood cells. Patients with ATM usually do not have oligoclonal banding, which is relatively common in multiple sclerosis and other disorders[5].
  • Symptoms include back pain, numbness, tingling, and weakness in the legs, trunk and/or arms, and trouble with bowel and bladder function[5].
  • The recent identification of the NMO-IgG antibody, a new marker of neuromyelitis optica spectrum disorders (including ATM), has contributed to an evolving understanding of acute transverse myelitis[1,2,4].
  • Treatment involves corticosteroids to reduce the immune response and also plasmapheresis to remove the antibodies from the circulation[5].

References:

  1. Pittock SJ, Lucchinetti CF. Inflammatory transverse myelitis: evolving concepts. Curr Opin Neurol, 2006. 19(4): p. 362-8.
  2. Pandit L. Transverse myelitis spectrum disorders. Neurol India, 2009. 57(2): p. 126-33.
  3. Sá MJ. Acute transverse myelitis: a practical reappraisal. Autoimmun Rev, 2009. 9(2): p. 128-31.
  4. Borchers AT, Gershwin ME. Transverse myelitis. Autoimmun Rev, 2012. 11(3): p. 231-48.
  5. Transverse Myelitis. The Cleveland Clinic. Web. 27 June 2012. < http://my.clevelandclinic.org/disorders/transverse_myelitis/ns_overview.aspx>

Back to Top