DEMYELINATING DISEASES

1. DEMYELINATING DISEASES Prof. Abdulkader DAIF, MD King Khalid Univ.Hospital

2. DEMYELINATING DISEASES • Demyelinating diseases comprise a group of neurologic disorders • Focal or patchy destruction of myelin sheaths in the central nervous system accompanied by an inflammatory response

3. CALCIFICATION of Demyelinating disorders

5. Incidence and prevalence high high low moderate moderate or low low probably low low probably low unknown low moderate high

6. Incidence and prevalence Regional data Middle East Country Population Total MS patients Total RRMS patients Saudi Arabia 22’024’000 1’760 1’060 Kuwait 1’974’000 185 110 Palestine 2’896’000 670 400 Tunisia 9’593’000 605 360 Libya 5’116’000 300 180 Jordan 4’999’000 550 330 Iraq 22’676’000 910 545 Lebanon 3’578’000 750 450

7. Incidence and prevalence Population Total MS patients Country Middle East 72‘853‘790 5‘730 West Europe 350‘367‘700 386‘000 Eastern Europe 76‘750 78‘475‘500 Canada 50‘000 31‘281‘100 USA 300‘000 275‘562‘700 South Africa 1‘500 43‘420‘000 South America 25‘000 209‘815‘550 Australia 12‘000 19‘169‘100

8. Pathology • MS is a chronic inflammatory demyelinating disease of the central nervous system (CNS). • MS is characterized by acute and chronic lesions of the white matter in the CNS. • Among other aftereffects, the inflamed white matter leads to a demyelination of the axons. • Axonal loss means that neuronal transmission of electrical signals is no longer possible and cannot be restored. • Axonal loss might occur at an early stage of the disease, even before visible symptoms appear.

9. PATHOLOGY AND PATHOGENESIS • MS lesions characterized by • Demyelination of white matter with relative preservation of axons, gliosis and varying degrees of inflammation • Sites predilections • Optic nerve , perivantricular, spinal cord, brain stem, and cerebellum

10. PATHOLOGY AND PATHOGENESIS • Acute lesionlymphocutes and plasmscells • Chronic lesionsastrocytic gliosis and remyelination

11. Demyelination and axonal degeneration in MS Waxman S, NEJM 338, 5, 323, 1998

12. MS & AETIOLOGY • Remains unresolved • Suggestive • Environmental agent • genetically susceptible individual • Incidence of the disease • Results of migration

13. MS & AETIOLOGY 3- Viral 4- Genetic • Japaness low incidence • Twin studies • Higher in monozygotic than dizygotic 30% vs 4% • Association of MS with HLA

14. IMMUNOLOGICAL MECHANISM • Presence of immunocompetent cells: T and B lymphocytes and macrophage in areas of recent demyelination • Macrophages, endothelial and astrocytes cells • The detection of interleukin-2 receptors on lymphocytes

15. IMMUNOLOGICAL MECHANISM • Elevated level of IgG in the CSF of MS patients • The oligoclonal bands pattern on immunoelectrophoresis in CSF and not in the serum • Myelin basic protein-reactive T lymphocytes have been identified in the CSF and serum of patients with MS

16. CLINICAL MANIFESTATIONS and COURSE • Unpredictable course • rapidly progressive • Benign • mild exacerbation • complete remissions • minimal disability • Exacerbation-remitting • Chronic - relapsing • Chronic progressive

17. CLINICAL MANIFESTATIONS • Common mode of presentation • Optic neuritis • Sensory disturbances • Leg weakness • Sphincters disturbances • Brain stem and cerebellum dysfunction • Relapsing -Remitting 90% • Many patients with R-R course pass into progressive course • Progressive course 10%

18. CLINICAL MANIFESTATIONS • OPTIC NEURITIS • Eye pain often on eye mouvements • Progressive visual loss • Visual deficit usually improves after 2-3 weeks • Persistent severe visual loss is uncommon

19. CLINICAL MANIFESTATIONS • Fondus examination • Often is normal • Swollen disc • white disc, haziness of the cup • Pupillary reflexes often showed afferent pupillary defect

20. BRAIN STEMSYMPTOMS AND SIGNS • Diplopia, facial pain, vertigo, diziness,and hearing disorders • Signs suggestive cranial neuritis • Diplopia • Internuclear ophthalmoplagia (INO) • Reduced adduction of the eye on the side of the lesion with nystagmus in the abducting eye • Uni/bilateral

21. SYMPTOMS AND SIGNS SUGGESTIVE LONG TRACTS SYSTEMS • Weakness, Pyramidal signs • Sensory symptoms Patchy sensory distribution, LHERMITT’S sign Pain Usually chronic, dysaestheasia, painful leg spasm. • Sphincters disorders: Frequency, urgency, incontinent, and hesitancy and difficulty initiating micturation Constipation, faecal incontinence

22. SYMPTOMS AND SIGNS • Cognitive and psychiatric abnormalities: Failure of memory, lack of concentration and executive functions Depression, anxiety, and euphoria

23. DIAGNOSIS of MS • No specific test for MS • Multiple signs and symptoms • Remissions and exacerbation's • Criteria for clinical diagnosis of MS

24. Criteria for clinical diagnosis of MS NO of AttacksEvidence of more than one lesion CSF,OCB • Clinically Definite ClinicalLaboratoryor IgG • A1 2 2 • A2 2 1 and 1 • Laboratory-Supported Definite • B1 2 1 or 1 + • B2 1 2 + • B3 1 1 and 1 + • Clinical Probable • C1 2 1 • C2 1 2 • C3 1 1 and 1 • Laboratory-Supported probable • D1 2 0 0 +

25. McDonald committee for Diagnosis of MSDIS=disseminated in space, DIT=disseminated in time • 1. Definite MS on clinical grounds:  • DIS: 2 or more lesions • DIT: 2 or more attacks • 2. Localized disease • DIS: 1 lesion, need • MRI to prove DIS, or • MRI finding and positive CSF finding; or  • urther clinical attack at a different location • 3. Multifocal single attack, need • 2nd attack to confirm diagnosis • 4. Single attack, single lesion • DIS: Need MRI prove of • DIS, plus DIT: Need MRI or clinical proof of second attack • 5. Primary progressive disease • DIS: Need MRI, Evoked potential and CSF • DIT:  • MRI proof of DIT, • or progression for over one year

26. Differential Diagnosis • Encephalomyelopathy • SLE, CNS vasculitis • Vascular malformation • Gliomas of the brainstem • Syringomyelia • Progressive multifocal leuckoencephalopathy • Infection : Brucella, TB, AIDS

27. Laboratory Data • There is no pathognomonic test for MS. • Neuroradiolog • CSF investigations • Evoked Responses

28. MRI & MS • Multiple white matter lesions • Gadolinium contrast differentiates between new and old lesion • Similar lesions can be seen encephalitis, vasculitis • Asymptomatic patients

29. MRI: FLAIR & T1 with Gadolinium(Noseworthy J, et al NEJM, 2000)

30. MRI: T1 “Black Holes”

32. CSF & MS • WBC is often increased • Lymphocytic plucytosis • Activity of the disease • >100 cells/mm3 • Total protein is increased 40% • < 100mg/dl • Increased IgG 60-70 % • Increased IgG Index 80-90

33. CSF & MS • Oligoclonal bands • Often positive 80-90 % • Can be seen in other CNS disorders : infection, SSPE • Myelin basic protein

35. Evoked Responses&MS • Demonstrate the existence of clinically unsuspected lesions • Simple, noninvasive and harmless tests • Visual Evoked Responses • Auditory Evoked Responses • Somatosensory Evoked Responses

36. Visual Evoked Potentials(Baker’s Clin Neurol 2003)

37. TREATMENT & MS • No curative treatment yet • For the acute attack: • ACTH IM injection for 10-14 days • Methylprednisolone 1 gm daily for 5 days • Prophylactic therapy • Reduce the frequency of exacerbations/slow the rate of progression of disability • Immunosupressive therapy • Beta-Interferon-1B, 1A • Symptomatic treatment

38. ACUTE DISSEMINATED ENCEPHALOPATHY • Monophasic encephalitis or myelitis • White matter of the brain or spinal cord • Process may be severe, fatal, or mild • Multiple foci of perivenular lymphocyte and mononuclear cell infiltration with demyelination • Follow vaccinations, acute infectious illnesses and may occur without any obvious antecedent

39. CLINICAL MANIFESTATIONS • Headache, delirium and coma , Seizures • Meningeal irritation and fever • Focal signs • Spinal cord involvement • Cerebellum and cranial nerve palsies are rare • CSF: Increase protein, Increase cells lymphocytes Rarely it is normal • MRI is often abnormal