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الكلية كلية الطب
القسم الباطنية
المرحلة 5
أستاذ المادة وهاب رزاق عبد الامير الخفاجي
4/21/2011 9:21:37 AM
<>MULIPLE SCLEROSIS
Definition- is a demyelinating disease characterized by selective destruction of
CNS myelin.
It is second only to trauma as a cause of neurologic disability in early to middle
adulthood.
Epidemiology and Etiology-
It typically affects people between 20-40 years with female to male ratio 2:1.
Incidence varies with latitude and being low in equatorial areas and higher in
temperate zones of both hemispheres.
Studies suggest that multiple sclerosis is caused by interplay of multiple genetic
and environmental factors (viral, socioeconomic status).
Risk for first degree relative of the patient is 2-3%.
Pathology-
Multiple sclerosis is characterized by a triad of inflammation,
demyelination and gliosis (scarring). Inflammation starts with the entry of
activated T-lymphocytes through the blood brain barrier to recognize
myelin-derived antigens on the surface of CNS antigen-presenting cells,
the microglia; and undergo proliferation. The resulting cascade initiates
destruction of the oligodendrocyte- myelin.
The lesion of multiple sclerosis is called “plaque” which occurs most
commonly in the periventricular regions of the brain, optic nerves, the
subpial regions of the spinal cord and cerebellum.
Clinical features:
Demyelinating lesions cause symptoms and signs that usually come on
subacutely over days or weeks and resolve over weeks or months.
Common presentations are:
a- optic neuritis: gradual loss of vision in one eye with painful eye
movements and usually disc swelling on fundoscopy. When the disc
remains normal by fundoscopy, it is called” retro bulbar neuritis” (the patient
sees nothing and the doctor sees nothing).
Optic neuritis leads to afferent papillary defect (APD) - loss of direct and
consensual response to light stimulation of the affected eye- even after
resolution of symptoms.
b-relapsing- remitting sensory symtoms: burning pain or parasthesia
involving the extremities, face or trunk usually asymmetrical.
c- Subacute painless spinal cord lesion- including asymmetrical
paraparesis and Brown- Sequard Syndrome (ipsilateral motor weakness
and loss of proprioception and vibration with contra lateral loss
pain and temperature).
d-acute posterior fossa syndrome – mostly internuclear ophthalmoplegia
(failure of adduction of the ipsilateral eye with nystagmus of the
contralateral abducting eye), cerebellar ataxia.
e- paroxysmal signs: like Lermitte’s sign( tingling in spine or limbs on neck
flexion), Uthoff sign (exaggeration of symptoms by heat), trigeminal
neuralgia.
· Significant intellectual impairment is unusual.
· Three main clinical types of multiple sclerosis have been described:
1- Relapsing-remitting: accounts for 80%, and characterized by attacks that
generally evolve over days to weeks followed by variable recovery.
2- Secondary progressive: the patient experiences a steady deterioration in
function unassociated with acute attacks. Approximately 50% of relapsing
remitting disease will have developed secondary progressive disease after
15 years.
3-Primary progressive: 20% of patients follow a slowly progressive course
from the start.
Investigations: there is no specific test for multiple sclerosis.
a- MRI is the most sensitive technique for imaging lesions in the brain and
spinal cord (especially with contrast) and in excluding other causes of
deficit.
b- Evoked Potential (EP) - visual EP can detect silent lesions in up to 70%
of patients, but auditory EP and somatosensory EP are seldom of
diagnostic value.
c- CSF study: may show lymphocytes predominance in the acute phase
and oligoclonal bands between attacks.CSF protein may be normal or
mildly elevated.
Diagnosis:
The diagnosis of multiple sclerosis requires the demonstration of lesions
being disseminated in time and place. It depends on the MACDONALD
CRITERIA.
· Differential diagnosis:
1- Acute disseminated encephalomyelitis (ADEM).
2- CNS infections –neurobrucellosis, tuberculosis, neurosyphilis.
3- Behcet’s disease.
4- Connective tissue disease.
5- Antiphospholipid antibody
6- CNS vasculitis.
7- Vitamin B12 deficiency.
8- Neurosarcoidosis.
Treatment:
· Acute relapse: pulses of methylprednisolone either i.v. 1gm/day for
3-5 days or orally 500mg/day for 5 days shorten the duration of the relapse.
· Preventing relapses:
A- Interferon ?1a and 1b reduces the number of relapses by 30%.
B- Glatiramer acetate.
C- natalizumab: monoclonal antibody.
D- metoxantrone: cytotoxic drug.
E- Others: azathioprine, cyclophosphamide.
F- I.V. immunoglobulin.
· Symptomatic treatment
a- Spasticity – physiotherapy, baclofen (liorisal), tizanidine, botulinum toxin
Injection for focal spasticity.
b- Ataxia- INH, clonazepam.
c- Dysasthesias - carbamazepine, gabapentin, phenytoin,amitryptiline.
d- Bladder symptoms – intermittent self catheterization in paralytic bladder
and anticholinergics (imipramine or oxybutinin) in spastic bladder.
e- Fatigue – amantadine, modafinil or amitriptyline.
f- Impotence – sildenafil.
Prognosis : good prognosis is associated with
i- female gender
ii- complete recovery from the attack
iii- age less than 40 years.
iv- optic neuritis and sensory symptoms (rather than motor and cerebellar
symptoms).
v- relapsing-remitting disease.
Approximately 5% of patients die within 5 years of onset.
Other demyelinating diseases
ACUTE DISSEMINATED ENCEPHALOMYELITIS
· This is an acute, usually monophasic, demyelinating condition.
· It often occurs a week or so after a viral infection, especially measles and
chickenpox, or following vaccination, suggesting that it is immunologically
mediated.
· Clinical features include headache, vomiting, pyrexia, confusion and
meningism, with focal or multifocal brain and spinal cord signs. Seizures or
coma may occur.
· MRI shows multiple high-signal areas in a pattern similar to that of multiple
sclerosis, although often with larger areas of abnormality.
· The disease may be fatal in the acute stages.
· Treatment with high-dose intravenous methylprednisolone.
ACUTE TRANSVERSE MYELITIS
· It is an acute, often monophasic, inflammatory demyelinating disorder
affecting the spinal cord over a variable number of segments.
· Patients may be of any age and present with a subacute paraparesis with a
sensory level, often with severe pain in the neck or back at the onset.
· MRI is needed to distinguish this from a compressive lesion of the spinal
cord.
· Treatment is with high-dose intravenous methylprednisolone.
NEUROMYELITIS OPTICA
المادة المعروضة اعلاه هي مدخل الى المحاضرة المرفوعة بواسطة استاذ(ة) المادة . وقد تبدو لك غير متكاملة . حيث يضع استاذ المادة في بعض الاحيان فقط الجزء الاول من المحاضرة من اجل الاطلاع على ما ستقوم بتحميله لاحقا . في نظام التعليم الالكتروني نوفر هذه الخدمة لكي نبقيك على اطلاع حول محتوى الملف الذي ستقوم بتحميله .
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