Neuromuscular Disorders

-Smriti UpretyRoll no.: 51

BDS- 4th year

CONTENTS:• Introduction• Neuromuscular disorders

Multiple SclerosisAlzheimer’s diseaseMyasthenia GravisParkinsonismCerebrovascular diseasesSeizure disorders

• Conclusion• Reference

Introduction:

Multiple Sclerosis- Is an important cause of long- term disability in

adults- Both genetic & environmental factors- An attack of CNS inflammation activated T lymphocytes across the blood-brain barrier Recognize myelin-deriver antigens Resulting inflammatory cascade releases cytokines Destruction of the oligodendrocyte-myelin unit by macrophages- Reduces the impulse propagation or causes complete

conduction block

• Clinical Features: - peak age• Optic neuritis(diminished visual acuity, dimness,

decreased color perception• Limb weakness• Spasticity with painful muscle spasms• Ataxia• Bowel & bladder dysfunction

Increased Temperature

Others: CSF - cell count - oligoclonal bands of IgGMRI

Management:- Treatment of the acute episode - Methylprednisolone

- Prevention of future relapses - Azathioprine, Natalizumab

- Management of complications & disability - Physiotherapy - Baclofen - Isoniazid - Carbamazepine

Alzheimer’s disease

- dementia acquired deterioration in cognitive abilities that impairs the successful performance of activities of daily living

- Memory is the most common

- Alzheimer’s disease: most common form- Characterized by neuritic plaques and neurofibrillary tangles

coupled with a degeneration of neurons and synapses

- Neuritic plaques central core of amyloid β (Aβ) peptide

- Imbalance between the production & clearance of Aβ in the brain disease initiating event neural degeneration & dementia

- Neurofibrillary tangles: abnormally phosphorylated tau proteins

• Clinical features

- slowly progressive disorder represented by a continuum of clinical characteristics

- 3 recognized stages: 1) preclinical AD 2) mild cognitive impairment due to AD 3) dementia due to AD

• Forgetfulness• Memory loss affect daily activities

(following instructions, driving, decision making)

Initiallly

• loss of cognitive ability, agitation• delusions, psychotic behavior

Advanced AD

• rigid, mute, incontinent, bedridden

End-stage

• Diagnosis- preclinical biomarker assessment (Aβ protein in brain) markers of downstream neurodegeneration decreased metabolism in temporal and parietal cortex brain atrophy on MRI

- Medical history, clinical and neurologic findings

- Definite AD: Autopsy- Diagnostic analysis of CSF, EEG, MRI, CT

Treatment• therapy is aimed at slowing the progression of the

disease• Cholinesterase inhibitors, Antidepressants,

Antipsychotics- mild to moderate AD• Memantine- moderate to severe AD

Parkinsonism

- Chronic, progressive, neurodegenerative disorder - rigidity, resting tremors, - bradykinesia, gait disturbance- A more contemporary view: cognitive deficits, neuropsychiatric changes, dysautonomia

- The American Academy of Neurology has developed diagnostic, assessment, and treatment guidelines

- Idiopathic and “Parkinsonian Syndromes”

- 446 cases per 100,000 population

- Degeneration of the dopaminergic cells in Pars compacta of the Substantia nigra

- Four cardinal signs: resting tremor (in hands, arms, legs, jaw and face) rigidity or stiffness (limbs and trunk) bradykinesia postural instability or impaired balance and

coordination

• dementia, depressions, anxiety, apathy, irritability,• Orthostatic hypotension, constipation, urinary

frequency & urgency, abnormal sweating

• Diagnosis - clinical genetic markers - health history neurologic examination response to levodopa therapy

- anatomic and functional brain imaging, CSF evaluation, laboratory testing

Treatment:- Variety of medications and procedures (only dramatic relief from the symptoms)

- Dopamine replacement therapy using Levodopa Carbidopa Bromocriptine

Myasthenia Gravis- Chronic neuromuscular disease caused by

autoimmune destruction of the skeletal neuromuscular junction resulting in impaired neurotransmission and muscle weakness

Autoantibody:• Anti- AChR• MUSK

• Prevalence: 15-20 per 100,000

• Clinical features - Ocular symptoms diplopia &/or ptosis - facial & masticatory muscle weakness results in dysphagia, asymmetry, dysarthria

- severe advanced- respiratory difficulty

Diagnosis- Clinical examination- Biopsy Confirmed by a variety of bedside, electrophysiological & immunological tests: serum anti-AChR

• Treatment- Reduction of pathologic antibody production or presence, and/or

replacement/preservation of the pathologic antibody target (AChR)

- Anticholinergic drugs- Thymus tumor thymectomy- Corticosteroids & nonsteroid immune

suppressants

Seizure Disorders- A paroxysmal event due to abnormal, excessive,

hyper synchronous discharge from neuronal aggregates in the CNS

- Epilepsy: group of neurological disorders characterized by recurrent seizure activity-

- Predisposing factors: Hypoxia, Hypoglycemia, Hypocalcaemia, Stress, Fatigue, Alcohol ingestion

• Investigations- After a first seizure, immediate cerebral imaging with CT- MRI- EEG- Investigations for infective, toxic, metabolic

causes

• Treatment- Lifestyle modification- Anticonvulsant therapy

Cerebrovascular Disease- Disorders that result in damage to the cerebral

blood vessels impaired cerebral circulation- Stroke or Cerebrovascular accidents includes Transient Ischemic attack & Reversible Ischemic neurologic deficit

- 4th leading cause of death- Age

impaired cerebral blood flow ischemia and energy failure

- Clinical feature vary depending on the time and the location of the affected brain region

- Commonly- sensory and motor deficits, paresis in extraoral muscles, altered mental status, dizziness, nausea, seizures, impaired speech, memory, reasoning and concentration

Diagnosis- Clinical examinations- Noncontrast CT, MRI- Laboratory evaluation complete blood count urinalysis coagulation profile blood culture echocardiography lumbar puncture

• Treatment:- Outcome is significantly affected by the timeliness of

treatment

- Reduction of hypertension (diet, exercise, smoking cessation, stress reduction, medical therapy, anticoagulant or antiplatelet medications)

- Administration of t-PA from 3 to 4.5 hours after stroke

Conclusion

- Diseases affecting the neuromuscular systems have prevalence rate of 3-5%

- Thus, every health care provider will encounter a patient

- Adequate knowledge about each of these disorders must be known for the management of the conditions.

REFERENCE• Burket’s Oral Medicine - Michael Glick

• Davidson’s Principles & Practice of Medicine - Nicki R. Colledge, Brian R. Walker, Stuart H. Ralston

• Essentials of Medical Physiology - A B S Mahapartra

Thank-you