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Multiple Sclerosis Optic Neuritis Myasthenia Gravis, GBS, Lambert Eaton MS disease that affects the central nervous system. It occurs when the body's immune system attacks the protective covering of nerve fibers, causing inflammation and damage. • on the location and severity of the damage to the nervous system. Common symptoms to look out for in exam: • optic neuritis, diplopia, hemianopia • worsening of vision following rise in body temp • numbness, pins and needles, trigeminal neuralgia • muscle weakness • intentional tremor, ataxia , speech, falls • urinary incontinence, retention • more common in women MS • Relapsing-remitting disease: • most common form, accounts for around 85% of patients • acute attacks (e.g. last 1-2 months) followed by periods of remission, usually >30 days • Diagnosis requires demonstration of lesions disseminated in time and space • MRI: sensative but not specific. _> 2 lesions disseminated in time and space. • CSF oligoclonal bands (and not in serum) +increased intrathecal synthesis of IgG MS • Acute relapse High-dose steroids (e.g. oral or IV methylprednisolone) may be given for 5 days to shorten the length of an acute relapse. • Disease modifying drugs • reduce risk of relapse • natalizumab/ocrelizumab/beta- interferon (monoclonal antibody)MS • Fatigue once other problems (e.g. anaemia, thyroid or depression) have been excluded • NICE recommend a trial of amantadine • mindfulness training and CBT • Spasticity • baclofen and gabapentin are first-line. • Other options include diazepam, dantrolene and tizanidine • physiotherapy • Bladder dysfunction • ultrasound first to assess bladder emptying - anticholinergics may worsen symptoms in some patients • if significant residual volume → intermittent self- catheterisation • if no significant residual volume → anticholinergics may improve urinary frequency eg. Tolterodine/ OxybutyninOPTIC NEURITIS • Optic Neuritis is a condition where the optic nerve, which connects the eye to the brain, becomes inflamed and damaged. This can cause vision loss or blurred vision, as well as pain and discomfort around the eye. • Optic Neuritis is often associated with multiple sclerosis, DM, syphilis. but it can also occur as a standalone condition. • unilateral decrease in visual acuity over hours or days • poor discrimination of colours, 'red desaturation' • pain worse on eye movement • relative afferent pupillary defect • central scotoma • MRI brain and orbit diagnostic • Treatment: HIGH DOSE STEROIDSMY ASTHENIA GRAVIS • Mcauses muscle weakness and fatigue. It occurs when the body's immune system attacks the acetylcholine receptors. • more common in women • mweaker during periods of activity and slowly improve after periods of rest!! • proximal muscle weakness: face, neck, limb girdle • ptosis • extraocular muscle weakness: diplopia • dysphagia • myasthenic snarl/smiling • ‘peek sing’ of obicularis fatiguability- eyelids begin to seperate after manual opposition to closure • voice fades (dysphonia) after counting to 50 MY ASTHENIA GRAVIS • Associations • thymomas in 15% • pregnancy • low potassium • infection • change of climate, emotion, exercise • Gentamycin, opiates, tetracycline, quinine, beta blockers. • autoimmune disorders: pernicious anaemia, autoimmune thyroid disorders, rheumatoid, SLE • thymic hyperplasia in 50-70% MY ASTHENIA GRAVIS Investigations • CT thorax to exclude thymoma • CK normal • antibodies to acetylcholine receptors • positive in around 85-90% of patients • 40% are positive for anti-muscle-specific tyrosine kinase antibodies (MUSK) • Management • long-acting acetylcholinesterase inhibitors • pyridostigmine is first-line • Thymectomy • Relapses: • p1mg/kg. decrease dose on remission. can take months + osteoporosis propylaxis. • aalso be used cyclosporine, mycophenolate mofetil mayMY ASTHENIC CRISIS • life threatening weakness of respiratory muscles during relapse • monitor Forced Vital Capacity • ventilator support? • Tx: plasmapharesis (removes AchR antibodies from circulation) or IVIg • identify trigger (infection, medications)LAMBERT EA TON • Lambert-Eaton syndrome is caused by an antibody directed against presynaptic voltage-gated calcium channel in the peripheral nervous system. • repeated muscle contractions lead to increased muscle strength (in contrast to myasthenia gravis) • limb-girdle weakness (affects lower limbs first) • hyporeflexia and weakness, improve after exercise • autonomic symptoms: dry mouth, impotence, difficulty micturating • ophthalmoplegia, ptosis and respiratory involvement not commonly a feature (unlike in myasthenia gravis) • paraneoplastic (small cell lung cancer) • EMG • incremental response to repetitive electrical stimulationLAMBERT EA TON • EMG • incremental response to repetitive electrical stimulation • Management • treatment of underlying cancer • prednisolone and/or azathioprine (immunosuppression) • 3,4-diaminopyridine is currently being trialled • works by blocking potassium channel efflux in duration is increased. Calcium channels can then be open for a longer time and allow greater acetylcholine release to the stimulate muscle at the end plate • intravenous immunoglobulin therapy and plasma exchange may be beneficialGBS + Miller Fisher • Guillain-Barre syndrome describes an immune-mediated demyelination of the peripheral nervous system often triggered by an infection (classically Campylobacter jejuni) • anti-GM1 antibodies Miller Fisher syndrome • variant of Guillain-Barre syndrome • palsy, areflexia and ataxia. The eye muscles are typically affected first • usually presents as a descending paralysis rather than ascending as seen in other forms of Guillain-Barre syndrome • anti-GQ1b antibodies are present in 90% of casesGBS • back/leg pain in the initial stages of the illness • reflexes are reduced or absent • sensory symptoms tend to be mild (e.g. distal paraesthesia) with very few sensory signs = mainly motor • there may be a history of gastroenteritis • respiratory muscle weakness • cranial nerve involvement • diplopia • bilateral facial nerve palsy • oropharyngeal weakness is common • autonomic involvement • urinary retention • diarrhoea • Ix: LP —→ isolated rise in protein, albuminocytologic dissociation • nerve condution studies may be performed • decreased motor nerve conduction velocity (due to demyelination) GBS • IV immunoglobulins • Plasma exchange (alternative to IV IG) • Supportive care • VTE prophylaxis (pulmonary embolism is a leading cause of death) • In severe cases with respiratory failure patients may need intubation, ventilation and admission to the intensive care unit.MS Myasthenia Gravis LE GBS Demyelinating Autoimmune: AI: Voltage-gated calcium Demyelination of PNS: Acetlycholine receptors channels Campylobacter jejuni), anti-GM1 antibodies Optic neuritis Muscle fatiguability after Repeated contractions= more Hx of Gastroenteritis activity , ptosis, strength Respiratory muscle Less common- eye symptoms weakness Sensor, ataxia, Urine incontinence Proximal muscle weakness Lower limbs affected first Few sensory signs Autonomic dysfunction absent/reduced reflexes, Oligoclonal bands , MRI CT thorax thymoma, EMG: repetitive stimulation= LP —→ isolated rise in antibody AchR, FVC more activity protein, albuminocytologic dissociation Nerve conducton studies Acute relapse- High dose steroids Acute : steroids / Ventilation? azathioprine, cyclosporine