1. Central and Peripheral Neuropathies Nicholas Cascone, PA-C

2. Multiple sclerosis – general characteristics  Inflammation of white matter with multiple foci of demyelination  Pattern of episodes may be relapsing- remitting or chronically progressive  Onset between 18 and 45, 2:1 women:men

3. Multiple sclerosis – clinical features  Most common presentations:  Weakness, numbness, tingling, unsteadiness in a limb  Spastic paralysis of lower limbs  Retrobulbar neuritis causing vision loss  Disequilibrium  Sphincter disturbance: urinary urgency, hesitancy  Symptoms disappear after days or weeks, sometimes leaving residual deficit  Cognitive deficit or psychiatric disorders may occur

4. Multiple sclerosis – labs and imaging  MRI is best, CT less helpful  Lymphocytosis, increased protein, oligoclonal bands of IgG in CSF immediately after acute relapse  Visual, auditory, sensory electrocerebral responses  Diagnosis cannot be made on laboratory findings alone  Diagnosis requires evidence that two or more regions of central white matter affected at different times

5. Multiple sclerosis – treatment  Corticosteroids for acute relapse  β-interferon, glatiramer acetate, methotrexate are used to slow progression of disease  Symptomatic treatment of spasticity, fatigue, urinary retention  Half of all patients are without significant disability 10 years after diagnosis

6. Amyotrophic Lateral Sclerosis  aka Lou Gehrig’s disease  Degenerative upper and lower motor neuron disease affecting limbs  Upper motor neuron disease: spasticity, brisk reflexes, Babinski sign  Lower motor neuron disease: weakness, muscle atrophy, fasciculations, paralysis  Diagnosis by EMG findings in all three spinal regions or two spinal regions and bulbar musculature (face, head, neck, eyes)  Treatment: riluzole slows progression; bracing, physical therapy, antispasmodics, anticholinergics

7. Encephalopathies  Wernicke’s encephalopathy: confusion, ataxia, nystagmus/ophthalmoplegia, peripheral neuropathy d/t thiamine deficiency  Most common in EtOHism, AIDS  Tx with thiamine  Hepatic encephalopathy:  Presentation ranges from day-night reversal to intellectual impairment to coma; asterixis is present  Caused by buildup of serum toxins (chiefly NH 3 ) due to hepatic failure  Most common in EtOHism, especially post-TIPS and with GI bleeding  Tx with low protein diet, lactulose, neomycin, zinc  Other causes: HTN, Lyme disease, rubella, Reye’s syndrome, Li +, metabolic, vCJD (caused by eating meat infected with mad cow diease)

8. Bell’s palsy – characteristics and clinical features  Unilateral facial muscle weakness without apparent cause  more frequent in pregnant women, DM  associated with trauma, infection, neoplasm, toxin exposure  Clinical features  Abrupt onset  Paralysis involves hairline to chin; pts cannot close the affected eye, wrinkle brow, smile  Other possible features: ipsilateral earaches, hyperacusis, changes in taste/lacrymation

9. Bell’s palsy - treatment  Treatment with steroids/acyclovir if:  Patients with poorer prognosis: hyperacusis, complete palsy, advanced age, severe pain  Within 5 days of onset of symptoms  60% recover completely with no treatment  Symptomatic treatment: lubricating eyedrops

10. Trigeminal neuralgia  Momentary episodes of lancinating facial pain near one side of mouth radiating to ear, eye or nostril  Triggered by touch, movement, drafts, eating  Treatment: carbamazepine, phenytoin, baclofen, gabapentin; decompression of nerve root/rhizotomy if medical failure

11. Diabetic peripheral neuropathy  70% present as mixed (motor, sensory, autonomic) neuropathy; remainder are sensory  Pts present with numbness, pain, burning, paresthesia in LE > UE; reduced DTRs, impaired vibratory/position sense  Autonomic dysfunctions include orthostasis, arrhythmia, impaired thermoregulation, bowel/bladder/gastric/sexual dysfunction  Diagnosis by NCS, additional workup to exclude uremia, EtOHism, nutritional deficit, hypothyroid, vasculitis, amyloidosis  Treatment by tight glycemic control; pain meds include gabapentin, carbamazepine, amitriptyline, phenytoin

12. Guillain-Barré syndrome – clinical features  Acute progressive idiopathic polyradiculoneuropathy causing ascending symmetric weakness  Usually begins in the legs  Motor symptoms far outweigh sensory, but paresthesia, dysesthesia and pain are common  Autonomic disturbances (tachycardia, arrhythmia, BP changes, swallowing difficulty, pulmonary and temp regulation dysfunction) are common and may be severe or life-threatening  Associated with infection by C. jejuni

13. Guillain-Barré syndrome – labs and treatment  Labs:  EMG/NCV show marked slowing, deneveration and axonal loss  CSF with high protein but normal cell count  Treatment:  Hospitalization with respiratory monitoring  IV immunoglobulin  Plasmapheresis  Only 10-20% have persistent disability

14. Myasthenia gravis – clinical features  Autoimmune destruction of acetylcholine receptor at motor end plate  Typically presents with ptosis, diplopia, difficulty chewing/swallowing/breathing, progressive proximal limb weakness which improves with rest  Normal sensation and reflexes  Administration of edrophonium (short-acting anticholinesterase) causes marked but transient clinical improvement

15. Myasthenia gravis – labs and treatment  Labs:  CXR to rule out thymoma  EMG shows decrementing muscle response to repeated stimulation  Serum assay for acetylcholine receptor antibody  Treatment  Symptomatic treatment: neostigmine, pyridostigmine  Thymectomy under age 60  Steroids for those post-thymectomy and unresponsive to anticholinergics  Plasmapheresis or IV immunoglobulin if all else fails