Peripheral+Neuropathy

//Western Diagnosis// syndrome of sensory loss, muscle weakness and atrophy, dec DTR’s, vasomotor sx

Classification
1. mononeuropathy - single nerve 2. multiple mono - 2 or more nerves in separate areas 3. polyneuropathy - many nerves simultaneously

Etiology
a. trauma b. pressure: superficial nerves at bony prominences
 * Mono**

a. collagen-vascular diseases b. metabolic (DM) c. infectious (Lyme, HIV)
 * Multiple**

a. autoimmune b. toxic c. nutritional def (B vits) d. metabolic (hypothyroidism, DM) e. malignancy
 * poly**

Signs & Symptoms
a. pain, weakness, paresthesia b. + Tinel’s sign c. compression and entrapment syndromes i. ulnar nerve palsy - claw hand deformity ii. carpal tunnel syndrome - compression of median nerve - sensory def and paresthesias in radio-palmar hand - differentiate from C6 nerve root compression - vit. B6 100mg TID iii. radial nerve palsy - wrist drop iv. peroneal nerve palsy - foot drop
 * mono, single and multiple**

a. symmetric b. sensory, motor, vasomotor sx c. insidious d. sensory abN in lower extremities e. tingling, numbness, burning f. < night g. position and vibration senses dec h. objective sensory loss in stocking-glove distribution i. dec or absent DTR’s j. distal muscle weakness and atrophy k. nocturnal D l. bl and bowel incontinence m. impotence n. ortho hypo o. smooth, shiny skin p. pitted, ridged nails q. dry, pale skin or dusky, sweaty skin
 * Poly**

Diagnosis
1. find cause 2. CBC - pernicious anemia, lead poisoning 3. chem screen - liver, kidney failure, DM 4. thyroid function tests 5. EMG, nerve conduction velocities 6. muscle biopsy

Treatment
1. tx underlying problem

Special cases

Thoracic outlet syndrome
a. compression of brachial plexus or subclavian vessels b. sx as in peri neuro c. + Adson’s test - extension and contralateral rotation of neck, abduction and lateral rotation of arm, deep inspiration, palate radial pulse and ask if sx returning

Guillain-Barre Syndrome
a. acute rapidly progressive inflammatory polyneuropathy b. muscle weakness and distal sensory loss c. onset 5 days to 3 weeks after mild infectious disorder, surgery, immunization d. probably autoimmune e. most common acquired demyelinating neuropathy

i. symmetric weakness with paresthesias beginning in legs and moving to arms ii. absent DTR’s iii. facial and oropharyngeal muscle weakness iv. 5-10% resp failure v. BP fluctuations, arrhthymias vi. 5% die v. 90% reach maximal weakness in 2-3 wk
 * Signs & Symptoms**

i. clinical
 * Diagnosis**

i. severe is medical emergency ii. maintain airway iii. plasmapharesis: removal of plasma proteins
 * Treatment**

i. considerable improvement over a period of months is usual ii. 30% have residual weakness at 3 yrs iii. 10% relapse after initial improvement and develop chronic relapsing polyneuropathy
 * Prognosis**

Bell’s palsy
a. unilateral facial paralysis b. sudden onset c. swelling of facial nerve possibly autoimmune or viral d. extent of recovery varies on extent of nerve damage

Trigeminal neuralgia
a. sharp, lancinating pain usually over mandibular or maxillary divisions of trigeminal nerve b. last from secs to mins c. no signs only hx: if + sns, look for another cause d. possibly compression of trigeminal nerve

Amyotrophic lateral sclerosis (ALS)
a. progressive degeneration of ant horn cells, corticospinal tracts, bulbar motor nuclei b. combined motor neuron disease - UMN & LMN c. muscular weakness and atrophy initially in hands d. progression asymmetric e. initially dec DTR’s f. then muscle fasciculations, spasticity g. inc DTR’s, extensor plantar reflexes h. dysarthria, dysphagia i. dx by onset during middle to late life, progressive & generalized motor involvement with no sensory abN j. 50% die within 3 yrs of onset