Flashcards in PNS Deck (51):
NMJ disorder. antibodies block and distort achR. 2 peaks: 20-30- w>M, 60-80s- M>W. Sx: flucturating sc of M weakness- ocular, bulbar, neck. ptosis, fatigable chewing, weak neck extensor- dropped head syndrome. better in morning. double vision bc many achR in M of eye. dysphagia, bilateral ptosis
dx: EMG-decremental response to repetitive stimulation, then give trial of edrophonium, send ab against AchR- pos in 85% .
after confirm dx, screen for tumor of thymus
other dx: MuSK ab- in generalized MG searing for anti-AChR ab- tend to only have ocular findings.
single fiber EMG- jitter
readily reversible acetylcholinesterase inhibitor. Tensilon test. not specific for MG. eyelid M respond first.
ice pack test
for MG pt, put icepack on forehead of min- temporary reversal of ptosis.
respiratory insufficiency out of proportion to M weakness. or incr generalized weakness to bulbar M needing intubation. emergency! panting like a dog, have freq PFT and NIF to ck for decline. if mild- IVIG or plasmapheresis immediate to dear ab load in blood- provide relief (wks). if severe -intubate. though some prefer proactive intubation. if has thymoma- do thymectomy
lambert eaton myasthenic syndrome
paraneoplastic D. ab against presynaptic ca-ch. can be in small cell carcinoma of lung. slowly progressive. spares eyes unlike MG. brief improvement in strength with exercise.
EMG- incremental response to repetitive stimulation.
mestinon. maintanence tx for MG>
steroid immunosuppressant for MG.
guillain barre syndrome
AI. often following GI illness. progressive ascending weakness with min sensory sx. sx dec over hr to days. sig back pain due to info nerve roots. loss of reflexes! LP: normal WBC, RBC, protein high= albuminocytologic dissociation, takes a wk to dev so CSF may be normal acutely. often proceed by campylobacter jejune infection.
autonomic dysfunction (BP changes and arrhythmias)
miller fisher syndrome- triad of ophthmaloplegia (weakness of eye M), areflexia, ataxia. present with descending sx and associated with anti-GQ1b ab.
MRI: enhanced nerve roots
LP- albuminocytologic dissocation
Tx: IVIG and plasmapharesis. former is easier with less SE. no steroids. supportive care bc 30% dev NM respiratory failure- need mechanical ventilation. DVT pox, bowel and bladder care, PT/OT, pain ctrl, psych support
conduction block, decr v- demyelinating. decr amplitude- axonal process
AI, 20-50yo, presided by respiratory or intestinal infection
ulnar N injruy
travel around posterior aspect of medial epicondyle. so if strike that, may injure. parathesiae in 4th and 5th digit or claw hand
extend wrist. sensation on dorsal hand
carpal tunnel syndrome
compression of median N in wrist. C6, 7, 8, T1 roots. pain and paresthesias in digit 1-3, half of 4, thinner eminence atrophy. clumsiness while hold obj, difficulty opening door knobs and jar lids. can awaken pt from sleep and feels better when shake hand. pain may radiate in arm or forearm.
elecit pain by gently banging on wrist. for carpel tunnel
elect pain by prolong wrist flexion. for carpel tunnel
in carpel tunnel pt, evaluate for
preg, endocrinopathies- diabetes, thyroid and GH. acromegaly
carpel tunnel tx
splints at night and avoidance of repetitive mvt. release of transve carpal ligament
radial N injury
radial nerve via triceps
weakness of middle, index, thumb from median N injury
femoral N injury
weakness of knee extension and hip flexion and sensory loss over anterior medial aspect of thigh, medial shin, arch of foot.
lateral femoral cutaneous N syndrome
meralgia parethetica. compression of N as exit inguinal lig. only sensory sx on lateral thigh. tx with wt loss and looser clothes.
superficial radial N branch compression mononeuropathy due to tight fitting handcuff. sensory loss on back of thumb
characterize foot drop. drag toe along ground or bend knees to lift foot higher than usual to avoid dragging.
foot drop associated diseases. N
ALS, MS, PD. injure deep peroneal N
deep peroneal N
sensation of lateral calf and foot. fall asleep with leg crossed get numbers there.
foot plantar flexion
hamstring M/knee flexion
C6 root injury
shooting pain from neck to thumb. decr sensation of them. decr biceps reflex and weakness of biceps M
ankel jerk reflex
stocking glove peripheral neuropathy
caused by alcohol, diabetes, Multiple myeloma (screen for this if no obvious cause of sx)
GBS, transverse myelitis, tick paralysis, spinal cord tumor
duschende muscular distrophy
pseudohypertrophy- M infiltrated by fatty tissue, dilated cardiomyopathy, mild mental retardation. dystrophin mut- can't connect M fiber to extracellular matrix through cell mem. congenital- x-linked recessive.
lab: CK lvl 100x above norm
tx: avoid exercise- injure M, weekly steroids. small deletion but shifted reading frame
3-5yo trouble walking, 13yo- wheelchair bound. mid-20s-die
milder than DMD. walk into early adulthood. large deletion but intact reading frame
common cause of myopathies at high doses. elevated CK. hx of M pain and aches
chronic use produces a slowly progressive proximal myopathy
inclusion body myositis
>50yo. weakness, assymetrical in distal M. CK normal or moderatly incr. neuro degen of M wo effective tx
immune mediated info that destroy M fibers.
post synaptic membrane defect
more consistent with MG and show fatiguability
inclusion body myositis, polymyositis, dermatomyositis. uncommon. associated with info infiltrates on biopsy
>18yo. subacute inflm myopathy- associated with AI. CK 50x normal. tx- oral steroids + immunosuppressants like azathioprine, methotrexate or IVIG
adult and children. heliotrope rash, erythema on knocks -gottron sign, knees, elbow, neck and shoulder= shwls sign. hands can be scaly- mechanics hands. 15% associated with cancer.
tx as polymyositis
raynaud's phenomenon- vasospams in finger and anti-jo-1 ab.
more epic of temporal arteritis.
HA, fever, blurred or sudden loss of vision.
incr ESR then tx with prednisone
hyperkalemic periodic paralysis
auto dom disease of na ch. serum and urinary K high during attacks. present bf 10 with proximal M weakness provoke by cold, exercise, K rick foods (Juice). tx: acetazolamide
hypokalemic periodic paralysisi
autosomal dom disease of ca-ch. present in early childhood with acute epic of soreness in back, thigh, limbs. epi last for several hr, start and end abruptly
broke by resting after exercise and carbs. tx with oral K supplement
ragged red m fibers. abn accumulation in mito. CSF or serum lactate and pyruvate elevation