Snapshot A 35-year-old banker presents to the ED after hitting his head when he tripped while climbing the subway stairs. He has noted his legs feeling heavy over the last 5 days and reported trouble pushing himself up afterthe fall. Rnausea, vomiting, and diarrhea 3 days ago (admits to eating discount sushi). Exam is remarkable for symetric 3/5 lower and upper extremity weakness, absent ankle and patellar reflexes and 1+ biceps reflex. He is only able to count to 10 in one breath. Routine labs, chest x-ray, and head CT are unrevealing. Introduction Acute acquired demyelinating disease involving peripheral nerves, cranial nerves, and nerve roots Includes acute axonal variants (Aute Motor Axonal Neuropathy, Acute Sensory Motor Axonal Neuropathy) Often preceded by viral, bacterial illness or vaccination campylobacter jejuni most frequently indentified preceding infection mycoplasma and herpes family viruses less frequently Epidemiology Incidence approximately 1/100,000 per year in the US Occurs from infants to the very elderly attack rates highest ages 50-70 no clear gender predominance Presentation Symptoms typically evolve days to 1-2 weeks symetrical ascending weakness pain and weakness in hip, thighs, and back which precede weakness episodic diaphoresis Physical exam areflexia autonomic dysfunction sinus tachycardia labile blood pressure reduced distal proprioception, vibration sensation bilateral CN VII palsy symetrical or sequential urinary retention Fisher variant opthalmoplegia, areflexia, with or without ataxia and/or weakness Evaluation Lumbar puncture albumin cytologic disassociation elevated protein mostly acellular (or with low lymphocytic predominance) occurs in the late first week other CSF serologies typically normal Nerve conduction studies slowed conduction velocity reduced amplitude in compound muscle action potentials reduced amplitude with relatively preserved conduction velocity implicates axonal neuropathy delayed/absent F waves implicates nerve root involvement delayed/absent H reflex correlates with decreased/absent ankle reflex MRI cauda equina gandolinium enhancement in acute cases DIfferential Diagnosis Myasthenia gravis, ALS, infectious myelitis (Polio, West Nile, other enteroviruses), paralytic porphyria, heavy metal poisoning, toxin ingestion (botulism, ciguatoxin, tetrodotoxin), tick paralysis, multiple sclerosis, carcinomatous meningitis Treatment Plasmaphoresis best effect if initiated within first 2 wks roughly halves hospital course adverse effects: hypotension arrhythmias hypoprothrombinemia consider checking fibrinogen level between treatments IVIG similar effeciacy compared to plasmaphoresis adverse effects: headache aseptic meningitis renal failure anaphylaxis patients with congenital IgA deficiency Consider plasmaphoresis followed by IVIG in relapsing cases Corticosteriods have questionable benefit No additive benefit when combining plasmaphoresis and IVIG Prognosis, Prevention, and Complications With treatment and respiratory support, the prognosis is promising: 80-90% have complete recovery 10% have pronounced disability 2-5% mortality rate 5-10% recurrence Typical recovery take weeks to months recovery from axonal variant may take over a year 35 year old banker presents to the ED after hitting his head when he tripped while climbing the subway stairs. He has noted his legs feeling heavy over the last 5 days and reported trouble pushing himself up afterthe fall. Rnausea, vomiting, and diarrhea 3 days ago (admits to eating discount sushi). Exam is remarkable for symetric 3/5 lower and upper extremity weakness, absent ankle and patellar reflexes and 1+ biceps reflex. He is only able to count to 10 in one breath. Routine labs, chest x-ray, and head CT are unrevealing.