A 34-year-old man comes to the emergency department due to difficulty swallowing and blurred vision that started last night. He also reports having mild shortness of breath that started today. The patient returned to his home in Connecticut yesterday from a 7-day Caribbean trip during which he snorkeled, ate locally cured fish, and hiked in a forest. He had a mild upper respiratory illness 2 weeks ago that spontaneously resolved; otherwise, he has no other medical problems. The patient does not use tobacco, alcohol, or illicit drugs. Temperature is 37 C (98.6 F), blood pressure is 115/70 mm Hg, and pulse is 88/min. His oral mucosa is dry and speech is slurred. Pupils are dilated and react sluggishly to light. Neck muscles are weak and he has difficulty holding his head up. Muscle strength is 1/5 in the bilateral upper limbs and 5/5 in the lower limbs. There are no sensory abnormalities. Which of the following is the most appropriate next step in management of this patient?

Question

A 34-year-old man comes to the emergency department due to difficulty swallowing and blurred vision that started last night.  He also reports having mild shortness of breath that started today.  The patient returned to his home in Connecticut yesterday from a 7-day Caribbean trip during which he snorkeled, ate locally cured fish, and hiked in a forest.  He had a mild upper respiratory illness 2 weeks ago that spontaneously resolved; otherwise, he has no other medical problems.  The patient does not use tobacco, alcohol, or illicit drugs.  Temperature is 37 C (98.6 F), blood pressure is 115/70 mm Hg, and pulse is 88/min.  His oral mucosa is dry and speech is slurred.  Pupils are dilated and react sluggishly to light.  Neck muscles are weak and he has difficulty holding his head up.  Muscle strength is 1/5 in the bilateral upper limbs and 5/5 in the lower limbs.  There are no sensory abnormalities.  Which of the following is the most appropriate next step in management of this patient?

Quizplus · Accepted Answer

11ec25c8_d47c_fa5d_bc81_272e17fe2159_MD0003_00 This patient likely has foodborne botulism, a potentially life-threatening illness caused by the ingestion of food contaminated with botulinum toxin formed through germination of Clostridium botulinum spores. Improperly canned foods and cured fish provide the appropriate environment for spore germination. Ingestion results in absorption of a preformed toxin that inhibits presynaptic acetylcholine release at the neuromuscular junction. Symptoms develop acutely (within 36 hours) following toxin ingestion. Prodromal symptoms can include gastrointestinal discomfort, dry mouth, and sore throat. Patients classically develop bilateral cranial neuropathies often leading to blurred vision (due to fixed pupillary dilation), diplopia, facial weakness, dysarthria, and dysphagia. Symmetric descending muscle weakness usually follows, initially affecting the upper extremities and trunk and then the lower extremities. Respiratory failure requiring mechanical ventilation can occur secondary to diaphragmatic paralysis. Patients with suspected foodborne botulism should be checked for toxin in the blood. In addition to supportive care, treatment for adults and children age >1 involves passive immunity through administration of horse-derived antitoxin. (Choice A) Atropine and pralidoxime are used to treat cholinergic toxicity (eg, bradycardia, miosis, bronchospasm, vomiting, diarrhea) caused by organophosphate poisoning. Atropine blocks the peripheral effects of acetylcholine at muscarinic receptors, whereas pralidoxime aids in the reactivation of acetylcholinesterase. (Choice B) Edrophonium is a short-acting acetylcholinesterase inhibitor that temporarily improves muscle weakness in patients with myasthenia gravis, aiding in the diagnosis. In men, myasthenia gravis usually presents in the sixth to eighth decade with fluctuating and fatigable weakness of the ocular (eg, diplopia, ptosis) and bulbar (eg, fatigable chewing) muscles. Symptoms worsen with activity or near the end of the day. (Choice D) Intravenous corticosteroids (eg, methylprednisolone) may be indicated during an acute exacerbation of multiple sclerosis, which typically presents in women age 15-50 with neurologic deficits (eg, optic neuritis, internuclear ophthalmoplegia, transverse myelitis) disseminated in space and time. (Choice E) Tick paralysis is caused by a neurotoxin present in tick saliva and typically presents with paresthesias and fatigue followed by ascending muscle paralysis. Affected patients should have their skin thoroughly examined as tick removal can improve symptoms within a few hours. (Choice F) Therapeutic plasma exchange (plasmapheresis) is indicated for the treatment of Guillain-Barré syndrome and myasthenic crisis. Guillain-Barré syndrome usually presents with rapidly progressive ascending muscle paralysis and areflexia following an infection (eg, Campylobacter jejuni, viruses), whereas myasthenic crisis is characterized by severe respiratory muscle weakness and respiratory failure. Educational objective: Foodborne botulism is a potentially life-threatening illness caused by the ingestion of food (eg, improperly canned fruits/vegetables, cured fish) contaminated with botulinum toxin. Symptoms typically occur within 36 hours of ingestion and begin with bilateral cranial neuropathies followed by symmetric descending muscle weakness. References: Food-borne botulism. (http://www.ncbi.nlm.nih.gov/pubmed/22894077)

A 34-Year-Old Man Comes to the Emergency Department Due to Difficulty