A 6-year-old boy presents with his father to the emergency department for excessive salivation, watery eyes, and uncontrolled defecation which started suddenly one hour ago. The father states that he found his son playing in the medicine cabinet and worries that he may have consumed some of the father’s pills. The father takes medications for hypertension and myasthenia gravis. The patient does not have any significant past medical history. The patient’s vital signs reveal bradycardia. Physical examination reveals excessive salivation and watery eyes. Auscultation of the abdomen reveals growling and rumbling sounds though there is no tenderness to palpation.
Which of the following additional findings is most likely present in this patient?
E) Pinpoint pupils
This patient is likely suffering from a cholinergic crisis secondary to consuming medication for myasthenia gravis medication (e.g., acetylcholinesterase agents such as pyridostigmine). Symptoms of a cholinergic crisis can be remembered by the mnemonic SLUDGE, for Salivation, Lacrimation, Urination, Defecation, and Gastrointestinal upset, and Emesis. The growling or rumbling sounds in the abdomen is called borborygmi. Excessive parasympathetic activity also results in pinpoint pupils and bradycardia.
Answer choice A: Dilated pupils, is incorrect. This would be a feature of a sympathomimetic crisis. The parasympathetic activity of a cholinergic crisis is more likely to yield pinpoint pupils, which can also be found in opiate overdose.
Answer choice B: Dry skin, is incorrect. This is more commonly a feature of an anticholinergic crisis, which is often remembered by the mnemonic “Hot as a hare, blind as a bat, dry as a bone, red as a beet, and mad as a hatter” to remember hyperthermia, mydriasis and blurred vision, dry skin and mucous membranes, flushing, and altered mental status, agitation, and paranoia. A cholinergic crisis, by contrast, causes excessive bodily secretions.
Answer choice C: Elevated blood pressure, is incorrect. This is more commonly a feature of a sympathomimetic crisis. This patient experiencing a cholinergic crisis is more likely to experience excessive parasympathetic activity.
Answer choice D: Elevated temperature, is incorrect. Hyperthermia is more commonly a feature of an anticholinergic crisis, which is often remembered by the mnemonic “Hot as a hare, blind as a bat, dry as a bone, red as a beet, and mad as a hatter”.
Key Learning Point
A cholinergic toxidrome is characterized by excessive salivation, lacrimation, urination, defecation, gastrointestinal activity, bradycardia, and pinpoint pupils. Cholinergic crisis can result from overdose of acetylcholinesterase inhibitors such as those used to treat myasthenia gravis.