LAUSR

Poison hemlock (Conium maculatum) is a common weed that grows throughout the United States. Accidental poisonings from poison hemlock caused by misidentification have occasionally been reported.[1] The piperidine alkaloids, coniine, c-coniceine and N-methylconiine account for most of the plant’s toxic effects.[2] These alkaloids possess nicotine-like effects on both autonomic receptors and skeletal muscle, and usually produce biphasic nicotinic effects, including salivation, fasciculation, mydriasis and tachycardia followed by bradycardia and muscular paralysis.[3] A 45 years-old, previously healthy husband and wife, both ingested unknown amount of “wild celery” (Figure 1), foraged from a regional park. They cooked the stems and leaves along with tomato, eggs and rice. Approximately one hour after ingestion, they presented to the emergency department complaining of nausea, perioral numbness, dizziness, blurred vision and limb weakness. Both patients were afebrile with the following vital signs, husband: heart rate (HR), 58 beats/min, blood pressure (BP), 114/71mmHg and respiratory rate (RR), 16 breaths/min; wife: HR 77 beats/min, BP 125/75mmHg, RR 16 breaths/min. Their physical examinations including pupil sizes, oral mucosa and neuromuscular examination did not reveal any notable abnormality. Laboratory data for both the patients were also unremarkable. The husband received intravenous fluids and oral activated charcoal, and his symptoms resolved eight hours postingestion. The wife developed respiratory arrest and became unresponsive several minutes after her arrival. She was intubated and ventilated mechanically. A head computed tomography was performed and was normal. Urine drug screening, testing for eight common drugs of abuse, was also negative. She recovered rapidly with supportive care, was successfully extubated on hospital day two, and was subsequently discharged on hospital day four without sequelae. The admission blood specimen of the husband was sent to a reference laboratory for confirmatory testing using liquid chromatography time-of-flight mass spectrometry (AB Sciex Triple TOF 5600). The sample was positive for both coniine and c-coniceine confirming the exposure. Unfortunately, the admission sample of the wife was not available for analysis. A blood sample from hospital day two was tested instead, and the results were negative.