Anabasine toxicity from a topical folk remedy

Ingestion of A Common Plant's Leaves Leads to Acute Respiratory Arrest and Paralysis: A Case Report

Background

Nicotiana glauca is a plant known to cause acute toxicity upon ingestion or dermal exposure due to the nicotinic alkaloid, anabasine. Nicotinic alkaloids cause toxicity by acting as agonists on nicotinic-type acetylcholine receptors (nAChRs). Initial stimulation of these receptors leads to symptoms such as tachycardia, miosis, and tremors. The effects of high doses of nicotinic alkaloids are biphasic, and eventual persistent depolarization of nAChRs at the neuromuscular junction occurs. This causes apnea, paralysis, and cardiovascular collapse.

Case Report

In this report, we present a case of respiratory arrest due to nicotinic alkaloid poisoning from the ingestion of Nicotiana glauca. The diagnosis was suspected after the patient’s family gave a history of the patient ingesting a plant prior to arrival. They were able to also provide a physical sample of the plant.

Conclusion

The phone application, “Plant Snap”, determined the plant species and helped confirm the diagnosis. This case describes how modern technology and thorough history taking can combine to provide the best possible patient care.

Respiratory Failure Due To Plant Poisoning: Nicotiana glauca Graham

BACKGROUND

Cases of human poisoning associated with Nicotiana glauca Graham are quite rare. Patients may consume the plant by mistaking it for spinach or use it as a folk remedy. The toxin stimulates the acetylcholine receptors in the central and autonomic nervous systems. A prompt and appropriate supportive treatment is crucial for survival.

CASE REPORT

A 72-year-old female with a known breast cancer was brought to our emergency department (ED) with complaints of nausea and vomiting. The patient stated that her complaints started 2 h after she had cooked and eaten a plant in the hopes that it would help cure her cancer. On the second hour after arrival, the patient became confused. It was observed that the chest wall movements had decreased and that the patient had difficulty breathing. Due to respiratory failure, orotracheal intubation was performed to secure the airway. A sample of the plant that was eaten was requested from the patient's relatives. According to an Internet search, the plant sample was identified as N. glauca Graham. The patient was diagnosed with N. glauca Graham poisoning. The patient was extubated after 30 h. On 3-month follow-up, the patient was neurologically intact and had no complaints related to poisoning. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Patients with incurable diseases such as cancer tend to try folk remedies and can end up in ED. In patients who present with muscle paralysis and respiratory failure, emergency physicians should consider N. glauca Graham as a cause of plant poisoning.

Poisoning Through Pediatric Skin: Cases from the Literature

Poisoning through pediatric skin leading to acute systemic symptoms is a relatively uncommonly reported phenomenon. Systemic toxicity through the skin typically occurs by direct contact between therapeutic or non-therapeutic topical agents and the skin. Though uncommon, poisoning through pediatric skin can have significant consequences and must be recognized so the offending agent may be discontinued and appropriate treatment initiated. We performed a literature search for all article types between 1950 and April 2016 to provide a single source of detectable cases of acute toxicity in pediatric patients due to percutaneous exposure. This literature review discusses relevant pediatric skin physiology along with reports of poisoning events that resulted in systemic signs and symptoms and even death to provide a comprehensive report on causes of pediatric poisoning through the skin.

Nicotine Elicits Convulsive Seizures by Activating Amygdalar Neurons

Nicotinic acetylcholine (nACh) receptors are implicated in the pathogenesis of epileptic disorders; however, the mechanisms of nACh receptors in seizure generation remain unknown. Here, we performed behavioral and immunohistochemical studies in mice and rats to clarify the mechanisms underlying nicotine-induced seizures. Treatment of animals with nicotine (1–4 mg/kg, i.p.) produced motor excitement in a dose-dependent manner and elicited convulsive seizures at 3 and 4 mg/kg. The nicotine-induced seizures were abolished by a subtype non-selective nACh antagonist, mecamylamine (MEC). An α7 nACh antagonist, methyllycaconitine, also significantly inhibited nicotine-induced seizures whereas an α4β2 nACh antagonist, dihydro-β-erythroidine, affected only weakly. Topographical analysis of Fos protein expression, a biological marker of neural excitation, revealed that a convulsive dose (4 mg/kg) of nicotine region-specifically activated neurons in the piriform cortex, amygdala, medial habenula, paratenial thalamus, anterior hypothalamus and solitary nucleus among 48 brain regions examined, and this was also suppressed by MEC. In addition, electric lesioning of the amygdala, but not the piriform cortex, medial habenula and thalamus, specifically inhibited nicotine-induced seizures. Furthermore, microinjection of nicotine (100 and 300 μg/side) into the amygdala elicited convulsive seizures in a dose-related manner. The present results suggest that nicotine elicits convulsive seizures by activating amygdalar neurons mainly via α7 nACh receptors.

A systematic review of the reporting of adverse events associated with medical herb use among children

PURPOSE

Information about the safety of herbal medicine often comes from case reports published in the medical literature, thus necessitating good quality reporting of these adverse events. The purpose of this study was to perform a systematic review of the comprehensiveness of reporting of published case reports of adverse events associated with herb use in the pediatric population.

METHODS

Electronic literature search included 7 databases and a manual search of retrieved articles from inception through 2010. We included published case reports and case series that reported an adverse event associated with exposure to an herbal product by children under the age of 18 years old. We used descriptive statistics. Based on the International Society of Epidemiology's "Guidelines for Submitting Adverse Events Reports for Publication," we developed and assigned a guideline adherence score (0-17) to each case report.

RESULTS

Ninety-six unique journal papers were identified and represented 128 cases. Of the 128 cases, 37% occurred in children under 2 years old, 38% between the ages of 2 and 8 years old, and 23% between the ages of 9 and 18 years old. Twenty-nine percent of cases were the result of an intentional ingestion while 36% were from an unintentional ingestion. Fifty-two percent of cases documented the Latin binomial of the herb ingredients; 41% documented plant part. Thirty-two percent of the cases reported laboratory testing of the herb, 20% documented the manufacturer of the product, and 22% percent included an assessment of the potential concomitant therapies that could have been influential in the adverse events. Mean guideline adherence score was 12.5 (range 6-17).

CONCLUSIONS

There is considerable need for improvement in reporting adverse events in children following herb use. Without better quality reporting, adverse event reports cannot be interpreted reliably and do not contribute in a meaningful way to guiding recommendations for medicinal herb use.

Nicotiana glauca (tree tobacco) intoxication--two cases in one family

We present two cases of rare human poisoning in one family following ingestion of cooked leaves from the tobacco tree plant, Nicotiana glauca. The toxic principle of N. glauca, anabasine (C10H14N2), is a small pyridine alkaloid, similar in both structure and effects to nicotine, but appears to be more potent in humans. A 73-year-old female tourist from France, without remarkable medical history, collapsed at home following a few hours long prodrome of dizziness, nausea, vomiting, and malaise. The symptoms developed shortly after eating N. glauca cooked leaves that were collected around her daughter's house in Jerusalem and mistaken for wild spinach. She was found unconscious, with dilated pupils and extreme bradycardia. Following resuscitation and respiratory support, circulation was restored. However, she did not regain consciousness and died 20 days after admission because of multi-organ failure. Anabasine was identified by gas chromatography/mass spectrometry method in N. glauca leaves and in the patient's urine. Simultaneously, her 18-year-old grandson developed weakness and myalgia after ingesting a smaller amount of the same meal. He presented to the same emergency room in a stable condition. His exam was remarkable only for sinus bradycardia. He was discharged without any specific treatment. He recovered in 24 h without any residual sequelae. These cases raise an awareness of the potential toxicity caused by ingestion of tobacco tree leaves and highlight the dangers of ingesting botanicals by lay public. Moreover, they add to the clinical spectrum of N. glauca intoxication.

Nicotinic plant poisoning

INTRODUCTION

A wide range of plants contain nicotinic and nicotinic-like alkaloids. Of this diverse group, those that have been reported to cause human poisoning appear to have similar mechanisms of toxicity and presenting patients therefore have comparable toxidromes. This review describes the taxonomy and principal alkaloids of plants that contain nicotinic and nicotinic-like alkaloids, with particular focus on those that are toxic to humans. The toxicokinetics and mechanisms of toxicity of these alkaloids are reviewed and the clinical features and management of poisoning due to these plants are described.

METHODS

This review was compiled by systematically searching OVID MEDLINE and ISI Web of Science. This identified 9,456 papers, excluding duplicates, all of which were screened. Reviewed plants and their principal alkaloids. Plants containing nicotine and nicotine-like alkaloids that have been reported to be poisonous to humans include Conium maculatum, Nicotiana glauca and Nicotiana tabacum, Laburnum anagyroides, and Caulophyllum thalictroides. They contain the toxic alkaloids nicotine, anabasine, cytisine, n-methylcytisine, coniine, n-methylconiine, and gamma-coniceine.

MECHANISMS OF TOXICITY

These alkaloids act agonistically at nicotinic-type acetylcholine (cholinergic) receptors (nAChRs). The nicotinic-type acetylcholine receptor can vary both in its subunit composition and in its distribution within the body (the central and autonomic nervous systems, the neuromuscular junctions, and the adrenal medulla). Agonistic interaction at these variable sites may explain why the alkaloids have diverse effects depending on the administered dose and duration of exposure.

TOXICOKINETICS

Nicotine and nicotine-like alkaloids are absorbed readily across all routes of exposure and are rapidly and widely distributed, readily traversing the blood-brain barrier and the placenta, and are freely distributed in breast milk. Metabolism occurs predominantly in the liver followed by rapid renal elimination.

CLINICAL FEATURES

Following acute exposure, symptoms typically follow a biphasic pattern. The early phase consists of nicotinic cholinergic stimulation resulting in symptoms such as abdominal pain, hypertension, tachycardia, and tremors. The second inhibitory phase is delayed and often heralded by hypotension, bradycardia, and dyspnea, finally leading to coma and respiratory failure.

MANAGEMENT

Supportive care is the mainstay of management with primary emphasis on cardiovascular and respiratory support to ensure recovery.

CONCLUSIONS

Exposure to plants containing nicotine and nicotine-like alkaloids can lead to severe poisoning but, with prompt supportive care, patients should make a full recovery.