Ackee Fruit Toxicity

Ackee fruit grows mostly in the Caribbean islands and West Africa. The unripe fruit contains hypoglycin A. A metabolite of hypoglycin A binds to carnitine and coenzyme A, making them unavailable for metabolic reactions. Lack of these enzymes leads to inability to perform gluconeogenesis.

When ackee fruit is allowed to fully ripen and is fully cooked, it is safe for consumption. Cooked ackee fruit is often served with fish in Jamaican meals. Toxicity occurs when unripe ackee fruit or the water in which unripe ackee fruit is cooked is ingested. This often occurs in epidemics in times of economic hardship. Ackee fruit which is forcibly opened is also toxic, as there is toxin in the covering of the seeds. When the fruit ripens, it opens naturally.

Clinical presentation: The main clinical effects are hypoglycemia, severe vomiting, and seizures. There is usually a period of several hours after ingestion marked by mild abdominal discomfort before onset of vomiting. There is usually a second bout of vomiting several hours later, accompanied by seizures and marked hypoglycemia (up to 3mg/dL has been reported). If a large amount of the toxin is ingested, symptoms can begin quickly, within minutes. Mortality in severe untreated toxicity is 80% in some series.

Treatment: Mainly supportive. Dextrose infusion, benzodiazepines, and anti-emetics should be given. Endotracheal intubation is often needed for airway control in severe cases. Activated charcoal may be given if the patient presents soon after ingestion.

Several other therapies have a theoretical benefit but there are no data in humans: carnitine may be helpful similar to valproate toxicity; methylene blue has a theoretical benefit but animal studies show glucose infusion alone to be equivalent; glucagon and octreotide may be helpful.

By Dr. Nathan Reisman

Reference: Reisman N, Wiener SW. Hypoglycemic Plant Poisoning. Medscape Reference. Updated November 12, 2013. Available at: http://emedicine.medscape.com/article/817325-overview.