Solanaceous steroidal glycoalkaloids and poisoning by Solanum torvum, the normally edible susumber berry

Ingestion of immature, environmentally stressed, or cultivar-specific Solanum species (particularly the potato) has been previously associated with gastrointestinal and neurological symptoms caused by solanaceous steroidal glycoalkaloids (SGAs). We report on two geographically, temporally disparate outbreaks of poisoning by susumber berries (Solanum torvum– Solanaceae) and on detection of alkaloids not present in non-toxic berries. Five family members in New York City participated in a traditional evening meal containing Jamaican susumber berries. All those consuming berries were symptomatic the following morning with varying degrees of gastrointestinal distress, dizziness, slurred speech, cranial nerve deficits, and ataxia. The most seriously afflicted patient developed hypertension, confusion, proximal upper extremity weakness, and hypercapnic respiratory failure requiring prolonged mechanical ventilation. A separate cohort of six patients in Toronto ate unripe Jamaican susumber berries. They presented 14 h post-ingestion with varying degrees of diarrhea, weakness, facial paralysis, slurred speech, ataxia, early hypertension, and proximal weakness. Two patients had ventilatory decompensation; one required intubation. Poisonous berries appeared indistinguishable from non-toxic varieties. We isolated solasonine, larger amounts of solamargine, and other steroidal glycoalkaloids in the toxic berry strains. S. torvum poisoning can produce significant neurological and gastrointestinal effects which appear to be mediated by SGAs present in the berries.