Poisoning by toxic plants in Hong Kong: a 15-year review

Introduction: Hong Kong has a great diversity of plants, many of which are toxic to humans.The aim of this study was to identify the plant species most commonly involved in cases of plant poisoning in Hong Kong and to provide clinicians with a reference tool for the diagnosis and management of plant poisoning. Methods:We retrospectively reviewed all plant poisoning cases referred to the Hospital Authority Toxicology Reference Laboratory from 1 January 2003 to 31 December 2017.Demographics, clinical presentation, laboratory findings, treatment and outcomes of patients, as well as morphological identification and analytical testing of the plant specimens, were investigated.Results: A total of 62 cases involving 26 poisonous plant species were identified, among which Alocasia macrorrhizos (Giant Alocasia), Gelsemium elegans (Graceful Jessamine), and Rhododendron (Azalea) species were the three most commonly encountered.Gastrointestinal toxicity (n=30, 48%), neurological toxicity (n=22, 35%), and hepatotoxicity (n=6, 10%) were the three most common clinical problems.Forty-nine (79%) and eight (13%) patients had mild and moderate toxicity, respectively; they all recovered shortly with supportive treatment.The remaining five (8%) patients experienced severe toxicity requiring intensive care support.Most Poisoning by toxic plants in Hong Kong: a 15-year review IntroductionMany plants are poisonous to humans.Surveys of various toxicology centres in Australia, 1 Germany, 2,3 Morocco, 4 New Zealand, 5 Sweden, 6 Thailand, 7 the United Kingdom, 8 and the United States 9,10 showed that plant exposure was responsible for 1.8% to 8% of all inquiries.Most plant exposures did not result in significant toxicity, but severe and life-threatening New knowledge added by this study • The three most common plants causing poisoning in Hong Kong were Alocasia macrorrhizos, Gelsemium elegans, and Rhododendron species.• Plants causing severe and potentially fatal poisonings in Hong Kong were Abrus precatorius, Gelsemium elegans, Rhododendron species, and Emilia sonchifolia.Implications for clinical practice or policy • Plant poisoning is uncommon but can be severe.• Raising public awareness minimises unintentional poisoning.• This study provided useful reference for the local clinicians to diagnose and manage plant poisonings.