EM · Toxicology and environmental emergencies

Spider and marine envenomation

Also known as Latrodectism · Red-back spider bite · Funnel-web spider bite · Box jellyfish sting · Chironex fleckeri envenomation · Irukandji syndrome · Blue-ringed octopus envenomation · Tetrodotoxin poisoning

ANZ spider and marine envenomation — five syndromes the Fellowship candidate must hold as patterns. Latrodectism (red-back) is sustained painful muscle contraction with regional diaphoresis and autonomic surge, driven by alpha-latrotoxin opening presynaptic calcium channels; treatment is analgesia and red-back spider antivenom (efficacy contested). Funnel-web spider envenomation is the only ANZ spider that kills — fasciculations, profuse sweating, hypertension, pulmonary oedema and catecholamine cardiomyopathy from robustoxin blocking neuronal sodium channels; first aid is pressure immobilisation and treatment is funnel-web antivenom two vials intravenously, repeated. Box jellyfish (Chironex fleckeri) sting causes immediate severe pain, ladder-track dermonecrosis and sudden cardiac arrest from pore-forming cardiotoxins; first aid is vinegar then box-jellyfish antivenom. Irukandji syndrome is a delayed catecholamine-surge cardiomyopathy with troponin leak and hypertension. Blue-ringed octopus envenomation is rapid tetrodotoxin flaccid paralysis with an awake patient — supportive ventilation is definitive, there is no antivenom. Differential is snake bite and allergic reaction. ACEM-primary, globally tagged.