Scorpion Bite-presentation and management
Scorpions are arachnids that feed on ground-dwelling arthropods and small lizards. They paralyze their prey and defend themselves by injecting venom from a stinger on the tip of the tail.
Scorpions are nocturnal and remain hidden during the day in crevices or burrows or underwood, loose bark, or rocks. They occasionally enter houses and tents and may hide in shoes, clothing, or bedding.
Scorpions sting humans only when threatened.
Management of scorpion bite
Identification of the offending scorpion helps to determine the course of treatment. Painful but relatively harmless scorpion stings need to be distinguished from the potentially lethal envenomation’s that are produced by ~30 of the ~1000 known species and that cause more than 5000 deaths worldwide each year.
Aggressive supportive care and judicious use of antivenom can reduce or eliminate deaths from more severe envenomations. Keeping the patient calm and applying pressure dressings and cold packs to the sting site are measures that decrease the absorption of venom.
Although effective, cost analyses suggest that antivenoms should be reserved for only the most severe envenomations.
| Country | Common species | Presentation (Envenomation) |
| Unites States | Centruroides sculpturatus (C. exilicauda) | Neurotoxicity-a) A little swelling, but prominent pain, paresthesia, and hyperesthesia.
(Tap test- These symptoms can be accentuated by tapping on the affected area. ) b) Cranial nerve dysfunction c) Hyperexcitability of skeletal muscles d) Restlessness, blurred vision, abnormal eye movements, profuse salivation, lacrimation, rhinorrhea, slurred speech, difficulty in handling secretions, diaphoresis, nausea, and vomiting. e) Fatal respiratory arrest |
| · Middle East and North America
· India · Brazil |
· Leiurus quinquestriatus
· Mesobuthus tamulus · Tityus serrulatus |
Hypertensive Crises-(massive release of endogenous catecholamines )
a) Hypertension b) Arrhythmias c) Pulmonary edema d) Myocardial damage. |
| Iran | Hemiscorpius lepturus. | Tissue necrosis and hemolysis |
| Trinidad | Tityus trinitatis | Acute pancreatitis |
| —————— | Nonpoisonous species | Immediate sharp local pain followed by edema, ecchymosis, and a burning sensation. |
Management
| Nonpoisonous bite (Local site management) | Ice packs, analgesics, or antihistamines.
Because most victims experience only local discomfort, they can be managed at home with instructions to return to the emergency department if signs of cranial-nerve or neuromuscular dysfunction develop. IV administration of antivenom rapidly reverses cranial-nerve dysfunction and muscular symptoms. |
| Neurotoxicity | Close monitoring and aggressive supportive care.A continuous IV infusion of midazolam controls the agitation, flailing, and involuntary muscle movements produced by scorpion stings |
| Hypertensive crises
Pulmonary edema |
NifedipineNitroprusside
Hydralazine Prazosin |
| Bradyarrythmias | Atropine |
LATEST UPDATE: (NOV 2023) -Novel therapeutic formulation developed for improved treatment of Indian red scorpion sting.
The Indian red scorpion (Mesobuthus tamulus), with its life-threatening sting, is one of the world’s most dangerous scorpions.
Intravenous administration of equine anti-scorpion antivenom (ASA), raised against M. tamulus venom (MTV), is the only available treatment for scorpion stings. However, the low proportion of venom-specific antibodies against the most abundant low molecular mass channel toxin is a barrier to efficient clinical management of scorpion sting patients. Therefore, the high antivenom requirement may lead to adverse serum reactions in treated patients.
Scorpion envenomation and its treatment needs extensively research and alternative therapies.
Conventionally, α1- adrenoreceptor agonist (AAAs), such as Prazosin, is also used alone or in combination with commercial ASA for the treatment of stung patients; however, this therapy is less effective and associated with certain limitations.
To solve this critical issue, a team of scientists from the Institute of Advanced Study in Science and Technology (IASST), an autonomous institute of the Department of Science and Technology as well as researchers from Tezpur University & NIELIT, Guwahati have invented novel therapeutic drug formulations (TDF) comprised of low doses of commercial ASA, AAA, and vitamin C, for inhibiting the Indian red scorpion venom-induced toxicity and associated symptoms.
A new therapeutic drug formulation (TDF) comprising of low doses of commercial equine anti-scorpion antivenom (ASA), α1- adrenoreceptor agonist (AAAs) and vitamin C, for inhibiting the Indian red scorpion venom-induced toxicity and associated symptoms can help improve clinical management of scorpion sting patients.
The novel TDF efficiently neutralized the Indian red scorpion venom, induced increase in blood glucose level, organ tissue damage, necrosis, and pulmonary edema in Wistar rats, much better than commercial ASA, AAA, and vitamin C.
The treatment holds promise for effective treatment against scorpion stings and will save the lives of millions of patients worldwide.
