Scorpion envenomation: Difference between revisions
No edit summary |
|||
| (14 intermediate revisions by 8 users not shown) | |||
| Line 1: | Line 1: | ||
== Background == | ==Background== | ||
*Most scorpion stings in North America result only in local pain. | |||
*Arizona Bark Scorpion (''Centruroides sculpturatus''), found in AZ, NV, NM, TX, and CA, is the only neurotoxic species found in North America and can cause systemic toxicity.<ref name="Boyer" /> | |||
[[File:Bbasgen-bark-scorpion.jpg|thumb|Arizona Bark Scorpion, (''Centruroides sculpturatus'')]] | [[File:Bbasgen-bark-scorpion.jpg|thumb|Arizona Bark Scorpion, (''Centruroides sculpturatus'')]] | ||
==Pathophysiology== | ===Pathophysiology=== | ||
Four neurotoxins | *Four neurotoxins (toxins I to IV) have been isolated from ''C. exilicauda'' | ||
*Toxins target excitable membranes, especially at the neuromuscular junction, by opening sodium channels → repetitive depolarization of nerves in both sympathetic and parasympathetic nervous systems → catecholamine and acetylcholine release.<ref>Nelson, Lewis, and Lewis R. Goldfrank. Goldfrank's Toxicologic Emergencies. New York: McGraw-Hill Medical Division, 2014. Print.</ref> | |||
==Clinical Features== | ==Clinical Features== | ||
[[File:PMC4395898 40409 2014 85 Fig2 HTML.png|thumb|Local scorpion sting (''Rhopalurus amazonicus Lourenço'', Brazil).]] | |||
===Local reaction=== | ===Local reaction=== | ||
*Pain and paresthesias near envenomation site. | *Pain and [[paresthesias]] near envenomation site. | ||
** "Tap" test: severe local tenderness when affected area is lightly tapped | **"Tap" test: severe local tenderness when affected area is lightly tapped | ||
===Systemic reaction=== | ===Systemic reaction=== | ||
*Uncommon but can be severe, particularly in children | *Uncommon but can be severe, particularly in children | ||
*Cranial nerve and somatic motor dysfunction can develop: | *[[Cranial nerve palsies]] and [[weakness|somatic motor dysfunction]] can develop: | ||
**Abnormal roving eye movements, blurred vision, pharyngeal muscle incoordination | **Abnormal roving eye movements, blurred vision, pharyngeal muscle incoordination | ||
**Tongue fasciculations and uncoordinated motor agitation (flailing or jerking extremities) | **Tongue fasciculations and uncoordinated motor agitation (flailing or jerking extremities) | ||
*Tachycardia, other dysautonomias, and severe agitation can also be present | *Hypersalivation, noncardiac [[pulmonary edema]] | ||
**can → [[respiratory distress]]/failure | |||
*[[Tachycardia]], other dysautonomias, and severe agitation can also be present | |||
*Without antivenom, symptoms typically last 24-48 hrs | *Without antivenom, symptoms typically last 24-48 hrs | ||
| Line 32: | Line 37: | ||
{{Bites and stings DDX}} | {{Bites and stings DDX}} | ||
== | ==Evaluation== | ||
*Generally clinical diagnosis | *Generally clinical diagnosis | ||
**Be aware that a discrete scorpion | **Be aware that a discrete scorpion sting mark may not be clinically apparent. | ||
== | ==Management== | ||
*Supportive care | |||
**Cold compress to area of sting | |||
**[[analgesia|Analgesic]] and anti-inflammatory medications | |||
**[[Benzodiazepines]] may help with agitation and muscle spasm | |||
**Intubation for pulmonary symptoms is rare, but may be necessary | |||
*[[Atropine]] | |||
**May be given for hypersalivation and respiratory distress caused | |||
**Contraindicated for scorpion stings not indigenous to US (may exacerbate adrenergic effects) | |||
*Anascorp antivenom (Centruroides immune Fab) - Only stocked by certain hospitals in Arizona, Nevada, and Utah<ref>http://www.anascorp-us.com/hospital/ Accessed 08/03/15</ref> | |||
**Resolves clinical syndrome within 4hr<ref>http://www.fda.gov/ForConsumers/ConsumerUpdates/ucm266515.htm</ref><ref name="Boyer">Boyer LV, Theodorou AA, Berg RA, Arizona Envenomation investigators, et al. Antivenom for critically ill children with neurotoxicity from scorpion stings. N Engl J Med. 2009 May 14;360(20):2090-8.</ref> | |||
**Common side effects: vomiting, pyrexia, rash, nausea, and pruritus | |||
**Serious side effects: anaphylaxis | |||
**Costs approximately $8000 per vial, and requires 3-4 vials for treatment<ref>http://www.azcentral.com/news/articles/2011/11/10/20111110scorpion-drug-cost.html</ref> | |||
==Disposition== | ==Disposition== | ||
| Line 55: | Line 61: | ||
==See Also== | ==See Also== | ||
*[[ | *[[Envenomations, bites and stings]] | ||
== References == | ==References== | ||
<references/> | <references/> | ||
[[Category: | [[Category:Environmental]] | ||
[[Category: | [[Category:Dermatology]] | ||
Revision as of 13:41, 18 July 2020
Background
- Most scorpion stings in North America result only in local pain.
- Arizona Bark Scorpion (Centruroides sculpturatus), found in AZ, NV, NM, TX, and CA, is the only neurotoxic species found in North America and can cause systemic toxicity.[1]
Pathophysiology
- Four neurotoxins (toxins I to IV) have been isolated from C. exilicauda
- Toxins target excitable membranes, especially at the neuromuscular junction, by opening sodium channels → repetitive depolarization of nerves in both sympathetic and parasympathetic nervous systems → catecholamine and acetylcholine release.[2]
Clinical Features
Local reaction
- Pain and paresthesias near envenomation site.
- "Tap" test: severe local tenderness when affected area is lightly tapped
Systemic reaction
- Uncommon but can be severe, particularly in children
- Cranial nerve palsies and somatic motor dysfunction can develop:
- Abnormal roving eye movements, blurred vision, pharyngeal muscle incoordination
- Tongue fasciculations and uncoordinated motor agitation (flailing or jerking extremities)
- Hypersalivation, noncardiac pulmonary edema
- can → respiratory distress/failure
- Tachycardia, other dysautonomias, and severe agitation can also be present
- Without antivenom, symptoms typically last 24-48 hrs
Grades of Centruroides envenomation
- Grade 1 - Local pain and/or paresthesias at site of envenomation
- Grade 2 - Pain and/or paresthesias remote from the site of the sting, in addition to local findings
- Grade 3 - Either cranial nerve/autonomic dysfunction or somatic skeletal neuromuscular dysfunction
- Cranial nerve dysfunction - Blurred vision, roving eye movements, hypersalivation, tongue fasciculations, dysphagia, dysphonia, problems with upper airway
- Somatic skeletal neuromuscular dysfunction - Restlessness, severe involuntary shaking or jerking of the extremities that may be mistaken for a seizure
- Grade 4 - Combined cranial nerve/autonomic dysfunction and somatic skeletal neuromuscular dysfunction
Differential Diagnosis
Envenomations, bites and stings
- Hymenoptera stings (bees, wasps, ants)
- Mammalian bites
- Closed fist infection (Fight bite)
- Dog bite
- Marine toxins and envenomations
- Toxins (ciguatera, neurotoxic shellfish poisoning, paralytic shellfish poisoning, scombroid, tetrodotoxin
- Stingers (stingray injury)
- Venomous fish (catfish, zebrafish, scorpion fish, stonefish, cone shells, lionfish, sea urchins)
- Nematocysts (coral reef, fire coral, box jellyfish, sea wasp, portuguese man-of-war, sea anemones)
- Phylum porifera (sponges)
- Bites (alligator/crocodile, octopus, shark)
- Scorpion envenomation
- Reptile envenomation
- Spider bites
Evaluation
- Generally clinical diagnosis
- Be aware that a discrete scorpion sting mark may not be clinically apparent.
Management
- Supportive care
- Cold compress to area of sting
- Analgesic and anti-inflammatory medications
- Benzodiazepines may help with agitation and muscle spasm
- Intubation for pulmonary symptoms is rare, but may be necessary
- Atropine
- May be given for hypersalivation and respiratory distress caused
- Contraindicated for scorpion stings not indigenous to US (may exacerbate adrenergic effects)
- Anascorp antivenom (Centruroides immune Fab) - Only stocked by certain hospitals in Arizona, Nevada, and Utah[3]
Disposition
- Grade I or II envenomation may generally be discharged after 6 hours of observation in the ED without progression of symptoms.
- Grade III or IV envenomation likely requires antivenom administration and/or admission.
See Also
References
- ↑ 1.0 1.1 Boyer LV, Theodorou AA, Berg RA, Arizona Envenomation investigators, et al. Antivenom for critically ill children with neurotoxicity from scorpion stings. N Engl J Med. 2009 May 14;360(20):2090-8.
- ↑ Nelson, Lewis, and Lewis R. Goldfrank. Goldfrank's Toxicologic Emergencies. New York: McGraw-Hill Medical Division, 2014. Print.
- ↑ http://www.anascorp-us.com/hospital/ Accessed 08/03/15
- ↑ http://www.fda.gov/ForConsumers/ConsumerUpdates/ucm266515.htm
- ↑ http://www.azcentral.com/news/articles/2011/11/10/20111110scorpion-drug-cost.html