Bites And Stings Flashcards
most common response to a Hymenoptera sting is a ___________________ that can last up to several days and generally spontaneously resolves
transient local reaction
Wasps, bees, and ants belong to what order
Hymenoptera
Subgroup which includes the honeybee and bumblebee
Apidae
Subgroup which includes yellow jackets, hornets, and wasps
Vespidae
Subgroup of ants
Formicidae
True or false
Honeybees and bumblebees are usually docile, stinging only when provoked.
A female honeybee is capable of stinging only once (male bees have no stinger) because its stinger has multiple barbs that cause the sting apparatus to detach from the bee’s body, leading to evisceration and eventual death.
True
a known membrane-active polypeptide that can cause degranulation of basophils and mast cells, constitutes >50% of the dry weight of bee venom
Melittin
In Anaphylaxis, Fatalities that occur within the first hour after the sting usually result from _______________ or _____________
airway obstruction
hypotension
General treatment for bee stings
- If the bee stinger is present in the wound, remove it. Immediate removal is the important principle, and the method of removal is irrelevant.
- Wash the sting site thoroughly with soap and water to minimize the potential for infection.
- For local reactions, intermittent application of cold compresses at the site may diminish pain and swelling.
- Oral analgesics, including NSAIDs and antihistamines may limit discomfort and pruritus, respectively.
- If edema is significant, elevation and rest of the affected limb may be beneficial.
corticosteroids: no clear benefit
The venom of the brown recluse contains multiple enzymes, including hyaluronidase and _______________, which is the major enzyme responsible for necrosis
sphingomyelinase D
Identify
brown recluse spider (Loxosceles reclusa)
Close-up look at the characteristic fiddle-shaped back marking. Note the eyes, which are distributed as a single anterior pair and two lateral pairs; the paired eyes are very close together.
Identify
Early brown recluse spider bite (approximately 8 hours old) with a violaceous center surrounded by a faint spreading erythema.
Identify
Black widow spider (Latrodectus mactans) with offspring. Note characteristic hourglass marking on abdomen.
In Latrodectus envenomation, in all cases, the most prominent feature of envenomation is local, regional, or generalized ________ which may be associated with systemic symptoms and autonomic effects.
pain
Describe the clinical syndrome of envenomation is referred to as latrodectism
- pinprick sensation at the bite site,
- increasing local pain that may spread quickly to include the entire bitten extremity.
- Erythema appears approximately 20 to 60 minutes after the bite.
- In some bites, a small, <5-mm erythematous macule develops that may evolve into a larger target lesion with a blanched center and surrounding erythema
- Victims frequently complain of cramp- like spasms in large muscle groups, although physical examination of the “cramping” extremity rarely reveals rigidity.
- The pain often increases progressively, becomes generalized, and can involve the trunk, back, and abdomen.
- Localized diaphoresis near the site of envenomation can be seen.
Identify
Black widow spider bite on the knee
the deadliest spiders in the world
Funnel-web spiders
Treatment for the deadliest spiders
- To reduce venom absorption and systemic toxicity from a bite on an extremity, apply a compressive elastic BANDAGE to the entire length of the limb, and SPLINT extremity to prevent movement.
- IMMOBILIZE the victim and transport promptly to the hospital.
- The specific treatment for systemic toxicity is Funnel-Web Spider Antivenom® (CSL Ltd., Melbourne, Australia). If the patient has signs of systemic toxicity upon arrival or develops them after the compressive elastic bandage is carefully removed, antivenom should be administered until symptoms improve. Antivenom appears effective in reversing many of the manifestations of envenomation and appears to improve mortality. It does not appear effective in reversing cardiac damage.
- Supportive therapy for hypotension (IV fluid), bronchorrhea (atropine), tremors and agitation (benzodiazepines), and hypertension and tachycardia (β-blockers) may be necessary.
ATRAX Symptoms and signs of systemic toxicity
perioral paresthesias
cholinergic excess (nausea, vomiting, diaphoresis, saliva- tion, lacrimation, bronchorrhea)
neuromuscular stimulation (muscle fasciculation, tremors, spasms, weakness)
CNS toxicity (altered level of consciousness)
Myocardial damage with pulmonary edema may occur early after envenomation and is thought to be from massive catecholamine release.
a granulomatous, nodular reaction that can occur in cases of ocular exposure to tarantula hairs.
Ophthalmia nodosa
Scorpion venom contains many toxins, but the toxins with the most serious medical effects can do what?
open neuronal sodium channels and cause prolonged and excessive depolarization
The most dangerous clinical manifestation of scorpion envenomation worldwide is
acute heart failure and pulmonary edema
For this reason, a blister beetle should be removed from the skin by
blowing or flicking
