Somerset outlined basic features that are helpful in distinguishing the various lesions caused by insects and other nuisances in the natural world.
Immediate Response |
Later |
Other |
Agent |
may recall crushing a small biting insect |
swollen skin with linear weals and a central yellow line, |
may develop vesicles |
Paederus blister beetle |
may recall crushing a small biting insect |
large skin blisters |
|
other types of blister beetles |
usually not noted |
localized area of edema with central erythema |
|
mosquito, fly or midge |
painful bite |
localized area of edema |
|
ant |
very painful |
edema |
insect seen |
bee, wasp, hornet |
very painful |
often significant |
|
spider |
very painful |
often significant |
scorpion seen, desert |
scorpion |
usually not noted |
small red papules |
pruritic with scratching |
bed bug, fleas |
usually not noted |
urticaria, red weals |
hairs found on skin, caterpillar seen |
caterpillar |
painless |
puncture marks bleed freely |
leech attached, in jungle and/or water |
leech |
sudden pain with linear weals |
|
bathing at sea |
jelly fish |
skin red, hot and raised, may be painful |
spreading |
Gram stain and culture |
erysipelas |
where:
• A central yellow line in a linear weal is good evidence for Paederus.
• Blister beetles other than Paederus include the Meloidae (Cantharidae), which has several genera – Epicauta, Lytta (Spanish fly), Mylabris (Chinese blister beetle).
• Horse flies can cause a painful bite.
Specialty: Toxicology, Emergency Medicine, Critical Care