Which insect bite causes immediate pain and paresthesia with a positive tap test, and what is the treatment?

Which insect bite causes immediate pain and paresthesia with a positive tap test, and what is the treatment?

• A. Centipede bite; topical antibiotics
• B. Bees sting; oral antihistamines
• C. Scorpion sting; antivenom is available but symptoms may resolve in 24-48 hours without antivenom
• D. Spider bite; ice and elevation

Answer: (D)

The key idea is recognizing venom effects that cause immediate local pain and sensory changes from an insect bite, with a sign that points to nerve irritation at the bite site. When a bite produces sharp, sudden pain plus paresthesias and tapping around the area reproduces that sensation, it suggests local neurotoxic irritation rather than simple inflammation or infection. Among common bites, a spider bite is most likely to produce that rapid pain and sensory disturbance, and the appropriate initial management is simple supportive care: cold packs (ice) to reduce pain and swelling and elevation of the affected limb to minimize edema. Most spider bites are self-limited and do not require antibiotics or specific antivenom, unless there are signs of severe systemic envenomation or atypical progression. The other options involve different patterns: centipede bites are known for acute, intense pain but not the same characteristic sensory tapping sign; bee stings are typically treated by removing the stinger and managing swelling and itching with antihistamines; scorpion stings can cause significant pain and autonomic symptoms and sometimes require antivenom, but many cases resolve without it within 24–48 hours. The takeaway is that the described clinical pattern aligns best with a spider bite managed with ice and elevation.

The key idea is recognizing venom effects that cause immediate local pain and sensory changes from an insect bite, with a sign that points to nerve irritation at the bite site. When a bite produces sharp, sudden pain plus paresthesias and tapping around the area reproduces that sensation, it suggests local neurotoxic irritation rather than simple inflammation or infection.

Among common bites, a spider bite is most likely to produce that rapid pain and sensory disturbance, and the appropriate initial management is simple supportive care: cold packs (ice) to reduce pain and swelling and elevation of the affected limb to minimize edema. Most spider bites are self-limited and do not require antibiotics or specific antivenom, unless there are signs of severe systemic envenomation or atypical progression.

The other options involve different patterns: centipede bites are known for acute, intense pain but not the same characteristic sensory tapping sign; bee stings are typically treated by removing the stinger and managing swelling and itching with antihistamines; scorpion stings can cause significant pain and autonomic symptoms and sometimes require antivenom, but many cases resolve without it within 24–48 hours. The takeaway is that the described clinical pattern aligns best with a spider bite managed with ice and elevation.