What is the hallmark of pit viper envenomation?

• A. 1 or 2 fang marks with pain, erythema, ecchymosis, and edema
• B. Profuse sweating with no local bite marks
• C. No swelling or redness at the bite site
• D. Painful lymphadenopathy without skin changes

Answer: (A)

Pit viper envenomation is marked by local tissue injury at the bite site. The hallmark is one or two fang marks with immediate painful, inflamed tissue showing redness, bruising, and swelling as venom damages small vessels and surrounding tissues. This local reaction is the most characteristic sign and often appears early, though systemic effects can follow in some cases. The other presentations—profuse sweating without local bite marks, no swelling or redness at the bite site, or painful lymphadenopathy without skin changes—do not reflect the typical localized venom-induced injury from a pit viper bite.