Unwitnessed rattlesnake envenomation: a difficult diagnosis.

Crotaline snake species are endemic to the USA and are responsible for most cases of snakebite envenomation nationally. There is limited data reporting the incidence of unwitnessed snakebite envenomation in the USA; however, this is likely not an uncommon occurrence. In these cases, diagnosis is challenging as clinical findings can be non-specific and laboratory testing may be of limited use. Herein, we present a case of an unwitnessed crotaline snakebite envenomation that initially mimicked bacterial cellulitis. This case highlights the need for clinicians to maintain a high level of suspicion for snakebite envenomation in cases without a witnessed snakebite.