Pygmy rattlesnake envenomation treated with Crotalidae Polyvalent Immune Fab Antivenom

Documented envenomations by the pygmy rattlesnake (Sistrurus miliarius barbouri) are rare. While there have been no documented fatalities, several older case reports describe significant morbidity. We describe the first known case of pygmy rattlesnake envenomation that was treated with Crotalidae Polyvalent Immune Fab Antivenom (CroFab®).

Case: A 28-year-old man with no significant past medical history presented after being envenomated on the right hand by his friend's pet pygmy rattlesnake. He developed swelling and pain in his hand and forearm. He responded well to a ten vial loading dose and a 18 h maintenance protocol of CroFab and was discharged the following day without developing any hematological or electrolyte derangements.

Conclusion: This is the first documented use of CroFab for S. m. barbouri envenomation. The outcome of this case suggests that CroFab is a safe treatment modality in this setting.