Clinical Presentation and Outcomes Associated with Different Treatment Modalities for Pediatric Bark Scorpion Envenomation.

INTRODUCTION: Scorpion envenomation is potentially life-threatening and affects children in the Southwestern USA. An FDA-approved antivenom is available, but its high cost has led to use of off-label antivenom dosing or supportive care alone as alternatives to FDA-recommended dosing. This study sought to determine whether treatment approach influences outcomes in envenomated children.

METHODS: A retrospective cohort study of children with grade III or IV scorpion envenomation evaluated in Phoenix Children's Hospital ED between September 1, 2011, and March 31, 2014. Patients were grouped based on treatment: group 1, supportive care only; group 2, FDA-recommended dosing (3-vial initial dose); group 3, "off label" dosing (1-2 vial initial dose). Primary outcomes were ED length of stay and hospital admission. Secondary outcomes were mechanical ventilation and aspiration pneumonia.

RESULTS: One hundred fifty-six patients were included with 58 patients in group 1, 16 patients in group 2, and 82 patients in group 3. Group 1 was significantly older than the antivenom groups (p < 0.001), and group 2 was younger than group 3 (p = 0.024). Envenomation grade was also different, with group 1 having fewer grade IV then groups 2 and 3 (p < 0.001). Three percent of group 1, 56 % of group 2, and 28 % of group 3 had respiratory distress (p < 0.001). ED LOS was not significantly different between groups. Hospital admission occurred in 3.4 % group 1, no group 2, and 8.5 % group 3 patients. Two intubations and two aspirations occurred in group 3.

CONCLUSIONS: In this study, clinical presentation appeared to influence treatment. Groups that received antivenom had a higher envenomation grade than the group that received supportive care. The FDA-recommended dosing group was younger and had more respiratory distress than those treated with initial doses of 1-2 vials. Outcomes were not significantly different between groups. Prospective studies may identify the ideal population for each treatment approach.