Evaluation of Scorpion Envenomation by Tityus trivittatus in Adults: An Analysis of Variables Related to Severity of Clinical Presentation

Introduction: In Argentina, the scorpion species Tityus trivittatus has been the species most commonly associated with serious injury and death. Methods: We performed a retrospective study of cases of T trivittatus envenomation that presented to the emergency department at an infectious disease hospital in Cordoba, Argentina, between December 2014 and February 2015. All cases were taxonomically confirmed using criteria established in the Argentine Ministry of Health national guidelines. The primary outcome was classification of clinical presentation (mild/moderate/severe). Classification of clinical presentation was performed in a post hoc fashion using the national guidelines and compared to the classification of clinical presentation given to patients at the time of diagnosis in the emergency department. Results: We included 450 individuals with T trivittatus envenomation. The median age of was 36 y (interquartile range 25–52), and 57% were female. In the emergency department, only 5 patients (<1%) were diagnosed as moderate cases and received antivenom; all other cases were diagnosed as mild. Conversely, in our post hoc classification of clinical presentations, 280 patients had mild presentations, 170 had moderate presentations, and no patients had severe presentations. In our cohort, there were no deaths, no inpatient hospital admissions, and no requirements for continuous cardiac monitoring. We found that age >50 y, (odds ratio [OR] 2.5, P<0.001), time from sting to presentation >120 min (OR 2.6, P=0.02), and pre-existing hypertension (OR=3.9, P<0.001) were all independently associated with worse post hoc classification severity. Conclusions: Our study exposed factors associated with moderate presentations of scorpion envenomation and proposes the option of conservative treatment for affected adults.