Safety and efficacy of Crotalidae Polyvalent Immune Fab in pediatric crotaline envenomations.
BACKGROUND
Since it was approved by the Food and Drug Administration in October 2000, Crotalidae Polyvalent Immune Fab (CroFab) has largely replaced previously used crotaline antivenom. CroFab is more specifically tailored for crotalids of North America and is less allergenic than whole immunoglobulin antivenoms. However, premarketing and postmarketing studies have excluded children.


OBJECTIVE
To describe the safety and efficacy of CroFab in pediatric crotaline envenomations.


METHODS
Using admission and billing records, the authors identified all children 13 years of age and younger treated with CroFab at a pediatric hospital between October 2000 and September 2005. Charts were reviewed by two trained, blinded extractors. Data regarding age, signs of envenomation, laboratory values, total antivenom vials used, total vials used to gain control, transfused blood products, signs of acute allergy to antivenom, and any surgical procedures were abstracted. Data were analyzed using descriptive statistics.


RESULTS
Twenty-four patients were identified, and their mean age was 7.3 (range, 1.9-13) years. At presentation, all had swelling, 14 (58%) had a prothrombin time >13 seconds, two (8.3%) had a fibrinogen level <150 mg/dL, and three (12.5%) had platelet counts <150,000/mL. The mean number of total antivenom vials used was 12.3 (range, 4-24). Five patients had resolution of swelling, but platelet counts continued to fall despite antivenom treatment. No patient required blood products, debridement of skin, or fasciotomy. There was only one (4.2%) possible acute allergy to CroFab, and there were no deaths.


CONCLUSIONS
In this pediatric series, CroFab appears safe and effective, despite occasional resistant thrombocytopenia.
Pizon
Anthony F
AF
Division of Medical Toxicology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA. pizonaf@upmc.edu
Riley
Bradley D
BD
LoVecchio
Frank
F
Gill
Ruqayya
R
D000293:Adolescent; D000997:Antivenins / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006776:Hospitals, Pediatric; D006801:Humans; D007140:Immunoglobulin Fab Fragments; D007128:Immunoglobulin Fragments / Q000627:therapeutic use*; D007223:Infant; D008297:Male; D012189:Retrospective Studies; D012909:Snake Bites / Q000628:therapy*; D016896:Treatment Outcome
D000997:Antivenins; C431183:Crotalidae Polyvalent immune Fab; D007140:Immunoglobulin Fab Fragments; D007128:Immunoglobulin Fragments