title: A randomized blinded clinical trial of two antivenoms, prepared by caprylic acid or ammonium sulphate fractionation of IgG, in Bothrops and Porthidium snake bites in Colombia: correlation between safety and biochemical characteristics of antivenoms.
abstract: A randomized blinded clinical trial was performed in 53 patients bitten by Bothrops sp. and Porthidium sp. in Antioquia and Chocó, Colombia, in order to compare the efficacy and safety of two antivenoms made of whole IgG obtained by either ammonium sulphate (monovalent anti-B. atrox) or caprylic acid (polyvalent) fractionation. Additionally, antivenoms were compared by electrophoretic and chromatographic analyses and anticomplementary activity in vitro. With a protocol of 2, 4 and 6 antivenom vials for the treatment of mild, moderate and severe envenomings, respectively, both antivenoms were equally efficient to neutralize the most relevant signs of envenoming and to clear serum venom levels in patients from the first hour and later on. Three patients with severe envenoming and initially treated with less than six vials on admission had persistent or recurrent venom antigenemia within 12-48 h. Monovalent antivenom fractionated by ammonium sulphate precipitation had higher amounts of protein aggregates and nonimmunoglobulin proteins than polyvalent antivenom fractionated by caprylic acid precipitation. Both antivenoms presented anticomplementary activity in vitro, being higher in the monovalent product. In agreement, monovalent antivenom induced a significantly higher incidence of early antivenom reactions (52%) than polyvalent antivenom (25%).
authors.affiliation: Centro de Investigaciones Médicas, Departamento de Pediatría, Facultad de Medicina, Universidad de Antioquia, Medellín, Colombia.
authors.forename: R
authors.initials: R
authors.lastname: Otero
authors.forename: J M
authors.initials: JM
authors.lastname: Gutiérrez
authors.forename: G
authors.initials: G
authors.lastname: Rojas
authors.forename: V
authors.initials: V
authors.lastname: Núñez
authors.forename: A
authors.initials: A
authors.lastname: Díaz
authors.forename: E
authors.initials: E
authors.lastname: Miranda
authors.forename: A F
authors.initials: AF
authors.lastname: Uribe
authors.forename: J F
authors.initials: JF
authors.lastname: Silva
authors.forename: J G
authors.initials: JG
authors.lastname: Ospina
authors.forename: Y
authors.initials: Y
authors.lastname: Medina
authors.forename: M F
authors.initials: MF
authors.lastname: Toro
authors.forename: M E
authors.initials: ME
authors.lastname: García
authors.forename: G
authors.initials: G
authors.lastname: León
authors.forename: M
authors.initials: M
authors.lastname: García
authors.forename: S
authors.initials: S
authors.lastname: Lizano
authors.forename: J
authors.initials: J
authors.lastname: De La Torre
authors.forename: J
authors.initials: J
authors.lastname: Márquez
authors.forename: Y
authors.initials: Y
authors.lastname: Mena
authors.forename: N
authors.initials: N
authors.lastname: González
authors.forename: L C
authors.initials: LC
authors.lastname: Arenas
authors.forename: A
authors.initials: A
authors.lastname: Puzón
authors.forename: N
authors.initials: N
authors.lastname: Blanco
authors.forename: A
authors.initials: A
authors.lastname: Sierra
authors.forename: M E
authors.initials: ME
authors.lastname: Espinal
authors.forename: R
authors.initials: R
authors.lastname: Lozano
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000645:Ammonium Sulfate / Q000737:chemistry; D000818:Animals; D000997:Antivenins / Q000009:adverse effects / Q000302:isolation & purification / Q000627:therapeutic use*; D017837:Bothrops; D002210:Caprylates / Q000737:chemistry; D005591:Chemical Fractionation / Q000379:methods; D002648:Child; D002675:Child, Preschool; D003105:Colombia; D003435:Crotalid Venoms / Q000276:immunology*; D004311:Double-Blind Method; D006736:Horses; D006801:Humans; D007074:Immunoglobulin G / Q000009:adverse effects / Q000302:isolation & purification / Q000627:therapeutic use*; D007223:Infant; D008875:Middle Aged; D012449:Safety; D012909:Snake Bites / Q000628:therapy*; D016896:Treatment Outcome
chemical_list: D000997:Antivenins; D002210:Caprylates; D003435:Crotalid Venoms; D007074:Immunoglobulin G; C031492:octanoic acid; D000645:Ammonium Sulfate