[Snake bite by European vipers. A multicenter study of tolerance to Viperfav, a new intravenous antivenom].
OBJECTIVE
To evaluate the tolerance and the effectiveness of i.v. Viperfav, a new antivenom containing F(ab')2 fragments of equine antibodies, for the treatment of European viper envenomed patients.


METHODS
Open, multicentre field trial, associated with a cohort study.


METHODS
The study included 46 patients of either gender, nine aged less then 10 years, eight between 10 and 15 years, and 28 adults, who sustained a moderate or severe viper envenomation (Grade 2 or 3).


METHODS
At the inclusion, a single infusion of Viperfav was given. Depending on the clinical course, up to four additional infusions were to have been administered at 4-hour intervals. To evaluate tolerance, all symptoms were recorded. There were three effectiveness evaluation criterion (duration of hospitalisation, course of the severity grade, recovery (sequelae)) and one subjective criteria (value of the antivenom as ascertained by investigators).


RESULTS
In the 46 included patients, 79 infusions were administrated. Concerning tolerance, six mild symptoms were associated to the antivenom infusions. No severe reaction occurred. The mean duration of hospitalisation was 4 days 19 hours +/- 13 hours. A severity grade decrease by at least one point was observed in 35 patients, and all were discharged without sequelae. For the investigators the antivenom was inefficient in only two patients (grade 3 with tissue lesions).


CONCLUSIONS
In comparison with literature data (5 to 10% of severe reactions attributable to the antivenom), the tolerance of Viperfav can be considered as satisfactory. As all criteria were in favour of a positive benefit to risk ratio, the authors recommend the use of Viperfav i.v. for the grade 2 and 3 envenomations instead of the current less purified antivenom, which can only be administered by the intramuscular route.
de Haro
L
L
Centre anti-poisons, hôpital Salvator, Marseille, France.
Lang
J
J
Bedry
R
R
Guelon
D
D
Harry
P
P
Marchal-Mazet
F
F
Jouglard
J
J
D000293:Adolescent; D000328:Adult; D000818:Animals; D000997:Antivenins / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D002648:Child; D015331:Cohort Studies; D005260:Female; D006736:Horses; D006801:Humans; D007140:Immunoglobulin Fab Fragments / Q000627:therapeutic use; D007275:Injections, Intravenous; D008297:Male; D012909:Snake Bites / Q000628:therapy*; D014757:Viper Venoms / Q000506:poisoning*; D017819:Viperidae
D000997:Antivenins; D007140:Immunoglobulin Fab Fragments; D014757:Viper Venoms