CLINICAL INDICATORS OF ENVENOMING AND SERUM LEVELS OF VENOM ANTIGENS IN PATIENTS BITTEN BY BOTHROPS LANCEOLATUS IN MARTINIQUE

An enzyme-linked immunosorbent assay was developed to measure venom an tigen levels in the serum of 40 patients bitten by Bothrops lanceolatu s. The grading system used for the severity of envenomation (grades 1 to 4, minor to major) was predominantly based on the presence of local signs. Serum venom levels increased with the grade of severity (P<0.0 01, by Spearman's rank correlation test); they were 6+/-6 ng/mL (mean/-SD) in clinically non-envenomed patients (grade 1, n=3), 7.6+/-11.7 (n=17), 44.3+/-41.8 (n=17), and 80.3+/-34.1 ng/mL (n=3) in patients di agnosed as grade 2, 3 and 4 respectively. However, venom antigens coul d not be detected in the serum of 54% of patients who showed clinical signs of envenomation. Most patients diagnosed as grade 2, 3 or 4 were given 20, 40 and 60 mt of a monospecific F(ab')2 antivenom, respectiv ely. Venom concentrations greater than or equal to 15 ng/mL were obser ved in all patients with progressive aggravation of swelling despite t he use of early antivenom therapy. No venom was detectable in blood sa mples taken after completion of serotherapy. All patients recovered. T hese results confirm the efficacy of both the clinical severity scorin g system used and the therapeutic regimen.