[Application of ELISA for the quantification of Androctonus australis hector venom in the envenomed serum of people and rats before and after immunotherapy].

Scorpion envenomation remains an important health problem in many countries in the world, especially in North Africa, Asia and America. In Algeria, the most dangerous species for humans are Androctonus australis hector (Aah) and Buthus occitanus tunetanus (Bot). These scorpions are responsible for the apparition of various symptoms in envenomed patients such as: pain, hypertention, hypotension, sudation and fever. An aggravation of clinical conditions of envenomed patients is characterized by a pulmonary cedema and myocardial damage. The evaluation of the severity of scorpion envenoming by immuno-enzymatic assay requires firstly, the preparation of a specific anti-horse F(ab')2 peroxydase conjugate not yet commercialized. The restatement of conditions of ELISA sandwich test allowed its utilization in determination of the venom concentration in envenomed patients and rats sera after envenoming by scorpion venom. Standardization of this test, its reproductibility, linearity and its detection limit were defined. The venom concentrations are directly deducted from standard curves prepared by the dilution of Androctonus australis hector in human serum collected from healthy donors and in non envenomed rats serum. The present study showed that ELISA test has a good linear response in a range of concentrations of venom antigen. Its detection limit was 0.5 ng/ml of Aah venom in serum. This specific test of scorpion envenoming aims in one side at establishing a correlation between venom levels and the clinical observations and at evaluating the severity of the envenoming before and after immunotherapy.