[Determination of serum IgE].

After recalling the properties of IgE antibodies responsible for allergic reactions, the author looks at the methods of assay by the techniques of radial immunodiffusion and radio-immunology. The total serum IgE of 13 subjects who had had an anaphylactic accident during anaesthesia, were assayed according to the latter technique. Elevated values were found in patient with an atopic background. The assay of IgE could be of value in the assessment of the allergic risk in anaesthesia.