In Reply.—
We appreciate the interest in our article and the opinions expressed by Roujeau et al. We admit that the incidence of delayed hypersensitivity to penicillin in the hospital population is much higher than that of actual allergic reactions to penicillin. Thus, it is unfortunate for us that instead of being induced by other much rarer drugs, our case of TEN was induced by ampicillin and our patient had delayed skin responses to it. This, however, does not exclude the possibility that the remarkable delayed hypersensitivity to ampicillin disclosed in our patient played a crucial role in the pathogenesis in her case of TEN. Most of all we wanted to emphasize the histologic finding of the positive patch test site to ampicillin that showed a prominent degenerative change in the epidermis