[Immunofluorescence and immunoperoxidase: a comparison for sensitivity in cutaneous immunopathology (author's transl)].

A comparative study of the sensitivities of the immunofluorescence (IF) and immunoperoxydase (IPo) techniques was undertaken. The material used was biopsies of various skin lesions and especially pemphigus, bullous pemphigoid, lupus erythematosus and dermatitis herpetiformis. Direct and indirect methods were performed for the detection of fixed immunoglobulins and complement deposits. With large deposits, immunoperoxydase and immunofluorescence show an equal sensibility and the labeling obtained with IPo is never more intensive than the labeling obtained with IF. In contrast, with small deposits, IPo was less sensitive than IF and appears negative in the majority of the cases and especially in dermatitis herpetiformis. These results are confirmed in using increasing dilutions of conjugates and can be explained by the difficulty in doing the observation of small positive deposits with IPo.