[Lichenoid pityriasis. Immunologic study of 10 children]

Ten children clinically and histologically diagnosed as having pityriasis lichenoides (PL), have been studied by direct immunofluorescence (DIF). Circulating immune complexes (CI) have also been studied in four children. Granular deposits of IgM, located in the walls of the dermal vessels have been observed in two cases, but they have never been found at the dermo-epidermal junction. Granular deposits of C3 have been observed in three children, both in the walls of the dermal vessels and at the dermo-epidermal junction. The search for immune complexes gave negative results in all cases. The hypothesis of some authors that PL is an immune complex disease cannot be confirmed by our findings.