[Andrews' pustular bacterids of hands and feet; Sachs' acrodermatitis pustulosa perstans. Histological study (author's transl)].

Pustulosis palmaris et plantaris chronica et recidivans (pustular bacterid of Andrews) is not an exceptional disease. Its characteristic histological structure is to be considered as a major element of the diagnosis. The fully developed pustule is an oval cavity with transverse long axis, entirely situated within a loca-ly hyperplastic epidermis. Its formation goes through several stages. The first one is spongiosis appearing in the epidermis above the top of a dermal papilla. This gives rise to a vesicle filled with fluid and mononuclear leucocytes. In the next stage, the roof consisting of the malpighian layers is disrupted, and the vesicular fluid comes into contact with the horny layer. There is massive invasion of the cavity by polymorphonuclear leucocytes which penetrate into the intercellular spaces of the vesicle wall, where pictures of spongiform pustules are seen. The initial vesicle, and the late, secundary appearance of the spongiform aspects demonstrate that the mechanism of formation of the lesion of pustulosis palmaris et plantaris chronica et recidivans is different from the one of psoriasis pustulosa palmo-plantaris and that, consequently, these are two different diseases.