[Polyvinylpyrrolidone dermatoses. Clinical aspects and ultrastructural morphology]

High-molecular polyvinylpyrrolidone (PVP) is used in order to induce a depot of subcutaneously or intramuscularly applied drugs. Deposits of PVP in skin plaques persisting for years and distant from the injection site have been demonstrated by the use of a modified fixation and embedding method for electron microscopy. The storage of PVP did not only occur in macrophages but also in other dermal cells whose pinocytotic activity seems to have been underestimated so far. PVP was found in mucinous and serous cells of sweat glands, in myoepithelial cells, endothelial cells, mast cells, and in the perineurium as well as in Schwann cells.