[Iatrogenic pseudotumor of the skin induced by polyvinyl pyrrolidone]

A 65-year-old woman developed a prominent tumor-like swelling of the skin in the face and shoulder area after having received parenteral applications of a drug containing polyvinylpyrrolidone (PVP) (Depot-Impletol) for many years. Upon first examination the alterations appeared to represent a tumor of the adipose tissue. Subsequently, however, they were shown to result from excessive storage of high-molecular fractions of PVP in the reticulohistiocytic system. Storage of these fractions of PVP, which cannot be eliminated with urine, was also found in the interstitial tissue of adjacent muscles and in local lymph nodes. The histological picture resembles a thesaurismosis. The present report also describes enzyme histochemical and electron-microscopic findings. The electron-microscopic results are similar to those described by other authors in the few ultrastructural reports of PVP storage. The ultrastructural alterations in the capillary endothelium suggest a transendothelial transport mechanism for the incorporated substance.