Human generalized argyria: a submicroscopic and X-ray spectroscopic study.

A 58-year-old man presented with a slate-gray discoloration of the skin. The patient had no medical complaint apart from the increasing cosmetic disability. He gave no drug history and denied professional exposure to chemical compounds. General medical examination was noncontributory; routine laboratory data were within the normal range. Light microscopy revealed the presence of numerous, small, pigmented particles at the dermal level. The submicroscopic investigation showed that the granules were deeply electron dense, had an irregular polycyclic contour, and varied in size between 100 and 600 nm. They were predominantly located in relation to the basal laminae of the epidermis and the cutaneous appendages, and in the dermal elastic fibers. In addition, the authors were able to document the presence of silver particles lying free in the cytoplasm of both epithelial cells of the secretory segment of eccrine sweat glands and mastcells, findings that have never been reported so far. X-ray spectroscopy documented that the electron-opaque particles contained silver, with some differences in the elemental composition of the granules, according to their location. These novel findings expand the knowledge of the various mechanisms of interaction of silver with the cellular and extracellular environment and allow some speculations about possible mechanisms of silver detoxification.