Summary
Argyria is a dermatosis resulting from prolonged contact with or ingestion of silver salts. It is initially characterized by gray to gray-black or gray-blue staining of the gums, later progressing to diffuse skin involvement through silver deposition. It may be clinically apparent after a few months, but usually becomes obvious after many years and depends on the degree of exposure. The hyperpigmentation is most apparent in the sun-exposed areas of the skin. Great variability exists between individuals in the length of exposure and total dose needed to result in argyria. Argyria has become a rare dermatosis, mainly because of the withdrawal of silver-containing compounds as medicinals and a decrease in occupational exposure. The Blue Man, showed at the Barnum and Bailey Circus, had a classic case of argyria. Contact used to occur through occupational exposure (absorption of silver dust in metal manufacturing or photographic processing), medical procedures (silver sutures used in abdominal surgery, sites of acupuncture needles), or topical medicines (eye drops, wound dressings). Argyria also may be due to medications that are normally no longer used: silver dietary supplements for cancer, AIDS, diabetes mellitus, and herpetic infections. The human body normally contains approximately 1 mg of silver and signs of argyria may appear when levels reach 4-5 g, the lethal dose being 50-500 mg/kg. When argyria is suspected, the patient history should be carefully investigated, inquiring about possible occupational and environmental exposure, and use of dietary supplements. The diagnosis of argyria is established by skin biopsy. Histologic examination shows small, round, brown-black granules, single or in clusters, evident in the basement membrane zone surrounding the sweat glands. There is no satisfactory treatment. Chelation attempts to remove silver from the body have been unsuccessful. Sunscreens and opaque cosmetics may be helpful in preventing further pigmentary darkening and aid in masking obvious discoloration. *Author: Orphanet (April 2005)*.
