Argyria

Argyria is a rare acquired condition characterized by a slate-blue to bluish-gray discoloration of the skin and mucous membranes caused by the deposition of silver in body tissues after chronic exposure to silver compounds or ingestion of silver-containing products.

Causes include occupational exposure to silver dust or compounds in industries such as photography, mining, electronics, and silverware production; medical or consumer use of colloidal silver or silver nitrate solutions; and prolonged use of dietary supplements or other products containing silver. In some cases, cosmetic or alternative medicine sources have contributed to exposure.

Pathophysiology involves the accumulation of silver particles in the dermis and other tissues. Light exposure can promote chemical reactions that form silver sulfide or silver selenide, contributing to the characteristic blue-gray coloration. The resulting pigmentation is typically permanent and does not necessarily indicate ongoing systemic toxicity, though high silver burdens can be associated with other health effects depending on exposure.

Clinical features commonly begin with diffuse pigmentation that tends to involve sun-exposed areas such as the face, neck, and hands, and may also affect nails and mucous membranes. Localized argyria can occur at sites of direct exposure. A related condition, argyrosis, describes silver deposition in the eye and is considered separate from cutaneous argyria.

Diagnosis is based on history of silver exposure and characteristic appearance. Laboratory tests may show elevated silver levels in some individuals but do not reliably correlate with skin pigmentation; skin biopsy with specialized staining can reveal dermal silver deposits.

Treatment and prognosis: there is no proven medical therapy to reverse argyria. Stopping further silver exposure is essential. Cosmetic improvement has been reported with laser therapy in some localized cases, but generalized argyria is often resistant. Prevention through avoidance of silver-containing products is advised.