Medical Concern for Colloidal Silver Supplementation: Argyria of the Nail and Face

Dear Editor:

A 75-year-old female presented to our hospital concerned about gray discoloration of the skin. The patient began to notice changes in her complexion approximately a year prior to presentation. She had been ingested colloidal silver for four years to treat her diabetes. The patient's medical history included type II diabetes, hypertension and early gastric cancer. Skin examination revealed gray discoloration involving the proximal half of the finger nails and patches on the face (Fig. 1). Skin biopsy of her face was performed. The biopsy specimen revealed a few fine brown-to-black granular deposits concentrated around eccrine glands and hair follicles (Fig. 2). The diagnosis of argyria in our patient is suspected clinically and confirmed by skin biopsy conducted on her face. We recommended the patient to limit the intake of colloidal silver and avoid sunlight. Argyria results from prolonged ingestion of silver salts. The deposition of silver in the skin produces a slate-gray pigmentation. The discoloration of the skin is typically apparent in sun-exposed areas. Also, the silver deposition mechanism and pathogenesis of argyria is not fully understood. In addition, the discoloration may be caused by the reduction of elemental silver by sunlight and melanocyte stimulation¹. By literatures, histopathological examination of argyria reveals black granules in the basement membrane zone surrounded by sweat glands and connective tissue sheaths around pilosebaceous structures². Silver deposition and discoloration of the skin in argyria is a rare condition, especially in fingernails. There is no effective treatment except for the discontinuation of silver salt. The differential diagnosis for argyria includes Wilson disease, ochronosis, hydrayrosis, and antimalarial drugs³. Colloidal silver is widely marketed as a folk remedy for diabetes, acquired immune deficiency syndrome, cancers and infections. Most reported cases of argyria had occurred following ingestion of 4~5 g⁴. People believe colloidal silver based products as cure-alls despite its unsubstantiated claims of effectiveness against major illnesses. With an increasing number of reports of problems associated with silver ingestion, dermatologists should warn patients in regards to the use of colloidal silver for medicinal purposes.

Fig. 1.

Clinical findings. (A) Slate-blue pigmentatioin of the lunula of the finger nails. (B) Slate-gray colored patches on face.

Fig. 2.

Histopathological findings. (A) Fine brown-to-black granular deposition around eccrine glands (arrows) (H&E, ×400). (B) Around hair follicles (arrows) (H&E, ×400).