Localized argyria secondary to acupuncture mimicking blue nevus.

The typical clinical manifestation of localized cutaneous argyria is a blue-grayish asymptomatic macule, which may be caused by occupational exposure, topical treatment, dental amalgams and alternative medicine therapies. The lesions often are clinically indistinguishable from blue nevi and metastatic melanoma. The authors present a case of localized cutaneous argyria secondary to an acupuncture needle, emphasizing the importance of keeping this entity in mind in the differential diagnosis of blue-grayish pigmented lesion in a body area that could have been treated with acupuncture.