Localized cutaneous argyria: two case reports and clinicopathologic review.

We report 2 cases of patients who presented with blue macules clinically suspicious for blue nevi. One patient had no documented history of trauma or silver exposure, and the other reported exposure to silver over 30 years ago. Microscopic examination revealed a dermal population of brown-black globules predominantly adhering to collagen fibers. In both cases, no melanocytic proliferation was identified by immunohistochemistry. Analysis of the skin biopsies with scanning electron microscopy and energy dispersive x-ray spectroscopy demonstrated the presence of silver and selenium. These findings were diagnostic of localized cutaneous argyria. Our case reports highlight the importance of including localized cutaneous argyria in the differential diagnosis of pigmented lesions.