Localized cutaneous argyria: Review of a rare clinical mimicker of melanocytic lesions.

Localized cutaneous argyria is a rare cutaneous disorder that has been associated with occupational exposure, dental procedures, topical agents, acupuncture, earrings, and nasal piercings. In this paper, we review the current literature on localized cutaneous argyria, highlight its clinical and histologic diagnostic features, and then discuss the clinical and histological differential diagnoses for blue-gray skin and black dermal pigment, respectively. We also discuss the utility of ancillary techniques, such as deeper histologic levels, special stains, darkfield microscopy, and advanced micro-analytical techniques in helping diagnose localized cutaneous argyria. Furthermore, we emphasize that a thorough clinical history and astute clinico-pathologic correlation can be the most important diagnostic techniques in correctly diagnosing this rare disorder. Our review aims serve as a reminder to clinicians and pathologists of the importance of including localized cutaneous argyria in the clinical and histological differential diagnosis of pigmented lesions.