Chromonychia in an Asymptomatic Vitamin Consumer

A 74-year-old woman with no significant past medical history presented with nail discoloration for 5 years. The discoloration began on her right thumb and progressed to involve all 10 fingernails, sparing the toenails. The patient stated she has been using a variety of ‘natural supplements’ for decades, but denied taking any medications. Examination of the nails revealed longitudinal ridging and nonblanching, bluish-gray pigmentation of the proximal nail bed following the shape of the lunula. This was more evident on the thumbs ( fig. 1 ). Examination of the skin, oral and ocular mucosa was negative for dyspigmentation. No organomegaly, neuropsychiatric dysfunction or ocular rings were identified. What is your diagnosis? Received: September 25, 2015 Accepted: September 30, 2015 Published online: November 6, 2015