Derm Dx: Bluish nail discoloration

A 66-year-old male presents complaining of a bluish color on his fingernails. He is not significantly bothered by the appearance and is unsure of how long the color has been present, but wants to know the etiology of his nail changes.

The patient’s past medical history is significant for diabetes, hyperlipidemia and osteoarthritis. The patient also said he has had ...