Pigmented nail streaks may indicate Laugier-Hunziker syndrome.

Laugier-Hunziker syndrome is a rare, benign pigmentation disorder previously described only once in the United States. The syndrome is acquired in early or mid-adult life and is characterized by multiple longitudinal hyperpigmented bands on the nails and pigmented macules of the lips and buccal mucosa. Peutz-Jeghers syndrome and Addison's disease can present with pigment abnormalities similar to those characteristic of Laugier-Hunziker syndrome.