The anatomical classifies according to the structure responsible for the white color: the nail plate in true leukonychia, the nail bed in apparent leukonychia, and the surface only in pseudoleukonychia. Mees’ and Muehrcke’s lines are examples of transversal leukonychia, while Terry’s and Lindsay’s nails are examples of total and partial leukonychia. The morphological classifies the nail according to the distribution of the white lines: total, partial, transversal, and longitudinal leukonychia. In the past, two classifications for leukonychia have been presented. Therefore, a reliable assessment of the patient with leukonychia is essential. In particular, white discoloration (leukonychia) has a high prevalence with a wide array of potential relevant causes, from simple manicure habits to life-threatening liver or kidney failure. Changes in nail color can provide important clues of underlying systemic and skin disease.
