MICHAEL E.MINGMD, MSCE
A 34-year-old white woman presented with a 10-year history of pigmentation of the second right fingernail. A blue-gray, well-limited, semicircular spot was seen in the middle of the lunula (Figure 1). Superficial linear erosion of the nail plate extended from the distal part of the tumor process to the distal nail plate. Hutchinson sign was absent. Dermoscopic examination revealed a homogeneous blue discoloration on the distal matrix, with a few linear hemorrhages on the nail plate (Figure 2). There was no clear history of local trauma. Only 1 finger was affected. An x-ray film of the phalanx showed no abnormalities.
Dalle S, Ronger-Savle S, Cicale L, Balme B, Thomas L. A Blue-Gray Subungual Discoloration—Quiz Case. Arch Dermatol. 2007;143(7):937-942. doi:10.1001/archderm.143.7.937-d