CASE REPORT
A 38-year-old Japanese male was referred to our department with a 5-year history of a black macule without itching or pain on the right 5th finger. The patient did not recall any traumatic events before the onset. The patient had not engaged in any tasks or sports associated with hand activities. The patient had an unremarkable medical history and had received no medication, including anticoagulants and antiplatelet agents. In a physical examination, a black macule measuring 2 mm in diameter was noted on the ulnar side of the right 5th finger (Figure 1a). Dermoscopy showed a well-demarcated homogeneous reddish black area involving the sulci cutis and crista cutis (Figure 1b). There was a keratinized recess in the center. Histopathology revealed hemorrhage within the corneal layer and dilated capillary venules containing erythrocytes just beneath the epidermis with the extravasation of erythrocytes around the venules (Figures 1c and 1d). Therefore, the patient was diagnosed with solitary angiokeratoma accompanied by intracorneal hemorrhage.