ABSTRACT
It is a vascular alteration due to trauma or following surgical procedures. Clinically, it appears as a subungual or periungual purple nodule or even as erythronychia. Some benign nail tumors (onychopapilloma, hemangioma, and glomus tumor), as well as malignant ones (Bowen and squamous cell carcinoma), are considered differential diagnoses. Dermoscopy helps to localize and delimitate the lesion. Histopathology confirms the diagnosis ( Figure 18.1 ).
