Author: Vanessa Ngan, Staff Writer, 2003.
An angiokeratoma is a small red to purple papule. It may have a rough scaly surface. It is composed of surface blood vessels (dilated capillaries). Often unnoticed, an angiokeratoma may become crusty and bleed if accidentally scratched or damaged, or a harmless clot may form in the lesion (thrombosis), changing the colour to dark purple or black overnight.
There are several types of angiokeratomas:
Apart from Fabry disease, which is caused by a genetic defect, the cause of other angiokeratomas is unknown.
Angiokeratomas are harmless surface vascular lesions that can usually be left alone. As the black spots sometimes resemble melanoma, a skin biopsy may be performed to rule out malignancy and allay any fears.
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