Often there is a history of a laceration or minor trauma to the skin or mucous membrane several days to a few weeks before presentation, but in most cases there is no apparent cause. The head, neck, and extremities are most commonly involved, especially the lips, oral mucosa, and fingers. An unsightly lesion forms, beginning as an extremely friable red or yellow papule or polyp, bleeding with every slight trauma. Objective findings usually include a crusted, sometimes purulent-appearing collection of erythematous, well-demarcated, red granulation tissue arising from a moist, sometimes hemorrhagic, skin ulceration, often with a collarette of scale at the base. There are usually no signs of a deep tissue infection (Fig. 178.1).