What type of skin lesion is described as solitary, faintly pigmented, and occurring at sites of previous trauma?

The description of a skin lesion as solitary, faintly pigmented, and occurring at sites of previous trauma aligns well with a dermatofibroma. This type of lesion is typically a benign fibrous tumor arising from the dermis and is commonly found on the lower extremities. Dermatofibromas are known for their characteristic appearance, which can range in color but often presents as brown or slightly pigmented, giving them a faintly pigmented appearance.

The association with previous trauma is particularly noteworthy since dermatofibromas often develop in response to skin injuries such as insect bites, cuts, or other forms of physical trauma. The solitary nature of these lesions also fits the description, as they are generally found as single entities rather than multiple lesions.

Other conditions mentioned may have attributes that overlap with this description, but they do not align in the same way. For instance, a Spitz nevus is usually more variably pigmented and can present as multiple lesions, while atypical nevus syndrome tends to involve numerous atypical moles that have a greater risk of melanoma. Basal cell carcinoma often appears as a nodular or ulcerated lesion, which does not match the characteristics of being faintly pigmented or solitary in the same context