Skin Discoloration and Damage could be one of the following and should be looked into thoroughly.
Postinflammatory hyperpigmentation is a common consequence of an injury or inflammation to dark skin (Fitzpatrick types IV to VI), resulting in lesions that can persist for months or years. This can be psychologically devastating to some patients. Postinflammatory hyperpigmentation may also occur after laser therapy for other pigmented skin lesions, and may be transient or long lasting.
Postinflammatory hyperpigmentation presents as irregular, darkly pigmented small, flat lesions and patches at sites of previous injury or inflammation. Treatment is often difficult, requiring prolonged courses of therapy and excellent patient compliance.
Melasma is a progressive, smooth, , macular, nonscaling hypermelanosis of sun-exposed areas of the skin, primarily on the face and dorsal forearms. It is usually associated with pregnancy, oral contraceptives, or anticonvulsants, or it may be idiopathic. Melasma affects women nine times more often than men, and it is more prominent in patients with skin types IV to VI (e.g., Asian, Middle Eastern, South American). It is usually asymptomatic, but it is often cosmetically distressing to the patient. Melasma typically presents in one of three patterns of distribution: centrofacial (63 percent), malar (21 percent), and mandibular (16 percent).
Solar lentigines (i.e., liver spots) are macular, 1- to 3-cm, hyperpigmented, well-circumscribed lesions on sun-exposed surfaces of the skin. They vary in color from light yellow to dark brown, and they often have a variegated appearance. The face, hands, forearms, chest, back and shins are the most common locations, erupting after acute or chronic UV exposure. White or Asian persons are most likely to develop solar lentigines, especially those with skin types I to III and a tendency to freckle.
Resources: American Family Physician