acanthosis nigricans symptoms
This form of acanthosis nigricans is more likely to involve mucous membranes (25-50% of cases) Malignant acanthosis nigricans that may either precede (18%), accompany (60%), or follow (22%) the onset of an internal cancer. If you experience any of these symptoms, do not assume it is due to acanthosis nigricans. These symptoms may be caused by other health conditions. 1  Velvety-looking, dark areas on: 2  Back of the neck. 3  Armpits. 4  Groin. 5  Elbow. 6  Knees. 7  Knuckles. The most common locations for acanthosis nigricans include: Less commonly, acanthosis nigricans can affect these areas: Very rarely, acanthosis nigricans can be found in these locations: The lesions of acanthosis nigricans appear as velvety thickenings, and they can range in color from gray to brown to black. Acanthosis nigricans is conventionally divided into benign and malignant forms, although may be divided into syndromes according to cause: 1  Benign This may include obesity-related, hereditary, and endocrine forms of acanthosis nigricans. It delineates acanthosis nigricans syndromes according to their associated syndromes, including benign and malignant forms, forms associated with obesity and drugs, acral acanthosis nigricans, unilateral acanthosis nigricans, and mixed and syndromic forms. Back to Top Symptoms. Acanthosis nigricans usually appears slowly and doesn't cause any symptoms other than skin changes. Eventually, dark, velvety skin with very visible markings and creases appears in the armpits, groin and neck folds, and over the joints of the fingers and toes. Acanthosis nigricans is a brown to black, poorly defined, velvety hyperpigmentation of the skin. It is usually found in body folds, such as the posterior and lateral folds of the neck, the armpits, groin, navel, forehead, and other areas. Obesity can lead to acanthosis nigricans, as can some endocrine disorders. It is often found in people with obesity-related insulin resistance. Some medicines, particularly hormones such as human growth hormone or birth control pills, can also cause acanthosis nigricans. Back to Top Exams and Tests. Your health care provider can usually diagnose acanthosis nigricans by looking at your skin. A skin biopsy may be needed in unusual cases. If there is no clear cause of acanthosis nigricans, your doctor may order tests. This may include: 1  Blood tests to check blood sugar level. People with acanthosis nigricans should be screened for diabetes and, although rare, cancer. Controlling blood glucose levels through exercise and diet often improves symptoms.
Skin changes