Acanthosis nigricans is a disorder of hyperpigmentation (an increase of the dark pigment melanin) in the skin. This condition can occur in any breed secondary to other skin disorders, but the inherited primary form is seen almost exclusively in the dachshund. Acanthosis nigricans causes skin lesions that are darker than the skin around them. The lesions have a velvety feel. The lesions often form in the folds along the neck, armpits, groin, knuckles, between the legs, at the elbow, under the breasts, and around the belly button. 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. Sometimes, the lips, palms, soles of feet, or other areas may be affected.
The exact cause of this acanthosis nigricans is unknown. It can be a genetic (inherited) condition. When inherited, it is not considered dangerous. However it is sometimes associated with obesity, diabetes, cancer and certain drugs. All of these conditions can be considered potentially dangerous. Acanthosis nigricans can affect otherwise healthy people, or it can be associated with medical problems. Some cases are genetically inherited. It is most common among people of African descent. Obesity can lead to acanthosis nigricans, as can many endocrine disorders. It is frequently found in people with diabetes. Some drugs, particularly hormones such as human growth hormone or oral contraceptives ("the pill"), can also cause acanthosis nigricans. People with cancers of the gastrointestinal or genitourinary tracts or with lymphoma can also develop severe cases of this acanthosis nigricans.
Acanthosis nigricans is a skin condition that signals high insulin levels in the body. Insulin is produced by an organ called the pancreas. Insulin is important because it helps “carry” the glucose or sugar to the cells in your body. High insulin levels indicate that the body is resisting the insulin that is being produced. As a result, the pancreas produces more insulin than needed, and through time, it can stop producing enough insulin to take the glucose to the cells in the body. Acanthosis Nigricans is important because these markings can help identify persons who run the risk of developing diabetes in the future.
Acanthosis nigricans is important because of the increasingly alarming rates of persons developing type 2 diabetes. Until recently, it was believed that children could not develop Type 2 diabetes. However, children can. Acanthosis nigricans screenings can help identify persons who have high insulin levels and who may be at-risk for developing the disease. Once identified, the necessary measures to lower the insulin levels and reduce the risk of developing diabetes can be taken. Exercise and nutrition will help the body become more sensitive to insulin and lower insulin levels. Similarly, the acanthosis nigricans markers will begin to fade.
The main aim of treatment lies in terminating the underlying disease process. Treatment of the lesions of acanthosis nigricans is for cosmetic reasons only. Correcting hyperinsulinemia may also help control the condition. If the condition is caused due to an external cause like the side effect of a medication, it will go away once the medicine is stopped. But if is caused by a cancer, there is nothing much that can be done. When AN is caused by obesity, weight management is key. Topical applications do make a difference, so do oral agents.
Though the treatment procedure helps in controlling the condition, it comes with certain side effects like stretch marks and thinning of the skin and birth defects in pregnant women who use retinoids. Acanthosis nigricans may not be life threatening but it sure indicates an underlying condition that may prove fatal if ignored. Therefore it is necessary for the examiner to make a proper diagnosis so that the patient can be treated accordingly and any new or worsening symptoms can be controlled before they assume a malignant form.