The development of a dark, velvety ring, or hyperpigmentation, around one's neck is not always a sign that the individual needs to pay more attention to hygiene. Often, it is an indicator of an underlying health condition. While these dark patches may appear in healthy persons, the dark rings or patches that appear on skin, known as acanthosis nigricans, are a hallmark of many insulin-related problems. The good news is that, except in very rare cases, this condition disappears when the underlying causes are treated.
Acanthosis nigricans is often present in individuals who have a higher level of insulin than the average person, and this excess insulin triggers a production of cells that produce pigmentation, or melanocytes. A high insulin level may be the result of several conditions, including diabetes, pre-diabetes and insulin resistance, sometimes known as metabolic syndrome, or syndrome X. Insulin resistance is becoming increasingly more common, and in female patients it is often a result of polycystic ovarian syndrome, also known as PCOS. While the cause of diabetes is fairly well known, the duo of insulin resistance and PCOS are fairly enigmatic, with poor diet, obesity, genetic predisposition, medication and the environment each cited as the cause. Which of the cited risk factors are a cause of insulin resistance, and which are symptoms, is still unclear.
Acanthosis nigricans may be present on any part of the body, but is typically found in areas where skin overlaps or folds, such as the back of the neck, underarms, groin or stomach. In rare cases, it is found on other parts of the body, such as the backs of hands or feet. This symptom is cited as occurring most commonly in people of African descent, as well as those under 40, but can be found in any segment of the population.
While overproduction of insulin is the main cause of acanthosis nigricans, it may also be caused by other problems, usually those relating to the endocrine, or hormonal, system. This condition has been observed in people with Addison's disease, Cushing's disease and hypothyroidism, as well as those with disorders of the pituitary gland and those undergoing hormonal growth therapy. In rare cases, the condition manifests as a symptom of malignant cancer, usually of the stomach or uterus. If the typical risk factors for insulin-related problems are not observed, it may be necessary for doctors to perform further diagnostic testing to rule out more serious conditions.
Treatment of acanthosis nigricans often includes a change in diet, a change in or addition of medications, and cosmetic treatments to lessen the appearance of the affected areas. Because of the indication of more serious medical problems, individuals who believe they have this disorder should seek treatment from a dermatologist, endocrinologist or family physician. Medical professionals can often confirm that the problem is, in fact, acanthosis nigricans by merely looking at the area of skin in question, and then running diagnostic tests to determine the cause accordingly.