If a child has acanthosis nigricans, but has tested negative for diabetes, what are some other causes of this?

Acanthosis nigricans (AN) is often associated with insulin resistance and obesity. It is more common in people with darkly pigmented skin than in lighter skinned people. There is a benign, inherited type, usually in thinner people and this can occur in several family members. In association with obesity, polycystic ovaries, androgen excess conditions, hypertension and hyperlipidemia, it is often related to insulin resistance. Acanthosis nigricans can be confused with conditions where there is excess cortisone production (Cushing’s syndrome or Cushing’s disease) since both involve hyperpigmentation. Disorders such as lupus, scleroderma, Sjogren syndrome or Hashimoto’s thyroiditis rarely also are associated with AN. Medications such as high doses of niacin or nicotinic acid, high doses of corticosteroids and estrogens such as stilbestrol and oral contraceptives also rarely can e associated with AN. Pituitary and adrenal adenomas, as well as many kinds of cancers (i.e. adenocarcinomas), sometimes are associated with AN.

SB