Cortisol is a hormone produced and secreted by the adrenal glands. The adrenals are a pair of triangular-shaped glands that sit atop each kidney. The adrenals secrete cortisol in response to another hormone, called ACTH, secreted from the pituitary gland, a pea-sized gland that lies just below the brain. In general, children have lower cortisol levels than adults.
Cortisol is a steroid hormone that has many different functions. According to Lab Tests Online, cortisol helps break down protein and glucose to make them available as energy for the body's tissues. It helps maintain blood pressure and your immune system. Cortisol levels fluctuate during the day, peaking in the morning and slowly decreasing throughout the day. Cortisol is also known as the stress hormone, in that, in stressful situations, it helps with the "fight-or-flight" response, increasing energy levels.
Low Cortisol in Children
Children with low cortisol levels may be suffering from adrenal insufficiency, a condition in which the adrenals do not produce enough cortisol. According to the National Institutes of Health, this can be due to primary adrenal insufficiency, also known as Addison's disease, in which the adrenal glands themselves are damaged and cannot secrete cortisol; or secondary adrenal insufficiency, due to the inability of the pituitary to secrete enough ACTH to stimulate the secretion of cortisol. Children with low levels may suffer from chronic fatigue, muscle weakness, weight loss, vomiting and low blood sugar.
High Cortisol in Children
High cortisol levels in children cause a condition called Cushing's syndrome. This can occur if the adrenals secrete too much cortisol or if the pituitary has uncontrolled secretion of ACTH. Cushing's can also develop when children take long-term steroid medications, or if they have a tumor that secretes cortisol. Symptoms of Cushing's syndrome in children include high blood pressure, high levels of glucose in the bloodstream, fatigue and weakness, irritability or anxiety, excess weight gain around the waist and the development of a fatty hump between the shoulder blades.
Congenital Adrenal Hyperplasia
According to the Merck Manual for Healthcare Professionals, congenital adrenal hyperplasia is a group of inherited disorders in which babies are unable to make enough cortisol and other adrenal hormones. This results in an increase in other hormones called androgens. Androgens are responsible for the development of male characteristics. Girls with congenital adrenal hyperplasia can have ambiguous sex organs without distinct female sexual features. Boys can have excess body hair. Other symptoms for both sexes include salt craving, salt wasting and dehydration.
Treatment of abnormal cortisol levels in children depends on the cause. Low cortisol can be treated with steroid supplements. When the child is sick, the doses of these steroids need to be increased. The treatment of Cushing's syndrome may include surgery, chemotherapy or the use of drugs that block the action of the excess cortisol. Children with congenital adrenal hyperplasia need replacement of steroids and other adrenal hormones. Girls may require reconstructive surgery of the affected sex organs.