These are normally produced by the adrenal gland, but damage can cause levels to drop.

BBC: Living with Addison's disease

The disease is normally caused by the body's own immune system turning on the adrenal gland, but cancer and tuberculosis can also trigger the condition.

BBC: Living with Addison's disease

The patient was a woman with a large tumor in the adrenal gland atop her right kidney, and I had decided to remove it using a laparoscope.

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