Cushing’s disease is a rare subset of Cushing’s syndrome, an endocrine disorder caused by prolonged exposure of the body’s tissues to high levels of cortisol. Cushing’s disease is caused specifically by a pituitary tumor secreting adrenocorticotropic hormone (ACTH).
Signs and Symptoms
The symptoms related to Cushing’s disease and Cushing’s syndrome are the same, since both are related to an excess of cortisol. These symptoms may include:
- Fullness and rounding of the face
- Added fat on back of neck
- Easy bruising of the skin
- Abdominal striae
- Excessive weight gain, most marked in the abdominal region, while the legs and arms remain thin
- Red cheeks
- Excess hair growth on the face, neck, chest, abdomen and thighs
- Generalized weakness and fatigue
- Wasting of muscles, most noticeably in the upper thighs.
- Menstrual disorders
- Decreased fertility and/or sex drive
- High blood pressure that is often difficult to treat
- Diabetes mellitus, often severe
- Mood and behavior disorders
- Macroadenomas, which can lead to
- Vision loss
- Hypopituitarism
- Elevated blood prolactin levels
Diagnosis
In general, the first step in making the diagnosis is establishing excessive blood cortisol (i.e. Cushing’s syndrome). This typically is done by hormone testing. After this diagnosis is established, an MRI is obtained to determine if a pituitary tumor is visible. In Cushing’s disease, typically microadenomas are found. If no tumor is visible, then inferior petrosal sinus sampling is indicated.
Diagnostic tests include:
- Hormone testing
- Magnetic resonance imaging (MRI) scan
- Inferior petrosal sinus sampling
Management and Treatment
Surgically removing the pituitary adenoma offers the only long-term cure of Cushing’s disease. There are medications that inhibit the adrenal gland’s production of cortisol. In some patients, these medications can effectively reduce the symptoms related to excessive cortisol when surgery fails to completely remove the tumor or when medication is necessary before surgery (e.g., a patient who is very ill). In some cases, surgeons may not be able to remove the tumor surgically. Radiation therapy can be very effective in controlling the growth of these tumors. A consequence of radiation treatment is that it can cause delayed pituitary failure. This typically occurs several years after treatment, and therefore continued long-term follow-up with an endocrinologist is important. Hormone replacement may be required.
Clinical Trials
For a full list of clinical trials relating to Cushing’s disease, go here.
Resources
Cushing’s Support and Research Foundation
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