Cushing syndrome is a series of symptoms triggered by a permanently elevated cortisol level. A distinction is made between endogenous and exogenous forms.
The endogenous form is referred to as "Cushing's disease" is distinct from "Cushing's syndrome". Here an overproduction of the adrenocorticotropic hormone (ACTH) in the anterior pituitary gland occurs, resp. the overproduction of corticotropin releasing hormone (CRH) in the hypothalamus. Thus, the amount of cortisol is not critical, but a central overproduction of "liberins" or glandotrophic hormones, which provoke a secondary overproduction of cortisol. However, ectopic ACTH-producing tumors may also be the cause.
Another possible cause is adrenal cortex tumors, which are responsible for cortisol formation. In rare cases, CS is caused by genetic disorders such as Li-Fraumeni syndrome. Most cases, however, are a form of the exogenously elicited Cushing's syndrome, which is usually caused iatrogenically by a high dose of glucocorticoids.
Characteristic symptoms include weight gain on the trunk, face (full moon face) and neck (fat pad in the neck, "bull's neck"), and an unnatural abdominal fat build-up with simultaneously slim arms and legs.
Patients are also prone to haemorrhage. Furthermore, violet striae, hypertension, muscle weakness and diabetes (so-called steroid diabetes) occur. Patients suffer from osteoporosis, poor wound healing, parchment skin, acne, erectile dysfunction, menstrual irregularities, hirsutism, and an increased susceptibility to infection. Often patientes also suffer from psychological symptoms such as depression or irritability.
In children, Cushing syndrome is characterized by a decreasing rate of growth and an abnormal weight gain. After the elimination of the cause, most of the symptoms of Cushing's syndrome regress. Untreated, the life expectancy is reduced. The incidence maximum is between 25 and 40 years.