Doctors always refer to a clinical picture as a syndrome when it is accompanied by numerous different symptoms. In the case of Cushing's syndrome, the number of possible symptoms is particularly high. In addition to the comparatively common Cushing's syndrome I, medicine also distinguishes between variations II and III.
Basically, this disease is a series of physical changes that lead to a considerable reduction in immune activity and aesthetics. It usually develops gradually over several years. Only rarely do those affected notice the onset of muscle atrophy or the abnormal accumulation of fat on the trunk of the body during this time.
The cause of Cushing's syndrome is always a high concentration of cortisol or cortisone in the human body. This is a vital hormone that performs numerous tasks. It mainly activates degradative metabolic processes and thus provides the body with a large number of energy-rich compounds. In this way, it provides the body with the energy it needs in dangerous situations. This is why cortisol is often referred to as the stress hormone. However, medicine distinguishes between four particular forms of this syndrome. These are
- exogenous Cushing's syndrome
- endogenous Cushing's syndrome
- ACTH-dependent Cushing's syndrome
- primary Cushing's syndrome
Exogenous Cushing's syndrome is usually caused by drug therapy with cortisone. This substance is used to combat numerous diseases due to its immunosuppressive and anti-inflammatory properties. It plays a key role in the treatment of asthma, autoimmune diseases and chronic intestinal diseases, among others. As a rule, the doctor administers the active ingredient directly into the patient's bloodstream. In some cases, however, this results in a drastic overdose. The syndrome immediately unfolds its destructive effect when the so-called Cushing's threshold is exceeded. For this reason, it is important that cortisone therapy is always carried out under medical supervision.
Endogenous Cushing's syndrome, on the other hand, develops without the addition of cortisone. In this rare variant of the disease, too much cortisol is produced in the adrenal glands. In healthy people, the production of this hormone is controlled by complex processes in the pituitary gland. This produces the messenger substance ACTH, which sends a production-increasing signal to the adrenal cortex. However, the formation of ACTH is dependent on the concentration of CRH. The more CRH is produced by the hypothalamus, the higher the production of ACTH. Cortisol inhibits the formation of CRH and thus creates a stable cycle. In endogenous Cushing's syndrome, this cycle is interrupted at various points.
ACTH-dependent Cushing's syndrome is a special form of endogenous Cushing's syndrome. It is triggered by a small tumor in the pituitary gland, which ensures a permanent production of ACTH. Primary Cushing's syndrome, on the other hand, is usually associated with a tumor directly in the adrenal cortex. In some cases, there is also excessive growth of the adrenal tissue. As a result, this type of Cushing's syndrome can also develop without a malignant cancer.
Cortisol fulfills numerous different tasks in the body. For this reason, Cushing's syndrome triggers a wide range of symptoms. There is always a massive redistribution of fat towards the center of the body. This malfunction is known as truncal obesity. Furthermore, body fat is also deposited on the face and between the shoulders in people with this disease. This results in a round, full moon face and the so-called bull neck. Regardless of weight, these regions are always filled with fat pads, while the arms and legs remain completely slim. In addition, particularly high cholesterol levels are also measured.
By Ozlem Celik, Mutlu Niyazoglu, Hikmet Soylu and Pinar Kadioglu - http://mrmjournal.biomedcentral.com/articles/10.1186/2049-6958-7-26, CC BY 2.5, Link
At the same time, there is an increase in insulin production and a higher concentration of sugar in the blood. This results in blood values that are very similar to diabetes. For this reason, Cushing's syndrome often goes unnoticed. However, it is clearly noticeable due to the constant feeling of thirst and frequent urination. It is also characterized by a rapid breakdown of muscle fibres and bone tissue. This results in both permanent bone loss and pathological muscle weakness.
The skin is also increasingly damaged by Cushing's syndrome. After a short time, so-called parchment skin develops. This medical term describes a very thin skin that is damaged by even the slightest application of force. In addition, red streaks often form on the abdomen, which are accompanied by acne and boils. Finally, wound healing in particular is very slow. Most people also suffer from constant high blood pressure. In addition to an extremely high susceptibility to infections, mental illnesses also occur in some cases. These include reduced potency in men and masculinization in women.
Even experienced specialists do not always find it easy to diagnose Cushing's syndrome. It is therefore crucial that the treating physician recognizes the connection between all the symptoms and interprets this correctly. This allows a physical examination to be initiated. Together with a series of different tests, a questionnaire regarding the patient's medical history will finally shed light on the origin and nature of the disease.
In most cases, the collection of urine over a period of 24 hours forms the core of the examination. In this way, the doctor can clearly determine the concentration of cortisol released. In addition, the so-called dexamethasone inhibition test has also become established in practice. A doctor uses this to determine the exact origin of a disruption in the cortisol production control loop. Ultimately, doctors carry out a CRH test as standard. This is very similar to the dexamethasone inhibition test, but primarily looks at the concentration of CRH in the body.
In exogenous Cushing's syndrome, only the dose of cortisone administered is gradually reduced. Treatment of endogenous Cushing's syndrome is more difficult, however, as the cause of the disease must be treated. This is usually a malignant or benign tumor. This must be surgically removed in order to reduce cortisol production. Numerous medications are also used to support the treatment. If neither procedure is effective, most specialists prescribe comprehensive radiotherapy or chemotherapy.
