In Conn syndrome (synonyms: Aldosteronom; Conn’s disease; primary hyperaldosteronism; ICD-10-GM E26.0: Primary hyperaldosteronism) is a form of primary hyperaldosteronism (PHA). It is characterized by overproduction of aldosterone in the adrenal cortex due to an adenoma (benign tumor) without activation by the renin-angiotensin-aldosterone system (RAAS). Aldosterone is a mineralocorticoid that regulates fluid and electrolyte (blood salt) balance with other hormones such as renin and angiotensin.
From the classic hypokalemic hyperaldosteronism (there is a potassium deficiency) one can distinguish normokalemic hyperaldosteronism (the potassium levels are normal), which is diagnosed much more frequently.
The group of forms of primary hyperaldosteronism* includes:
- Idiopathic hyperaldosteronism (IHA) with bilateral adrenocortical hyperplasia (65%).
- Aldosterone-producing adenoma (APA) (Conn syndrome; 30%).
- Primary unilateral adrenal hyperplasia (3%).
- Aldosterone-producing adrenocortical carcinoma (malignant tumor; 1%).
- Aldosterone-producing tumor of the ovary/ovary (<1%).
- Glucocorticoid-suppressible primary hyperaldosteronism (GSH; synonym: dexamethasone-suppressible hyperaldosteronism, glucocorticoid-remediable aldosteronism, GRA).
- Familial form (familial hyperaldosteronism type I; <1%).
- Familial hyperaldosteronism type II, type III (frequency: very rare).
- Ectopic aldosterone-producing adenomas/carcinomas (< 0.1%).
* In primary hyperaldosteronism (Conn syndrome), the adrenal cortex produces increased aldosterone without activation by the renin-angiotensin-aldosterone system (RAAS). In secondary hyperaldosteronism, the adrenal cortex produces increased aldosterone through chronic activation of the renin-angiotensin-aldosterone system (RAAS).
Sex ratio: Men and women are equally affected.
Frequency peak: The disease occurs predominantly between the ages of 30 and 50.
The prevalence (disease frequency) of normokalemic Conn syndrome is 5-13% of hypertensives (patients with high blood pressure). Thus, this form represents the most common cause of secondary hypertension. The prevalence of classic hypokalemic Conn syndrome is < 0.5% of hypertensive patients (in Germany).
Course and prognosis: In the early stages of the disease, hardly any symptoms are recognizable. Hypertension, as the main symptom of Conn syndrome, can damage the kidneys, heart, vessels, and eyes as it progresses. The majority of those affected die from coronary heart disease (CHD), heart failure (cardiac insufficiency) or myocardial infarction (heart attack). Consequently, the focus of therapy is to eliminate the cause of primary hyperaldosteronism and to achieve optimal blood pressure control.
