Syndrome of hypertension and hypokalaemia caused by hyperaldosteronism. A diagnosis of Conn's may be caused by a unilateral adrenal adenoma or bilateral adrenal hyperplasia.
Hypertension occurring at a young age is more likely to be secondary.
Hypertension due to Conn’s syndrome is typically difficult to control on standard medications, for example calcium channel blockers or diuretics alone, but responds well to aldosterone antagonists.
Hypokalaemia is also exacerbated by diuretics.
Severe hypokalaemia is rarely seen in the absence of underlying disease even with diuretic use.
Essential hypertension commonly runs in families.
History of premature cardiovascular disease is also important to document in risk stratification.
All cardiovascular risks should be assessed in patients with newly diagnosed hypertension.
These may mimic the biochemical picture of hyperaldosteronism.
These questions are specifically seeking evidence of proximal myopathy.
Hypokalaemia may also occur in familial periodic paralysis, which may be associated with thyrotoxicosis, particularly in patients of Chinese ethnic origin.
Hypertension and hypokalaemia can also occur in Cushing's syndrome.
Adrenocortical adenomas can also occasionally co-secrete cortisol and aldosterone.
It is always important to determine the cause of secondary hypertension and confirm a biochemical suspicion of Conn’s to guide medical treatment. However, it is worth establishing the appropriateness of surgery at the outset to prevent costly localising investigations in some patients.
Long standing severe hypertension may be associated with end organ damage including cardiomyopathy.
End organ damage, for example retinopathy or vascular disease, tends to predict a poor surgical outcome.
Other causes of secondary hypertension, for example renovascular disease, coarctation of the aorta, or intrinsic renal disease, should always be sought and screened for if appropriate.