Conn's syndrome
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.
What is the duration of the hypertension? How and when was it detected?
Hypertension occurring at a young age is more likely to be secondary.
What is the severity of hypertension and treatments used to date?
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.
When was hypokalaemia first noted and which medications were they on at the time?
Severe hypokalaemia is rarely seen in the absence of underlying disease even with diuretic use.
Is there a relevant family history?
Essential hypertension commonly runs in families.
History of premature cardiovascular disease is also important to document in risk stratification.
Does the patient smoke?
All cardiovascular risks should be assessed in patients with newly diagnosed hypertension.
Any history of liquorice ingestion or herbal or alternative remedies?
These may mimic the biochemical picture of hyperaldosteronism.
Does the patient have muscle weakness and wasting? For example, can they climb the stairs or rise from a chair easily? Can they brush or dry their hair easily?
These questions are specifically seeking evidence of proximal myopathy.
Are there any features suggestive of thyroid disease?
Hypokalaemia may also occur in familial periodic paralysis, which may be associated with thyrotoxicosis, particularly in patients of Chinese ethnic origin.
Are any features suggestive of Cushing's syndrome?
Hypertension and hypokalaemia can also occur in Cushing's syndrome.
Adrenocortical adenomas can also occasionally co-secrete cortisol and aldosterone.
Would the patient consider a surgical treatment for their hypertension?
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.
Is the patient fit enough to consider a general anaesthetic?
Long standing severe hypertension may be associated with end organ damage including cardiomyopathy.
Does the patient have symptoms of end organ damage or other underlying conditions?
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.