Hyperaldosteronism diagnosis

Diagnosis of primary hyperaldosteronism As initial diagnostic measure to provide presumptive evidence of primary hyperaldosteronism in patients on normal diets, as follows ... 

Long test-400 mg/day for 3 to 4 weeks. Correction of hypokalemia and hypertension provides presumptive evidence for diagnosis of primary hyperaldosteronism. 

Short test-400 mg/day for 4 days. If serum potassium increases but decreases when spironolactone is discontinued, consider a presumptive diagnosis of primary hyperaldosteronism. 

When used for diagnosis of primary hyperaldosteronism, positive results are (long test) correction of hyperkalemia and hypertension (short test) serum potassium increases during administration, but falls upon discontinuation... 

Most patients with autonomous aldosterone overproduction are hypokalemic, but most patients with hypokalemia do not have primary aldosteronism. In hyperaldosteronism, urinary potassium excretion is inappropriately high, and a random urine potassium >30mraol/L is usually indicative of primary aldosteronism or some type of mineralocorticoid excess condition. If hypokalemia can be shown to he due to nonrenal potassium loss, the diagnosis of aldosteronism does not need to be considered further. ... 

The absolute diagnosis is relatively easy based on ctinical findings and pertinent laboratory findings. However, as in Cushing s disease, the discovery of the underlying etiology is mandatory to ensure proper treatment. Table 74—6 lists the various abnormalities that must be ruled out when suspicion of hyperaldosteronism is high. 

The diagnosis of hyperaldosteronism may be made in the hypokalacmic patient if the serum aldosterone level exceeds the upper limit of nomial or if the level is persistently inappropriate to the scrum potassium. In primary hyperaldosleronism. where the excess aldosterone arises from an adrenal adenoma, the levels of plasma renin will be low. 

Juxtaglomerular cell tumor is essentially discovered in the second decade of life, when hypertension and hyperaldosteronism lead to the diagnosis. MRI combined with MR angiography may be proposed in this context to detect the tumor and to evaluate the status of the renal artery (Agrawal et al. 1995). 

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