Low renin hypertension and mineralocorticoid excess

Low renin hypertension and mineralocorticoid excessP-639: Low renin hypertension and mineralocorticoid excess Mineralocorticoid excess has being increasingly diagnosed in arterial hypertension and is known to be associated with a low renin condition; however it may escape diagnosis in the absence of overt hypokalemia and aldosteronism. Aim of the study was to assess in hypertensive patients the relationship between a low renin profile and adrenal abnormalities evaluated by CT and adrenocortical scintigraphy. CT of the adrenal regions without contrast media injection was performed in 34 normokalemic hypertensive patients with low PRA levels(≤0,65 ng/ml/hr) and either high-normal or mildly elevated aldosterone levels (range 120–220 pg/ml) and in a series of eight hypertensive patients with comparable aldosterone but normal PRA levels (>0,65 ng/ml/hr). All patients had their antihypertensive treatment withdrawn and were under no salt restriction for at least one week at the time of laboratory examination. Iodomethyl-Nor-cholesterol adrenal scintigraphy under ACTH suppression by oral desamethasone was performed only in positive CT studies. Adrenal CT was normal in the control population but showed either bilateral or unilateral abnormalities in 20 low renin patients: bilateral hyperplasia (n=8), unilateral hyperplasia (n=3), unilateral nodule (n=9). Scintigraphy showed hyperfunctioning glands in 11 out of 16 patients who underwent the examination (8 bilaterally, 3 unilaterally). A low renin profile with inappropriately mantained aldosterone secretion in arterial hypertension may suggest adrenocortical hyperplasia or adenoma. A screening by means of adrenal CT is indicated, to be followed in the positive cases by adrenal scintigraphy or adrenal vein sampling. This workup could allow a correct diagnosis and tailored treatment.