Jan R. Stockigt

Isolated hypoaldosteronism in adults. A renin-deficiency syndrome.

Abstract To clarify the mechanism causing isolated hypoaldosteronism in adults, we studied six patients with unexplained hyperkalemia. On a normal sodium intake, excretion of tetrahydrodeoxycorticosterone, tetrahydrocorticosterone, and 17-hydroxycorticoids was normal and increased normally with ACTH stimulation. Excretion of metabolites of aldosterone and 18-hydroxycorticosterone was subnormal or barely normal, and aldosterone excretion failed to respond normally to sodium depletion and ACTH. Plasma renin activity (PRA) and concentration were subnormal and failed to increase normally with upright posture and sodium depletion; furosemide increased PRA in only one patient. Restoration of normal serum potassium with cation exchange resin failed to increase PRA in the three patients studied. Plasma renin substrate was normal or slightly elevated. The patients studied differ from patients with Addisons disease and infants with enzymatic defects in aldosterone biosynthesis in whom PRA is increased. The data su...

Determination of Plasma Renin Concentration by Angiotensin I Immunoassay Diagnostic Import of Precise Measurement of Subnormal Renin in Hyperaldosteronism

Radioimmunoassay of angiotensin I was applied to the estimation of renin concentration after incubation of human plasma with an excess of renin substrate from plasma of anephric sheep. With this method markedly subnormal plasma renin levels were accurately measured. The technique was used in the study of 18 patients with proven aldosterone-producing adenoma (APA), 5 with hyperaldosteronism associated with bilateral adrenal hyperplasia, and 23 with essential hypertension. Plasma renin concentration (PRC) was extremely low in APA, and a significantly higher mean basal level of PRC was seen in hyperplastic aldosteronism (P <0.01). Postural responses were seen in both groups, and PRC was least variable during recumbency. Comparison of basal recumbent PRC with urinary aldosterone after three days of desoxycorticosterone acetate (DOCA) accentuated the distinction between APA and hyperplasia. It is suggested that the prediction of a distinct APA can best be made in patients with hyperaldosteronism when the exact extent of renin suppression is taken into account and when DOCA is used to assess suppressibility of aldosterone. While such evaluation may defer surgery in some patients with correctable hypertension, it may reduce the number with persistent hypertension after bilateral adrenalectomy.

Role of renin and aldosterone in hypertension due to a renin-secreting tumor☆

Abstract A renin-secreting renal tumor is a rare cause of curable hypertension characterized clinically by hypertension, hypokalemia, hyperaldosteronism and increased plasma renin activity (PRA). Prior subtotal adrenalectomy in such a patient allowed examination of the role of hyperreninemia in the absence of excessive aldosterone secretion. Hypertension was severe, but serum potassium and aldosterone production were normal. PRA was markedly increased under all conditions studied, with a persistent increase noted with changes in posture. Renal vein renin studies were critical in localizing the renal tumor, and unilateral nephrectomy resulted in a prompt fall in PRA to subnormal levels and dramatic cure of the hypertension. Renin content of the renal tumor was more than 500 times higher than in the adjacent kidney, and histologic studies confirmed that the tumor was of juxtaglomerular cell origin. This case demonstrates that severe hypertension can occur in this syndrome despite subtotal adrenalectomy and further illustrates an association of renin overproduction with a specific type of hypertension.

Selective Renal-Vein Renin Sampling in Hypertensive Patients with Segmental Renal Lesions

Abstract Selective intrarenal catheterization was used to obtain venous blood draining a lesion affecting only a segment of one kidney in nine hypertensive patients (four segmental infarcts, four renal-artery branch stenoses and one renin-secreting tumor). The main renal-vein renin ratio between the affected and contralateral kidneys (Ra/Rc) was > 1.5 in only four of nine patients (mean ratio ± S.E. 2.1 ± 0.5), whereas the ratio when the segmental sample (Rseg/Rc) was used was significantly higher: > 1.5 in all (4.5 ± 1.1). By contrast, neither plasma renin activity in segmental samples from normal areas of the affected kidney nor that in intrarenal samples of two patients with main renal-artery stenosis exceeded plasma renin activity of the affected kidney. Selective renal-vein renin sampling can specifically identify a localized source of renin that may be overlooked by main renal-vein sampling and facilitate the detection of patients with surgically remediable lesions. (N Engl J Med 290:1153–1157, 1974)

Segmental Renal-Vein Renin Sampling for Segmental Renal Infarction: Studies in a Hypertensive Patient

Abstract Segmental renal vein renin sampling identified a localized high renin source in a patient with a 9-year history of hypertension associated with a segmental renal infarct. The peripheral le...