Feasibility of Iodine-131 6β-Methyl-Iodo-19 Norcholesterol (NP-59) Scintigraphy to Complement Adrenal Venous Sampling in Management of Primary Aldosteronism: A Case Series

Strategies for subtyping primary aldosteronism

Adrenal venous sampling (AVS) is a crucial method for the lateralization of primary aldosteronism (PA). It is advised to halt the use of the patient's antihypertensive medications and correct hypokalemia prior to undergoing AVS. Hospitals equipped to conduct AVS should establish their own diagnostic criteria based on current guidelines. If the patient's antihypertensive medications cannot be discontinued, AVS can be performed as long as the serum renin level is suppressed. The Task Force of Taiwan PA recommends using a combination of adrenocorticotropic hormone stimulation, quick cortisol assay, and C-arm cone-beam computed tomography to maximize the success of AVS and minimize errors by using the simultaneous sampling technique. If AVS is not successful, an NP-59 (131 I-6-β-iodomethyl-19-norcholesterol) scan can be used as an alternative method to lateralize PA. We depicted the details of the lateralization procedures (mainly AVS, and alternatively NP-59) and their tips and tricks for confirmed PA patients who would consider to undergo surgical treatment (unilateral adrenalectomy) if the subtyping shows unilateral disease.

Synthesis of Radioiodinated Compounds. Classical Approaches and Achievements of Recent Years

This review demonstrates the progress in the synthesis of radioiodinated compounds over the past decade. The possibilities and limitations of radiopharmaceuticals with different iodine isotopes, as well as the synthesis of low and high molecular weight compounds containing radioiodine, are discussed. An analysis of synthesis strategies, substrate frameworks, isolation methods, and metabolic stability, and the possibility of industrial production of radioiodinated organic derivatives which can find applications in the synthesis of drugs and diagnostics are presented.

Bilateral Adrenalectomy in a Patient With Refractory Primary Aldosteronism Due to Adrenal Hyperplasia

Primary aldosteronism (PA) is a frequent cause of secondary hypertension. The main cause of PA is bilateral adrenal hyperplasia, and treatment is usually medical with mineralocorticoid receptor antagonists (MRAs) such as spironolactone or eplerenone. In this paper, we present a rare clinical case of a middle-aged female with refractory arterial hypertension and hypokalemia that complementary medical tests confirmed PA due to bilateral hyperplasia, and despite a maximum dose of spironolactone and oral potassium supplements, there was no clinical response. Because of this, finally, the patient needed surgical treatment based on bilateral adrenalectomy, which was effective. This is unusual and poorly described in the medical literature.

Apparent failed and discordant adrenal vein sampling: A potential confounding role of cortisol cosecretion?

OBJECTIVE

Adrenal vein sampling (AVS) and computed tomography (CT) often show confusingly discordant lateralisation results in primary aldosteronism (PA). We tested a biochemical algorithm using AVS data to detect cortisol cosecretion as a potential explanation for discordant cases.

DESIGN

Retrospective analysis from a large PA + AVS database.

PATIENTS

All patients with PA and AVS, 2005-2020.

MEASUREMENTS

An algorithm using biochemical data from paired AVS + CT images was devised from physiological first principles and informed by data from unilateral, AVS-CT concordant patients. The algorithm involved calculations based upon the expectation that low cortisol levels exist in adrenal vein effluent opposite an aldosterone-and-cortisol-producing adrenal mass and may reverse lateralisation due to inflated aldosterone/cortisol ratios.

MAIN OUTCOMES

The algorithm was applied to cases with discordant CT-AVS lateralisation to determine whether this might be a common or explanatory finding. Clinical and biochemical characteristics of identified cases were collected via chart review and compared to CT-AVS concordant cases to detect evidence of biological plausibility for cortisol cosecretion.

RESULTS

From a total of 588 AVS cases, 141 AVS + CT pairs were clear unilateral PA cases, used to develop the three-step algorithm for AVS interpretation. Applied to 88 AVS + CT discordant pairs, the algorithm suggested possible cortisol cosecretion in 40%. Case review showed that the proposed cortisol cosecretors, as identified by the algorithm, had low/suppressed adrenocorticotropic hormone levels, larger average nodule size and lower plasma aldosterone.

CONCLUSIONS

Pending external validation and outcome verification by surgery and tissue immunohistochemistry, cortisol cosecretion from aldosteronomas may be a common explanation for discordant CT-AVS results in PA.