Association of Papillary Thyroid Carcinoma with Primary Aldosteronism

Abstract

Objective The association of primary aldosteronism (PA) with thyroid disease has already been suggested. The aim of this study was to examine the presence of PA in patients with papillary thyroid carcinoma (PC) and to characterize such PC patients with PA. Methods We examined the presence of PA in 81 consecutive patients with PC, whose random sitting blood pressure (BP) was ≥140/90 mmHg in the office (n= 68), who had an incidental adrenal tumor or adrenal enlargement (n=9), or who showed hypokalemia (n=4). Thirty-one of these 81 patients had been treated with anti-hypertensive drugs. The plasma aldosterone concentration (PAC) and plasma renin activity (PRA) were first measured before operation in 16 patients and after operation in 65 patients. PA was diagnosed according to the guidelines of the Japan Endocrine Society. Results Forty patients with PC with a random PAC/PRA ratio of over 200 were subjected to a further study (12 of these patients had been treated with anti-hypertensive drugs). Ultimately, 15 patients with PC were diagnosed with PA. Adrenal venous sampling was done in 9 out of 15 patients with PC associated with PA. No patients were diagnosed as having unilateral lesions. Among the 15 patients, white-coat hypertension was observed in 5 patients, and normotension was observed in 1 patient. Conclusion These findings suggest that the prevalence of PA may be high among patients with PC. An active examination is needed to detect PA, as its signs and symptoms may be mild in patients with PC associated with hypertension.

Keywords: papillary thyroid carcinoma; primary aldosteronism; white-coat hypertension.

Figure.

Flow chart of the study. PC: papillary thyroid carcinoma, PAC: plasma aldosterone concentration, PRA: plasma renin activity, ARB: angiotensin II receptor blocker, CCB: calcium channel blocker, CCT: captopril-challenge test, UFT: upright furosemide-loading test, SLT: saline-loading test, OST: oral salt-loading test, (+): positive result, (-): negative result