Endocrine Abstracts

Introduction: This problem has a major social and medical significance. The prevalence of secondary endocrine hypertension is around 40%, of which primary aldosteronism is up to 15% and is usually developed at working age. Despite of improvement of diagnostical two-step method of finding primary aldosteronism, none of these test results can be considered reliable because of false positive and false negative results. That’s why the problem of endocrine hypertension diagnosis especially primary aldosteronism is still very important. We made a research of the renin–angiotensin–aldosterone system (RAAS) and urinary aldosterone excretion in patients with arterial hypertension and adrenal tumors to improve diagnosis of primary aldosteronism.

Objective: To explore the renin–angiotensin–aldosterone system (RAAS) and 24-h urinary aldosterone excretion in patients with adrenal tumors and arterial hypertension.

Methods: We enrolled 59 patients with adrenal tumors in combination with arterial hypertension [blood pressure ≥ 140/90 mm Hg by antihypertensive drug classes, 85% females, age 52±12.5 years (mean±standard deviation)], who had hormone-producing adenomas (aldosterone-producing adenoma n=27, cortisol-producing adrenal adenoma n=8 and pheochromocytoma n=5) and non-functioning adrenal adenomas in combination with arterial hypertension (n=19). The RAAS (angiotensin II, angiotensinogen, prorenin) of plasma and serum is measured in peripheral blood by Enzyme Immunoassay, and aldosterone is determined in 24-hour urine by Enzyme Immunoassay.

Results: Patients with aldosterone-producing adenoma (n=27) in compared with non-functioning adrenal adenomas in combination with arterial hypertension (n=19) didn’t have different results of RAAS: angiotensin II (P=1.0, median 29.6 pg/ml, interquartile range 23.4–35.6), angiotensinogen (P=1.0, median 15.4 μg/ml, interquartile range 13.5–18.8) and prorenin (P=0.351, median 688.5 pg/ml, interquartile range 418–1133.5). Though 24-h urinary aldosterone level in patients with aldosterone-producing adenoma (n=27) were statistically significantly higher than in patients with non-functioning adrenal adenomas with arterial hypertension (n=19) (P=0.042, median 17.1 μg/day, interquartile range 9.6–31.1).

Conclusion: 24-h urinary aldosterone level may be diagnostically helpful in discriminating to clarify the diagnosis of primary aldosteronism, which, along with the definition of aldosterone-renin ratio (ARR) and confirmatory tests, can be a diagnostic criterion for diagnosing.