Wide Variability in Catecholamine Levels From Adrenal Venous Sampling in Primary Aldosteronism

Area of Science:

• Endocrinology
• Nephrology
• Surgical Oncology

Background:

• Adrenal venous sampling (AVS) is crucial for differentiating unilateral and bilateral primary aldosteronism.
• Its utility in determining laterality for pheochromocytoma, especially with bilateral adrenal masses, remains unclear.

Purpose of the Study:

• To establish normal ranges for adrenal vein (AV) epinephrine and norepinephrine levels in patients without pheochromocytoma.
• To assess the potential limitations of AVS in diagnosing pheochromocytoma laterality.

Main Methods:

• Retrospective review of 172 patients undergoing AVS for primary aldosteronism (2009-2019).
• Exclusion of patients with pheochromocytoma.
• Measurement of aldosterone, cortisol, epinephrine, and norepinephrine from inferior vena cava, left adrenal vein, and right adrenal vein.

Main Results:

• Significant differences observed in median epinephrine (LAV vs. RAV, P=0.024) and norepinephrine (LAV vs. RAV, P=0.002) levels.
• Elevated median epinephrine levels in LAV (3811 pg/mL) and RAV (2897 pg/mL) compared to IVC (19 pg/mL).
• Elevated median norepinephrine levels in LAV (1450 pg/mL) and RAV (786 pg/mL) compared to IVC (325 pg/mL).

Conclusions:

• AVS reveals a broad spectrum of "normal" adrenal vein catecholamine levels in individuals without pheochromocytoma.
• These wide ranges may restrict the effectiveness of AVS in pinpointing the source of pheochromocytoma when bilateral adrenal nodules are present.