Primary aldosteronism can be categorized into 2 main subtypes: aldosterone-producing adenoma (APA) and idiopathic hyperaldosteronism. The treatment strategies for these 2 subtypes differ markedly: APA requires surgical removal of the adenoma, whereas idiopathic hyperaldosteronism is managed with pharmacological therapy. Adrenal venous sampling (AVS) is the most widely used technique for diagnosing APA, but its results can be influenced by abnormal adrenal or tumor venous drainage.A 58-year-old female was admitted due to elevated blood pressure for over 20 years and persistent hypokalemia for 3 months, accompanied by reduced physical strength, nocturia (2-3 times per night, 200-300 mL each time), and poor sleep quality.The AVS results of the patient did not demonstrate lateralized aldosterone secretion. However, the patient's Kupers and Kobayashi predictive scores, as well as elevated levels of 18-hydroxycortisol and 11-deoxycorticosterone, all supported the presence of a unilateral APA. Retrospective analysis of contrast-enhanced adrenal computed tomography revealed a right adrenal adenoma with a solitary vein draining directly into the inferior vena cava. In addition, 68Ga-pentixafor positron emission tomography/magnetic resonance imaging supported the diagnosis of a right-sided APA.Right adrenalectomy was performed.At 1 and 3 months postoperatively, the patient exhibited complete clinical and biochemical remission.This case highlights that when there is discordance between AVS findings and clinical assessments (e.g., predictive models), a multifaceted approach incorporating predictive scores, 18-hydroxycortisol, 11-deoxycorticosterone levels, and 68Ga-pentixafor positron emission tomography/magnetic resonance imaging can facilitate accurate diagnosis and guide management decisions.Copyright © 2025 the Author(s). Published by Wolters Kluwer Health, Inc.