KCNJ5-Negative Primary Aldosteronism: Histopathology and Surgical Outcomes

Area of Science:

• Endocrinology
• Nephrology
• Surgical Oncology

Background:

• Unilateral primary aldosteronism (uPA) is a common, surgically treatable cause of secondary hypertension.
• KCNJ5 mutations are common in aldosterone-producing adenomas, but the prognosis for uPA without these mutations is less understood.
• Histopathology may offer insights into surgical outcomes for KCNJ5-negative uPA.

Purpose of the Study:

• To investigate the association between histopathologic subtypes of KCNJ5-negative uPA and postoperative outcomes.
• To determine if the HISTALDO consensus criteria can predict surgical success in patients with KCNJ5-negative uPA.

Main Methods:

• Analysis of 171 patients with KCNJ5-negative uPA who underwent adrenalectomy.
• Classification of adrenal histopathology into classical or nonclassical subtypes based on HISTALDO criteria.
• Assessment of postoperative outcomes at 12 months using the Primary Aldosteronism Surgical Outcome criteria.

Main Results:

• 52.6% of patients had classical histopathology, and 47.4% had nonclassical features.
• Complete clinical success was achieved in 40.9% of all patients.
• Classical histopathology was associated with significantly higher success rates (50%) compared to nonclassical (30.9%; P=0.01).
• Nonclassical histopathology, higher serum creatinine, and higher diastolic blood pressure independently predicted lower success rates.

Conclusions:

• Nonclassical adrenal histopathology is present in nearly half of KCNJ5-negative uPA cases and is linked to poorer surgical outcomes.
• Histopathologic classification is a valuable prognostic tool for KCNJ5-negative uPA.
• Integrating histology and genetics may enhance patient management for uPA.