SFE/SFHTA/AFCE Consensus on Primary Aldosteronism, part 2: First diagnostic steps.

Primary aldosteronism (PA) is a condition where the adrenal glands produce excess aldosterone, potentially causing hypertension and electrolyte imbalances. Diagnosis of PA requires a high-sensitivity screening method to avoid missing cases. Prior research has shown that serum potassium, plasma aldosterone, and urinary aldosterone have lower sensitivity and higher variability compared to the aldosterone-to-renin ratio (ARR). However, the optimal conditions for ARR measurement and interpretation remain unclear. That uncertainty drove the need for standardized diagnostic protocols. No prior work had resolved how to handle low renin values or how to convert measurements across units. This gap motivated the development of a consensus on ARR screening thresholds and conditions. Researchers propose that ARR is more reliable than alternative measures, but the exact parameters for its use remain debated. The need for consistent diagnostic criteria is critical for accurate PA identification.

This study aims to establish standardized diagnostic procedures for primary aldosteronism using the aldosterone-to-renin ratio (ARR). The goal is to define the conditions under which ARR measurements should be taken and to propose threshold values for interpreting results. The researchers focus on ensuring high sensitivity and negative predictive value in PA screening. They also address how to handle low renin values and unit conversions. The study seeks to clarify the diagnostic workflow for suspected PA cases. By setting clear guidelines, the authors hope to improve diagnostic accuracy and reduce false negatives. They emphasize the importance of standardization in ARR measurement protocols. The study also aims to provide practical guidance for clinicians managing hypertension.

The diagnostic approach involves measuring plasma aldosterone (PA) and plasma renin activity (PRA) or direct plasma renin (DR) to calculate the aldosterone-to-renin ratio (ARR). These measurements must be taken under specific conditions: in the morning, after a 2-hour post-awakening period, in a sitting position, with normal salt intake and serum potassium levels. The study outlines standard conditions for ARR screening to ensure consistency. It also defines a minimum aldosterone level of 240 pmol/l (90 pg/ml) for ARR screening eligibility. Low renin values are adjusted to a baseline threshold to prevent false positives. The researchers propose ARR thresholds based on measurement units and conversion factors. The study includes guidelines for interpreting ARR results and determining the next steps in PA diagnosis.

The study proposes that ARR screening should be conducted only if plasma aldosterone exceeds 240 pmol/l (90 pg/ml). Low renin values are adjusted to a minimum threshold to avoid misleading results. ARR thresholds vary depending on the units used for renin measurement. The researchers suggest a conversion factor for direct plasma renin (DR) values from pg to mIU. If ARR exceeds the threshold, primary aldosteronism is suspected, and further testing is recommended. If ARR is below the threshold or plasma aldosterone is below 240 pmol/l on two occasions, PA is ruled out. The study emphasizes the importance of standardized measurement conditions for accurate ARR interpretation. These findings provide a framework for consistent PA screening and diagnosis.

The authors propose standardized ARR screening protocols for primary aldosteronism diagnosis. They emphasize the importance of measuring ARR under specific conditions to ensure accuracy. The study suggests that ARR is more reliable than alternative measures like serum potassium or plasma aldosterone. They define a minimum aldosterone level of 240 pmol/l (90 pg/ml) for screening eligibility. Low renin values are adjusted to a baseline threshold to prevent false positives. The researchers propose ARR thresholds based on measurement units and conversion factors. If ARR exceeds the threshold, further investigation is recommended. If ARR is below threshold or plasma aldosterone is low on two measurements, PA is excluded.