Morphologically Normal-Appearing Adrenal Glands as a Prevalent Source of Aldosterone Production in Primary Aldosteronism.

BACKGROUND: Normal-appearing adrenal glands on cross-sectional imaging may still be the source of aldosterone production in primary aldosteronism (PA). METHODS: We evaluated the prevalence of aldosterone production among morphologically normal-appearing adrenal glands and the impact of this phenomenon on interpretations of localization studies and treatment decisions. We performed a retrospective cohort study of PA patients with at least 1 normal adrenal gland and reanalyzed contemporary studies to assess interpretations of imaging and adrenal venous sampling (AVS) at the individual patient and adrenal levels. RESULTS: Among 243 patients, 43 (18%) had bilateral normal-appearing adrenals and 200 (82%) had a unilateral normal-appearing adrenal, for a total of 286 normal-appearing adrenal glands. 38% of these normal-appearing adrenal glands were a source of aldosteronism on AVS, resulting in discordance between imaging and AVS findings in 31% of patients. Most patients with lateralizing PA underwent curative unilateral treatment (80%); however, curative treatment was pursued in 92% of patients who had concordant imaging-AVS results but in only 38% who had discordant results (P < 0.05). In young patients, imaging-AVS discordance was detected in 32% of those under 45 years and 21% of those under 35 years. Among 20 contemporary studies (including 4,904 patients and 6,934 normal-appearing adrenal glands), up to 64% of normal-appearing adrenals were a source of aldosteronism resulting in 31% of patients having discordant results. CONCLUSIONS: Morphologically normal-appearing adrenal glands are commonly the source of aldosterone production in PA, even among young patients. The lack of awareness of this issue may result in inappropriate treatment recommendations.

Adrenocorticotropic Hormone-Stimulated Adrenal Venous Sampling Underestimates Surgically Curable Primary Aldosteronism: A Retrospective Cohort Study and Review of Contemporary Studies.

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Intraindividual Variability of Aldosterone Concentrations in Primary Aldosteronism: Implications for Case Detection.

Primary aldosteronism is an underdiagnosed cause of hypertension. Although inadequate screening is one reason for underdiagnosis, another important contributor is that clinicians may inappropriately exclude the diagnosis when screening aldosterone concentrations fall below traditionally established thresholds. We evaluated the intraindividual variability in screening aldosterone concentrations and aldosterone-to-renin ratios, and how this variability could impact case detection, among 51 patients with confirmed primary aldosteronism who had 2 or more screening measurements of renin and aldosterone on different days. There were a total of 137 screening measurements with a mean of 3 (range 2-6) per patient. The mean intraindividual variability, expressed as coefficients of variation, was 31% for aldosterone and 45% for the aldosterone-to-renin ratio. Aldosterone concentrations ranged from 4.9 to 51 ng/dL; 49% of patients had at least one aldosterone measurement below 15 ng/dL, 29% had at least 2 aldosterone measurements below 15 ng/dL, and 29% had at least one measurement below 10 ng/dL. Individual aldosterone-to-renin ratios ranged from 8.2 to 427 ng/dL per ng/mL·hour; 57% had at least one ratio below 30 ng/dL per ng/mL·hour, 27% had at least 2 ratios below 30 ng/dL per ng/mL·hour, and 24% had at least one ratio below 20 ng/dL per ng/mL·hour. Aldosterone concentrations and aldosterone-to-renin ratios are highly variable in patients with primary aldosteronism, with many screening values falling below conventionally accepted diagnostic thresholds. The diagnostic yield for primary aldosteronism may be substantially increased by recalibrating the definition of a positive screen to include more liberal thresholds for aldosterone and the aldosterone-to-renin ratio.

Variability of Aldosterone Measurements During Adrenal Venous Sampling for Primary Aldosteronism.

BACKGROUND: Variability of aldosterone concentrations has been described in patients with primary aldosteronism. METHODS: We performed a retrospective cohort study of 340 patients with primary aldosteronism who underwent adrenal venous sampling (AVS) at a tertiary referral center, 116 of whom also had a peripheral venous aldosterone measured hours before the procedure. AVS was performed by the same interventional radiologist using bilateral, simultaneous sampling, under unstimulated and then stimulated conditions, and each sample was obtained in triplicate. Main outcome measures were: (i) change in day of AVS venous aldosterone from pre-AVS to intra-AVS and (ii) variability of triplicate adrenal venous aldosterone concentrations during AVS. RESULTS: Within an average duration of 131 minutes, 81% of patients had a decline in circulating aldosterone concentrations (relative decrease of 51% and median decrease of 7.0 ng/dl). More than a quarter (26%) of all patients had an inferior vena cava aldosterone of ≤5 ng/dl at AVS initiation. The mean coefficient of variation of triplicate adrenal aldosterone concentrations was 30% and 39%, in the left and right veins, respectively (corresponding to a percentage difference of 57% and 73%), resulting in lateralization discordance in up to 17% of patients if the lateralization index were calculated using only one unstimulated aldosterone-to-cortisol ratio rather than the average of triplicate measures. CONCLUSIONS: Circulating aldosterone levels can reach nadirs conventionally considered incompatible with the primary aldosteronism diagnosis, and adrenal venous aldosterone concentrations exhibit acute variability that can confound AVS interpretation. A single venous aldosterone measurement lacks precision and reproducibility in primary aldosteronism.

Impact of Performing Nonurgent Interventional Radiology Procedures on Weekends.

Most clinical services limit weekend care to urgent or emergent situations. However, providing access to nonemergent procedures on weekends may reduce length of hospital stay and unnecessary admissions. No data are available on the impact of providing nonemergent interventional radiology (IR) procedural services on weekends. A retrospective review of nonurgent IR inpatient services on weekends over a 12-month period was performed. Using intent-to-treat analysis, 453 procedures were performed on 447 patients on 100 weekend days. Procedures included venous access (116 of 453, 25.6%), dialysis interventions (83 of 453, 18.3%), enteral access (73 of 453, 16.1%), genitourinary interventions (37 of 453, 8.2%), venous interventions (35 of 453, 7.7%), biliary interventions (33 of 453, 7.3%), percutaneous drainage (32 of 453, 7.1%), biopsy (24 of 453, 5.3%), arterial interventions (14 of 453, 3.1%), and other (3 of 453, 0.7%). Routine weekend procedural services allowed 108 of 447 (24.2%) patients to be discharged earlier than anticipated if such services were not available, resulting in 174 hospital days gained. Procedures were performed earlier than anticipated in 268 of 447 (60.0%) patients resulting in 415 days of progression of care gained over the 12-month period. For dialysis interventions, 35% (29 of 83) of patients received hemodialysis within 24 hours of intervention, and 25 patients were discharged early with 33 hospital days saved. IR procedures were performed on patients from 97% of the hospital inpatient units (22 of 23 inpatient or observation units, and 10 of 10 intensive care units) over the 12-month period. In conclusion, increased availability of nonurgent IR services on weekends can directly reduce hospital length of stay as well as improve progression of inpatients toward an early discharge.