Contralateral Suppression at Adrenal Venous Sampling Is Associated with Renal Impairment Following Adrenalectomy for Unilateral Primary Aldosteronism

Correlation of Histopathologic Subtypes of Primary Aldosteronism with Clinical Phenotypes and Postsurgical Outcomes

CONTEXT

Clinical implications of unilateral primary aldosteronism (PA) histopathology remain to be determined in various ethnic populations.

OBJECTIVE

We examined the histopathology of unilateral PA using CYP11B2 immunostaining in relation to clinical phenotypes and postsurgical outcomes.

METHODS

Patients consecutively operated for unilateral PA from 2010 to 2020 at 3 tertiary hospitals in South Korea were retrospectively enrolled. Adrenals with solitary aldosterone-producing adenomas and/or dominant aldosterone-producing nodules were classified as the classical and the others as the nonclassical groups. The classical group was subdivided into mixed or solitary group according to whether other aldosterone-producing lesions coexist or not.

RESULTS

Of the 240 cases, 124 were solitary, 86 mixed, and 30 nonclassical. Baseline serum potassium concentration was lower in the solitary group than the mixed or nonclassical group. Plasma aldosterone concentration after saline loading was the highest in the solitary group (median 31.65 ng/dL), followed by the mixed group (median 25.40 ng/dL), and the lowest in the nonclassical group (median 14.20 ng/dL). Solitary and mixed groups showed higher lateralization indices and lower contralateral indices than the nonclassical group. The contralateral index was lower in the solitary group than the mixed group. At 6 to 12 months after adrenalectomy, fewer antihypertensive medications were required for the solitary and mixed groups than the nonclassical group.

CONCLUSION

The solitary group, followed by the mixed group, was associated with more severe hyperaldosteronism and more suppressed aldosterone production from the contralateral side than the nonclassical group. Histopathologic phenotypes were related to the clinical manifestations and may suggest postoperative prognosis.

Treatment decision based on unilateral index from nonadrenocorticotropic hormone-stimulated and adrenocorticotropic hormone-stimulated adrenal vein sampling in primary aldosteronism

OBJECTIVE

Adrenal venous sampling (AVS) is recommended for identifying the subtype of primary aldosteronism before making a surgical treatment decision, but failed cannulation of one adrenal vein is common. To evaluate whether using results of one adrenal vein during AVS could accurately predict unilateral primary aldosteronism.

METHODS

A retrospective study was conducted in primary aldosteronism patients receiving bilaterally or unilaterally successful AVS. The aldosterone-cortisol ratio from the adrenal vein divided by the aldosterone-cortisol ratio from the inferior vena cava (IVC) was calculated as the AV/IVC index.

RESULTS

The study examined 455 patients with primary aldosteronism, including 347 patients with unilateral primary aldosteronism. Among them, 250 and 125 patients received non- adrenocorticotropic hormone (ACTH) and ACTH-stimulated AVS, respectively, and 80 patients received both forms of AVS. Under non-ACTH-stimulated AVS, AUC of the AV/IVC index to diagnose ipsilateral and contralateral primary aldosteronism were 0.778 and 0.924, respectively. The specificity was 100% for both, with sensitivities of 5 and 26%, respectively, when using cutoffs of 17.05 to diagnose ipsilateral primary aldosteronism and 0.15 to diagnose contralateral primary aldosteronism. When using cutoffs of 3.60 and 0.70, the specificity decreased, but if combined with CT results (ipsilateral or contralateral adrenal nodules larger than 10 mm), the specificity could be maintained at 99%, with sensitivities of 33 and 45%, respectively. Under ACTH-stimulated AVS, the AV/IVC index showed similar accuracy to diagnose ipsilateral and contralateral primary aldosteronism.

CONCLUSION

The unilateral AV/IVC index can be used to diagnose unilateral primary aldosteronism during AVS. Combining CT results can increase the accuracy further.

Factors Predicting Long-term Estimated Glomerular Filtration Rate Decrease, a Reliable Indicator of Renal Function After Adrenalectomy in Primary Aldosteronism

OBJECTIVE

The long-term decrease in estimated glomerular filtration rate (eGFR) in patients with primary aldosteronism (PA) after adrenalectomy may be influenced by multiple preoperative factors. The present study aimed to provide a systematic review and meta-analysis of these factors.

METHODS

A systematic literature search was conducted to determine eligible observational studies on the possible association between preoperative factors and postoperative long-term eGFR decrease in patients with PA using PubMed, Web of Science, Embase, and Cochrane Library databases.

RESULTS

A total of 8 relevant studies with 1159 patients were included. Old age (odds ratio [OR] = 1.05, 95% CI: 1.02-1.09, P = .001), high systolic blood pressure (OR = 1.05, 95% CI: 1.01-1.09, P = .01), baseline hypokalemia (OR = 0.08, 95% CI: 0.02-0.30, P < .001), and low eGFR (OR = 0.92, 95% CI: 0.87-0.97, P = .001) presented a strong association with long-term eGFR decrease after adrenalectomy.

CONCLUSION

We provide evidence that old age, high systolic blood pressure, baseline hypokalemia, and low eGFR are associated with an increased risk of postoperative long-term eGFR decrease in patients with PA postoperatively. More attention should be given to the above factors for the timely prevention and management of renal impairment.

Prognostic value of contralateral suppression on kidney function after surgery in patients with primary aldosteronism

BACKGROUND AND OBJECTIVE

Adrenalectomy for primary aldosteronism (PA) has been associated with decreased kidney function after surgery. It has been proposed that elimination of excess aldosterone unmasks an underlying failure of the kidney function. Contralateral suppression (CLS) is considered a marker of aldosterone excess and disease severity, and the purpose of this study was to assess the hypothesis that CLS would predict change in kidney function after adrenalectomy in patients with PA.

DESIGN AND PATIENTS

Patients with PA referred for adrenal venous sampling (AVS) between May 2011 and August 2021 and who were subsequently offered surgical or medical treatment were eligible for the current study.

RESULTS

A total of 138 patients were included and after AVS 85/138 (61.6%) underwent adrenalectomy while 53/138 (38.4%) were treated with MR-antagonists. In surgically treated patients the estimated glomerular filtration rate (eGFR) was reduced by 11.5 (SD: 18.5) compared to a reduction of 5.9 (SD: 11.5) in medically treated patients (p = .04). Among surgically treated patients, 59/85 (69.4%) were classified as having CLS. After adrenalectomy, patients with CLS had a mean reduction in eGFR of 17.5 (SD: 17.6) compared to an increase of 1.8 (SD: 12.8) in patients without CLS (p < .001). The association between CLS and change in kidney function remained unchanged in multivariate analysis. Post-surgery, 16/59 (27.1%) patients with CLS developed hyperkalemia compared to 2/26 (7.7%) in patients without CLS (p = .04).

CONCLUSION

This retrospective study found that CLS was a strong and independent predictor of a marked reduction of eGFR and an increased risk of hyperkalemia after adrenalectomy in patients with PA.

Prognostic value of contralateral suppression for remission after surgery in patients with primary aldosteronism

OBJECTIVE

Primary aldosteronism (PA) is the most common cause of endocrine hypertension and adrenalectomy is the firstline treatment for unilateral PA. Suppression of aldosterone secretion of the nondominant adrenal gland at adrenal venous sampling (AVS), that is, contralateral suppression (CLS) has been suggested as a marker of disease severity. However, whether factors such as CLS, age, gender or comorbidities are associated with remission after surgery is controversial. The objective of this study is to investigate the prognostic value of CLS, age, gender, aldosterone-to-renin ratio, antihypertensives and comorbidities for clinical and biochemical remission following unilateral adrenalectomy in patients with PA.

DESIGN AND PATIENTS

A retrospective study of patients with PA referred for AVS at Rigshospitalet from May 2011 to September 2020, who subsequently underwent adrenalectomy. Clinical remission was defined according to the PA surgical outcome criteria, whereas complete biochemical remission was defined as normalization of hypokalaemia without potassium substitution.

RESULTS

Eighty-four patients were available for analysis of primary outcome. Among patients with CLS, 28/58 (48.3%) obtained complete clinical remission after surgery compared with 10/26 (38.5%) without CLS (p = .40). Complete biochemical remission was obtained in 55/58 (94.8%) of patients with CLS compared with 25/28 (89.3%) without CLS (p = .44). Female gender and lower number of antihypertensives at baseline were associated with higher odds for complete clinical remission, whereas none of the investigated variables were associated with biochemical remission.

CONCLUSION

CLS was not significantly associated with complete clinical or biochemical remission in this cohort. Our results confirmed that female gender and lower number of antihypertensives were predictors of clinical remission.