Contralateral suppression in adrenal venous sampling predicts clinical and biochemical outcome in primary aldosteronism

CONTEXT

The role for hormone parameters at adrenal venous sampling (AVS) in predicting clinical and biochemical outcome remains controversial.

OBJECTIVE

To investigate the impact of hormone parameters at AVS under cosyntropin stimulation on lateralization and on complete biochemical and clinical outcome.

METHODS

We retrospectively evaluated 150 sequential AVS under cosyntropin infusion. Bilateral successful cannulation rate was 83.3% (n = 140), 47.9% bilateral and 52.1% unilateral. The lateralization index (LI), aldosterone/cortisol ratio (A/C) in the dominant adrenal vein (AV), relative aldosterone secretion index (RASI = A/C in AV divided by A/C in inferior vena cava) were assessed. The contralateral suppression (CS) percentage was defined by (1 - nondominant RASI) *100.

RESULTS

A nondominant RASI <0.5 (CS >50%) had 86.84% sensitivity and 92.96% specificity to predict contralateral lateralization. An A/C ratio in dominant AV >5.9 (74.67% sensitivity and 80% specificity) and dominant RASI >4.7 (35.21% sensitivity and 88.06% specificity) had a worst performance to predict ipsilateral lateralization. Complete biochemical and clinical cure were significantly more frequent in the patients with CS >50% [98.41% vs. 42.86% (p < 0.001) and 41.94% vs. 0% (p < 0.001)]. CS correlated with high aldosterone at diagnosis (p < 0.001) and low postoperative aldosterone levels at 1 month (p = 0.019). Postoperative biochemical hypoaldosteronism was more frequent in patients with CS >50% (70% vs. 16.67%, p = 0.014). In multivariable analysis, a CS >50% was associated with complete biochemical cure (OR 125, 95%CI 11.904-5,000; p = 0.001) and hypertension remission (OR 12.19, 95%CI 2.074-250; p = 0.023).

CONCLUSION

A CS >50% was an independent predictor of complete clinical and biochemical cure. Moreover, it can predict unilateral PA and postoperative biochemical hypoaldosteronism. Our findings underscore the usefulness of CS for clinical decision-making.

Intraindividual variability of serum aldosterone and its implication for primary aldosteronism screening

CONTEXT

Primary aldosteronism (PA) screening relies on an elevated aldosterone to renin ratio with a minimum aldosterone level, which varies from 10 to 15 ng/dL (277 to 415.5 pmol/L) using immunoassay.

AIM

To evaluate intraindividual coefficient of variation (CV) of aldosterone and aldosterone to direct renin concentration ratio (A/DRC) and its impact on PA screening.

METHODS

A total of 671 aldosterone and DRC measurements were performed by the same chemiluminescence assays in a large cohort of 216 patients with confirmed PA and at least two screenings.

RESULTS

The median intraindividual CV of aldosterone and A/DRC was 26.8% and 26.7%. Almost 40% of the patients had at least one aldosterone level <15 ng/dL, 19.9% had at least two aldosterone levels <15 ng/dL and 16.2% had mean aldosterone levels <15 ng/dL. A lower cut-off of 10 ng/dL was associated with false negative rates for PA screening of 14.3% for a single aldosterone measurement, 4.6% for two aldosterone measurements and only 2.3% for mean aldosterone levels. Considering the minimum aldosterone, true positive rate of aldosterone thresholds was 85.7% for 10 ng/dL and 61.6% for 15 ng/dL. An A/DRC >2 ng/dL/µIU/mL had a true positive rate for PA diagnosis of 94.4% and 98.4% when based on one or two assessments, respectively. CV of aldosterone and A/DRC were not affected by sex, use of interfering anti-hypertensive medications, PA lateralization, hypokalemia, age and number of hormone measurements.

CONCLUSION

Aldosterone concentrations had a high CV in PA patients, which results in an elevated rate of false negative test in a single screening for PA. Therefore, PA screening should be based in at least two screenings with concomitant aldosterone and renin measurements.

Phosphodiesterase 2A and 3B variants are associated with primary aldosteronism

Familial primary aldosteronism (PA) is rare and mostly diagnosed in early-onset hypertension (HT). However, 'sporadic' bilateral adrenal hyperplasia (BAH) is the most frequent cause of PA and remains without genetic etiology in most cases. Our aim was to investigate new genetic defects associated with BAH and PA. We performed whole-exome sequencing (paired blood and adrenal tissue) in six patients with PA caused by BAH that underwent unilateral adrenalectomy. Additionally, we conducted functional studies in adrenal hyperplastic tissue and transfected cells to confirm the pathogenicity of the identified genetic variants. Rare germline variants in phosphodiesterase 2A (PDE2A) and 3B (PDE3B) genes were identified in three patients. The PDE2A heterozygous variant (p.Ile629Val) was identified in a patient with BAH and early-onset HT at 13 years of age. Two PDE3B heterozygous variants (p.Arg217Gln and p.Gly392Val) were identified in patients with BAH and HT diagnosed at 18 and 33 years of age, respectively. A strong PDE2A staining was found in all cases of BAH in zona glomerulosa and/or micronodules (that were also positive for CYP11B2). PKA activity in frozen tissue was significantly higher in BAH from patients harboring PDE2A and PDE3B variants. PDE2A and PDE3B variants significantly reduced protein expression in mutant transfected cells compared to WT. Interestingly, PDE2A and PDE3B variants increased SGK1 and SCNN1G/ENaCg at mRNA or protein levels. In conclusion, PDE2A and PDE3B variants were associated with PA caused by BAH. These novel genetic findings expand the spectrum of genetic etiologies of PA.

SUN-195 Bilateral Aldosterone-Producing Adenomas: A New Subtype of Bilateral Primary Aldosteronism?

Background: Primary aldosteronism (PA) is the most common cause of endocrine hypertension (HT). PA subtypes include aldosterone-producing adenomas (APA) and bilateral adrenal hyperplasia. To date, few PA patients with bilateral adenomas have been reported, but only one case was well characterized by anatomopathological analysis and clinical outcome after adrenal sparing surgery (1).

Clinical case: A 53-year-old woman was referred to investigate resistant HT and hypokalemia. (3.0 mEq/L). PA screening revealed aldosterone (A) of 37.9 ng/dL, renin (R) < 1.6 (4.4-46.1 mUI/L), A/R ratio of 24.8. Confirmatory testing confirmed PA diagnosis: seated saline infusion test (A= 83.3 ng/dL) and intravenous furosemide test (R= 3.1 mUI/L; positive test <13 mUI/L). Hypercortisolism investigation revealed a non-suppressible cortisol after an overnight 1 mg low-dose dexamethasone suppression [cortisol (C)= 2.9 μg/dL and dexamethasone= 701 (˃130 ng/dL)], and normal urinary free cortisol, midnight salivary cortisol, plasma DHEAS and ACTH levels. Computed tomography demonstrated bilateral adrenal nodules without adrenal thickening: 3.5 cm right nodule (pre-contrast density of 7UH density; absolute wash-out of 71%) and 2.5 cm left nodule (pre-contrast density of 8UH density; absolute wash-out of 78%). Sequential adrenal venous (AV) sampling (AVS) under continuous cosyntropin infusion showed a lateralization index of 3.4 (bilateral disease <4). Then, the patient underwent right adrenalectomy and left nodulectomy. In the postoperative period, she presented normalization of K⁺ levels and complete HT remission. She remained under hydrocortisone replacement for 2 months. After 2 months, biochemical evaluation revealed normal basal cortisol levels (13.3 µg/dL) and biochemical cure of PA (A= 3.1 ng/dL and R= 15.3 mUI/L). Currently, she doesn’t have symptoms of adrenal insufficiency after discontinuation of hydrocortisone. Anatomopathological analysis showed bilateral adenomas (Weiss score of 0) in both sides without adjacent hyperplasia. CYP11B2 immunohistochemistry displayed a strong staining in 50% of cells in the right adenoma and in 30% of cells in the left adenoma. Few aldosterone-producing cell clusters (APCC) were identified in the right zona glomerulosa, which is a frequent finding in normal adrenals.

Conclusion: We herein described a very rare case of PA caused by bilateral-producing adenomas, confirmed by AVS and CYP11B2 staining after adrenal sparing surgery.

Functional and metabolic imaging in transthoracic biopsies guided by computed tomography

OBJECTIVES

CT-guided biopsy of indeterminate lung lesions sometimes provides insufficient histological results due to tumor necrosis. Functional and metabolic methods such as DWI-MR and PET-CT may help by directing sample collection to a lesion area of greater biological representativeness. The objective is to evaluate the histopathological results based on findings on ADC and SUV levels in lung lesions suspected for primary cancer.

METHODS

Tissue samples were evaluated after undergoing biopsies guided by either DWI-MR or PET-CT findings. In each patient, sample collection from two lesion areas was guided by local ADC and SUV. Values were used to define areas of low vs. high suspicion for cancer.

RESULTS

Patients who underwent DWI-MR had median lesion size of 78.0 mm. Areas of higher suspicion (HSA) had a median ADC of 1.1 × 10^-3 mm²/s, while areas of lower suspicion (LSA) had median ADC of 1.8 × 10^-3 mm²/s (p = 0.0001). All HSA samples and 71.43% of LSA samples were positive for cancer (p = 0.0184). Patients who performed PET-CT had median lesion size of 61.0 mm. Median SUV was 7.1 for HSA and 3.9 for LSA (p = 0.0002). Positivity for cancer was observed in 76.9% of samples for both HSA and LSA (p = 0.0522).

CONCLUSION

Use of DWI-MR and PET-CT showed that tumors are functional and metabolically heterogeneous and that this heterogeneity has implications for histopathological diagnosis.

KEY POINTS

• Lung cancer is heterogeneous regarding functional and metabolic imaging. • Tumor heterogeneity may have implications in histopathological diagnosis. • Intralesional lower levels of ADC target highly suspected areas with a significant improvement in lung cancer diagnosis.

KCNJ5 Somatic Mutation Is a Predictor of Hypertension Remission After Adrenalectomy for Unilateral Primary Aldosteronism

CONTEXT

Primary aldosteronism (PA) is the most common cause of endocrine hypertension (HT). HT remission (defined as blood pressure <140/90 mm Hg without antihypertensive drugs) has been reported in approximately 50% of patients with unilateral PA after adrenalectomy. HT duration and severity are predictors of blood pressure response, but the prognostic role of somatic KCNJ5 mutations is unclear.

OBJECTIVE

To determine clinical and molecular features associated with HT remission after adrenalectomy in patients with unilateral PA.

METHODS

We retrospectively evaluated 100 patients with PA (60 women; median age at diagnosis 48 years with a median follow-up of 26 months). Anatomopathological analysis revealed 90 aldosterone-producing adenomas, 1 carcinoma, and 9 unilateral adrenal hyperplasias. All patients had biochemical cure after unilateral adrenalectomy. KCNJ5 gene was sequenced in 76 cases.

RESULTS

KCNJ5 mutations were identified in 33 of 76 (43.4%) tumors: p.Gly151Arg (n = 17), p.Leu168Arg (n = 15), and p.Glu145Gln (n = 1). HT remission was reported in 37 of 100 (37%) patients. Among patients with HT remission, 73% were women (P = 0.04), 48.6% used more than three antihypertensive medications (P = 0.0001), and 64.9% had HT duration <10 years (P = 0.0015) compared with those without HT remission. Somatic KCNJ5 mutations were associated with female sex (P = 0.004), larger nodules (P = 0.001), and HT remission (P = 0.0001). In multivariate analysis, only a somatic KCNJ5 mutation was an independent predictor of HT remission after adrenalectomy (P = 0.004).

CONCLUSION

The presence of a KCNJ5 somatic mutation is an independent predictor of HT remission after unilateral adrenalectomy in patients with unilateral PA.

Long-term outcomes of transmesenteric portal vein recanalization for the treatment of chronic portal vein thrombosis after pediatric liver transplantation

Portal vein thrombosis (PVT) may occur at any time following liver transplantation. We describe our experience with portal vein recanalization in cases of thrombosis after liver transplantation. Twenty-eight children (5%) out of 566 liver transplant recipients underwent portal vein recanalization using a transmesenteric approach. All children received left hepatic segments, developed PVT, and had symptoms or signs of portal hypertension. Portal vein recanalization was performed via the transmesenteric route in all cases. Twenty-two (78.6%) patients underwent successful recanalization and stent placement. They received oral anticoagulants after the procedure, and clinical symptoms subsided. Symptoms recurred due to portal vein restenosis/thrombosis in seven patients. On an intention-to-treat basis, the success rate of the proposed treatment was 60.7%. Only 17 out of 28 children with posttransplant chronic PVT retained stent patency (primary + assisted) at the end of the study period. In cases of portal vein obstruction, the transmesenteric approach via minilaparotomy is technically feasible with good clinical and hemodynamic results. It is an alternative procedure to reestablish the portal flow to the liver graft that can be performed in selected cases and a therapeutic addition to other treatment strategies currently used to treat chronic PVT.