Comparison of adrenal vein sampling and computed tomography in the differentiation of primary aldosteronism

Determination of the etiology of primary aldosteronism remains a diagnostic challenge. The most common types of primary aldosteronism are bilateral adrenal hyperplasia (BAH), aldosterone-producing adenomas (APA), and primary adrenal hyperplasia. Computed tomography (CT) and adrenal vein sampling (AVS) are the primary modalities used to differentiate these subtypes. The purpose of this study was to compare AVS and CT imaging of the adrenal glands in patients with hyperaldosteronism in whom CT imaging was normal or in whom focal unilateral or bilateral adrenal abnormalities were detected. The diagnosis of primary aldosteronism was made in 62 patients based on an elevated plasma aldosterone to PRA ratio and an elevated urinary aldosterone excretion rate. Thirty-eight patients had CT imaging and successful bilateral adrenal vein sampling and were included in the final analysis. AVS was considered the gold standard in determining the specific subtype of primary aldosteronism. There were 15 patients with APA, 21 patients with BAH, and 2 patients with primary adrenal hyperplasia. Plasma aldosterone was significantly higher in patients with APA (46.3 +/- 8.5 ng/dL; 1284 +/- 235 pmol/L) than in those with BAH (29.3 +/- 2.4 ng/dL; 813 +/- 11 pmol/L; P < 0.05). Plasma potassium was significantly lower in patients with APA (3.1 +/- 0.1 mmol/L) than in patients with BAH (3.5 +/- 0.1 mmol/L; P < 0.02). There was considerable overlap in the other biochemical indices (e.g. PRA and urinary aldosterone) in patients with the different subtypes. In patients with APA proven by AVS, eight had concordant findings with CT imaging, four had discordant findings, and three had normal CT imaging. In patients with BAH proven by AVS, four had concordant findings with CT imaging, eight had discordant findings, and nine had normal CT imaging. Compared with AVS, CT imaging was either inaccurate or provided no additional information in 68% of the patients with primary aldosteronism. We conclude that adrenal CT imaging is not a reliable method to differentiate primary aldosteronism. Adrenal vein sampling is essential to establish the correct diagnosis of primary aldosteronism.     

Diagnostic accuracy of adrenal venous sampling in comparison with other parameters in primary aldosteronism

This retrospective study was aimed 1) to compare the difference of the findings between adrenal CT scan and adrenal venous sampling (AVS) in 35 cases with definite primary aldosteronism (PA) for assessment of the diagnostic efficacy of PA subgroup (unilateral and bilateral adrenal hypersecretion: UAH and BAH), and 2) to determine the clinical and biochemical parameters as potential predictors for PA subgroup. There were significant discordant results based on AVS and CT scan in subgrouping PA; 9 of 17 BAH patients (53%) had unilateral lesion on CT scan, while 4 of 18 UAH patients (22%) had no apparent or bilateral lesions on CT scan. Among three diagnostic criteria, absolute values of plasma aldosterone concentration (PAC) in both adrenal veins, lateralized and contralateral ratios of aldosterone/cortisol after ACTH stimulation during AVS to determine the laterality, none of them showed 100% diagnostic accuracy if applied alone. Among several clinical and biochemical parameters, hypokalemia (<3.4 mEq/l), younger age (<52 y) and poor response of PAC (<1.45) after furosemide-upright posture, proved to be significant predictors for UAH, with higher specificities (100%, 88%, 94%, respectively). Therefore, despite AVS as a gold standard method to determine the laterality of aldosterone hypersecretion in PA, our study shows that no single criterion could provide definite diagnostic value for its laterality by AVS. It is also suggested that most PA patients, if not all, with a distinct unilateral adrenal lesion on CT accompanied by hypokalemia, younger age and poor aldosterone response to renin stimulation, could undergo adrenalectomy without prior AVS.     

Roles of clinical criteria, computed tomography scan, and adrenal vein sampling in differential diagnosis of primary aldosteronism subtypes

CONTEXT: In patients with primary aldosteronism (PA), it is fundamental to distinguish between subtypes that benefit from different therapies. Computed tomography (CT) scans lack sensitivity and specificity and must be followed by adrenal venous sampling (AVS). Because AVS is not widely available, a list of clinical criteria that indicate the presence of an aldosterone-producing adenoma (APA) has been suggested. OBJECTIVE AND DESIGN: The objective of the study was to test the sensitivity and specificity of the last generation CT scans, test prospectively the usefulness of clinical criteria in the diagnosis of APA, and develop a flow chart to be used when AVS is not easily available. SETTING: Hypertensive patients referred to our hypertension unit were included in our study. PATIENTS: Seventy-one patients with confirmed PA participated in our study. Intervention: All patients had a CT scan and underwent AVS. MAIN OUTCOME MEASURE: Final diagnosis of APA was the main measure. RESULTS: A total of 44 and 56% of patients were diagnosed as having an APA and a bilateral adrenal hyperplasia (BAH), respectively. Twenty percent of patients with PA displayed hypokalemia. CT scans displayed a sensitivity of 0.87 and a specificity of 0.71. The posture test displayed a lower sensitivity and specificity (0.64 and 0.70, respectively). The distribution grades of hypertension were not significantly different between APA and BAH. Biochemical criteria of high probability of APA displayed a sensitivity of 0.32 and a specificity of 0.95. CONCLUSIONS: This study underlines the central role of AVS in the subtype diagnosis of PA. The use of the clinical criteria to distinguish between APA and BAH did not display a satisfactory diagnostic power.     

肾上腺静脉采血在原发性醛固酮增多症分型诊断中的应用

目的探讨肾上腺静脉采血（AVS）检查在原发性醛固酮增多症（原醛症）分型诊断中的应用价值。方法收集瑞金医院近4年来39例临床确诊的原醛症患者[23例特发性醛固酮增多症（特醛症），16例醛固酮瘤]，经肾上腺静脉插管检查，取双侧肾上腺静脉以及肾静脉水平下的下腔静脉血液，测各点醛固酮和皮质醇水平，并将结果与影像学检查、体位激发试验（PST）及术后病理结果进行比较。结果（1）23例特醛症患者体位激发后血醛固酮较基础值均升高；16例醛固酮瘤患者血醛固酮升高者占56．3％（9／16）；（2）特醛症患者肾上腺B超检查符合率为69．6％（16／23），醛固酮瘤患者为56．3％（9／16）；肾上腺CT检查特醛症患者符合率为73．9％（17／23），醛固酮瘤患者为81．3％（13／16）；（3）AVS检查以两侧醛固酮之比作为判定标准时符合率为71．8％，以醛固酮与皮质醇之比为判定标准则达到100％。醛固酮瘤患者生化异常程度较特醛症患者明显。PST在特醛症及醛固酮瘤中有部分重叠；体位激发后血醛固酮升高者不能排除醛固酮瘤，而血醛固酮下降者可诊断为醛固酮瘤。结论单纯依赖影像学检查对于原醛症患者进行分型诊断易发生误诊。AVS检查的准确性高，对于影像学检查未能发现明显占位性病变者须进行该检查以明确诊断；对于AVS结果，用两侧醛固酮与皮质醇的比值之比分析较单纯比较两侧醛固酮之比更为可靠。     

New diagnostic procedure for primary aldosteronism: adrenal venous sampling under adrenocorticotropic hormone and angiotensin II receptor blocker--application to a case of bilateral multiple adrenal microadenomas.

Formerly, the incidence of primary aldosteronism (PA) among patients with hypertension was believed to be less than 1%. However, recent studies have suggested a much higher incidence of 6.59%-14.4% among such patients. These findings suggest that many cases of PA caused by small aldosterone-producing adenoma (APA) or idiopathic hyperaldosteronism (IHA) have not been properly diagnosed. To make a more accurate diagnosis in such cases, we developed a new diagnostic procedure for localization of PA, namely, adrenal venous sampling under continuous infusion of adrenocorticotropic hormone (ACTH) and administration of angiotensin II receptor blocker (AVS with ACTH and ARB). Here, we confirm the efficacy of this procedure in the case of a 37-year-old male suspected of having PA. The anticipated diagnosis of PA was based on the presence of hypokalemia, low plasma renin activity (PRA), elevated plasma aldosterone concentration (PAC) and left adrenal mass. However, AVS with ACTH and ARB revealed the presence of bilateral multiple adrenal microadenomas. In the new AVS method, neither ACTH nor the renin-angiotensin system (RAS) exert any influence on the plasma aldosterone level, and a more accurate aldosterone secretary state and a more accurate assessment of the aldosterone secretion of both adrenal glands can be recognized than by conventional AVS. Use of this new method should enable identification of additional cases of APA among patients diagnosed with essential hypertension.     

Clinical characteristics of aldosterone-producing microadenoma, macroadenoma, and idiopathic hyperaldosteronism in 93 patients with primary aldosteronism.

Primary aldosteronism (PA) due to aldosterone-producing adenoma (APA) is a form of surgically curable secondary hypertension, and distinguishing APA from idiopathic hyperaldosteronism (IHA) is important for treatment. We made a differential diagnosis between APA and IHA using imaging tests such as adrenal CT and MRI as well as adrenal venous sampling (AVS) in all 93 cases of PA presenting at our institutions over the last decade. We identified 27 patients with aldosterone-producing microadenoma (APmicroA), all of whom could be diagnosed by AVS but not by the imaging tests. Then, we compared the clinical and roent-genological findings of these 27 patients with those of 42 patients with aldosterone-producing macroadenoma (APmacroA) and of 24 patients with IHA. Using surgically removed adrenal tissues, histopathological examinations and immunohistochemical analyses of steroidogenic enzymes were conducted. The findings for APmicroA were similar to those for APmacroA, except with respect to the diameter of the adrenal adenomas. Endocrinological and roentgenological findings for APmicroA were similar to those for IHA, but not to those for APmacroA. The rate of cure of hypertension was much greater in patients with APmicroA than in patients with APmacroA after the unilateral adrenalectomy (odds ratio, 4.0; p=0.028). In conclusion, it is important to accurately diagnose APmicroA, in which the laterality of the hyperproduction of aldosterone is only detectable by AVS, and to treat these patients by unilateral adrenalectomy in order to avoid long-term medical treatment and prevent hypertensive vascular complications.     

Dynamic testing with high-dose adrenocorticotrophic hormone does not improve lateralization of aldosterone oversecretion in primary aldosteronism patients

OBJECTIVE: Diagnosing aldosterone-producing adenoma (APA) involves a demonstration of the lateralization of aldosterone oversecretion because adrenal incidentalomas are common in hypertensive individuals and many small-sized APA escape identification with available imaging techniques. However, because of the pulsatile pattern of aldosterone secretion this can be a difficult undertaking. Stimulation of aldosterone secretion before adrenal vein sampling (AVS) can overcome this difficulty, but anecdotal data exist. We, therefore, prospectively investigated the usefulness of AVS with dynamic testing in primary aldosteronism (PA) patients. METHODS: We enrolled 24 consecutive consenting patients with a biochemical diagnosis of PA from a tertiary referral centre to measure the effects of adrenocorticotrophic hormone (ACTH) on selectivity, the lateralization of aldosterone secretion to the APA side, and adverse effects. After correcting the hypokalemia we performed bilateral AVS. After 3 h supine resting, blood was simultaneously obtained from both sides. A high-dose ACTH (250 mug intravenous) bolus was then administered and AVS was repeated after 30 min. RESULTS: AVS was bilaterally selective in 88% of patients; no adverse effects occurred. Of the 21 patients with bilaterally selective AVS, three had idiopathic hyperaldosteronism and 18 an APA that was surgically removed in 12 with an ensuing fall in blood pressure at follow-up. After ACTH patients showed a significant increase (P = 0.007) of aldosterone from contralateral adrenal vein blood, but not from the APA gland. Therefore, lateralization of aldosterone secretion on the APA side did not improve. CONCLUSION: AVS is safe and accurate for identifying APA. However, at a statistical power of 99%, these results do not support the usefulness of high-dose ACTH testing to improve the diagnostic accuracy of AVS.     

Localization of aldosterone-producing adrenocortical adenomas: significance of adrenal venous sampling.

Accurate localization of aldosterone-producing adenoma (APA) is essential for the treatment of primary aldosteronism (PA). In order to confirm the clinical usefulness of adrenal venous sampling (AVS), we retrospectively studied 87 cases of PA in whom AVS was conducted. We collected right and left adrenal venous effluents simultaneously before and after adrenocorticotropic hormone (ACTH) stimulation for measurements of aldosterone concentration (A) and cortisol concentration (C). Based on AVS results, we judged 66 cases as having unilateral aldosterone hypersecretion and the remaining 21 cases as having no apparent laterality. Of the above 66 subjects, 61 underwent laparoscopic removal of the adrenal gland through a retroperitoneal approach. The presence of APA was histopathologically confirmed, and blood pressure decreased significantly with normalization of plasma aldosterone concentration (PAC) in all cases. The receiver operator characteristics (ROC) curve analysis between the operated and no-apparent-laterality groups revealed that the ratio of A/C on the higher side to A/C on the lower side (A/C ratio) after ACTH stimulation is a useful index, with a cutoff value of 2.6, a sensitivity of 0.98 and a specificity of 1.0. The ROC curve analysis between the APA side and contralateral side within the operated patients revealed that the cutoff value of A was 1,340 ng/dL, with a sensitivity of 0.92 and a specificity of 1.00. Our results indicate the usefulness of simultaneous AVS and ACTH stimulation for localizing APA.     

探讨促肾上腺皮质激素兴奋在肾上腺静脉取血中的应用价值

目的:探讨促肾上腺皮质激素(ACTH)兴奋在肾上腺静脉取血(AVS)中的应用价值。方法:纳入完成常规AVS和ACTH兴奋的AVS,且至少有一种AVS双侧肾上腺静脉插管成功的原发性醛固酮增多症(原醛症)患者。计算选择指数(SI)、优势侧指数(LI),比较ACTH兴奋与否对插管成功率及优势侧判断的影响。结果:共纳入73名原...     

Surgical versus medical management of patients with primary hyperaldosteronism and indeterminate adrenal vein sampling: A 10-year experience of the Cleveland Clinic

In patients with primary hyperaldosteronism (PA), adrenal vein sampling (AVS) can identify patients suitable for unilateral adrenalectomy. However, in AVS with an indeterminate aldosterone-to-cortisol lateralization (ACL) ratio of 3.0–4.0, clinical guidance is unclear. The authors screened all patients undergoing AVS at the Cleveland Clinic from October 2010 to January 2021 and identified 18 patients with indeterminate ACL results. Ten underwent adrenalectomy and eight continued medical management. The surgical group was younger (58.5 vs. 68 years, p = .17), and more likely to have a unilateral imaging adrenal abnormality (90% vs. 38%, p = .043) and a lower contralateral suppression index (0.63 vs. 1.1, p = .14). Post-treatment, the surgical group had a significant reduction in diastolic blood pressure (–5.5 mmHg, p = .043) and aldosterone (4.40 vs. 35.80 ng/mL, p = .035) and required fewer anti-hypertensive medications (2 vs. 3, p = .015). These findings may support the benefit of adrenalectomy in a select group of patients with indeterminate ACL.     

Primary aldosteronism due to unilateral adrenal hyperplasia: report of two cases and review of the literature

Unilateral adrenal hyperplasia (UAH) is a rare, surgically correctable subset of primary aldosteronism (PA), which shows similar endocrine features to aldosterone-producing adenoma (APA). We report here two Japanese patients with UAH. Case 1 was a 62-year-old man with a four-year history of hypertension. Hypokalemia and suppressed plasma renin activity (PRA) with elevated plasma aldosterone concentration (PAC) were observed, while no adrenal nodules were identified by abdominal computed tomographic (CT) scan. Adrenal scintigraphy did not reveal definite localization. The selective adrenal-vein sampling for determinations of PAC showed an over-functioning left adrenal gland, and a left adrenalectomy was performed. Diffuse micronodular adrenocortical hyperplasia was observed. Case 2 was a 61-year-old man with a six-year history of hypertension. At the first visit to our hospital, hypokalemia and suppressed PRA with elevated PAC were observed. An abdominal CT scan showed a left adrenal mass 1.5 cm in diameter, while adrenal scintigraphy did not reveal definite laterality. A left adrenalectomy was performed, and three macronodules and diffuse micronodular adrenocortical hyperplasia were observed. Hypokalemia, hypertension and endocrine data became normal, and both patients have been well with no signs of recurrence for eight years (case 1) and seven months (case 2) after surgery. Clinical characteristics and endocrine features of UAH are also reviewed.     

A case of primary aldosteronism due to unilateral adrenal hyperplasia.

The case of a patient with primary aldosteronism due to unilateral adrenal hyperplasia (UAH) is reported. A 43-year-old man with an 8-year history of hypertension presented at our institution with hypokalemia, increased plasma aldosterone concentration (PAC), and suppressed plasma renin activity (PRA). An abdominal CT scan showed almost normal adrenal glands with slight enlargement in the left gland. 131I-Norcholesterol adrenal scintigraphy under dexamethasone suppression showed bilaterally decreased uptake. To rule out idiopathic hyperaldosteronism, an adrenal vein sampling before and after ACTH stimulation was performed and a left-sided lateralization of PAC was observed. A left adrenalectomy was performed, and the patient had a good clinical and biochemical response. Micronodular hyperplasia was discovered in the adrenal gland histologically, and in the immunohistochemical analysis, positive staining for 3beta-hydroxysteroid dehydrogenase in micronodular lesions confirmed the diagnosis of UAH. Although UAH is a rare subset of primary aldosteronism, it is surgically correctable as a unilateral autonomous aldosterone-producing lesion. Careful investigations, including bilateral adrenal vein sampling, should be performed for the diagnosis.     

原发性醛固酮增多症的分型诊断

目的 探讨用于原发性醛固酮增多症(原醛症)分型诊断检查方法的价值.方法 收集本院近7年来57例临床确诊的原醛症患者[醛固酮瘤22例,特发性醛固酮增多症(特醛症)26例,原发性肾上腺增生9例],检测患者的血电解质、血浆肾素活性及血、尿醛固酮,将结果与19例原发性高血压患者对照.再通过肾上腺CT、体位激发试验及肾上腺静脉采血检查对原醛症患者分型并随访.结果 (1)醛固酮瘤患者血压及血、尿醛固酮较特醛症患者高,血钾及血浆肾素活性则低,而原发性肾上腺增生患者临床及生化改变介于两者之间.肾上腺CT检查在原醛症分型诊断中的符合率为醛固酮瘤86.4%,特醛症73.1%,原发性肾上腺增生22.2%;肾上腺静脉采血检查以两侧醛固酮之比作为判定标准时符合率为86.4%、80.8%和77.8%,以醛固酮与皮质醇之比为判定标准则符合率分别为95.5%、92.3%及100.0%.(2)醛固酮瘤及原发性肾上腺增生患者术后随访血醛固酮均下降,血压恢复正常者分别为22.7%及44.9%,血钾恢复正常者为83.3%及100.0%,而特醛症患者随访中各项测值无明显变化,另有33.3%诊断时血钾正常的患者随访中出现低血钾.结论 原醛症的分型诊断需依靠多种检查手段综合分析,单纯依赖影像学检查或体位激发试验并不可靠,肾上腺静脉采血检查可作为影像学检查的补充,用两侧醛固酮与皮质醇的比值分析较单纯比较两侧醛固酮之比更为可靠;醛固酮瘤及原发性肾上腺增生患者术后临床及生化测值均得以明显改善,而特醛症患者随访中无明显变化.     

Unique cases of unilateral hyperaldosteronemia due to multiple adrenocortical micronodules, which can only be detected by selective adrenal venous sampling

Primary aldosteronism is classified as aldosterone-producing adenoma (APA), idiopathic hyperaldosteronism (IHA), unilateral adrenal hyperplasia (UAH), primary adrenal hyperplasia (PAH), adrenal cancer, and glucocorticoid-remediable aldosteronism. We describe here 4 cases of primary aldosteronism due to unilateral hyperaldosteronemia, demonstrating unique histopathologic findings, such as unilateral multiple adrenocortical micronodules in the affected adrenals. Thirty-three patients with primary aldosteronism were consecutively admitted; 27 of them were treated by unilateral adrenalectomy. Four of them also had unilateral adrenal hypersecretion of aldosterone by selective adrenal venous sampling and adrenocortical multiple micronodules without an adenoma. These patients had hyporeninemic hyperaldosteronism with normokalemic hypertension. In these patients, furosemide plus upright test failed to increase plasma renin activity (PRA); the ratio of plasma aldosterone concentration (PAC) to PRA at 90 minutes after captopril administration was similar to that in patients with IHA and APA. Aldosterone concentrations were increased in each unilateral adrenal vein, and poorly encapsulated multiple adrenocortical micronodules from 2 to 3 mm in diameter were microscopically detected in the resected adrenal glands. Immunohistochemical analysis of steroidogenic enzymes, including cholesterol side chain cleavage, 3beta-hydroxysteroid dehydrogenase, 21-hydroxylase, 17alpha-hydroxylase, and 11beta-hydroxylase, indicated that the cortical cells within these micronodules were active in aldosterone production, while the non-nodular zona glomerulosa cells were inactive. We conclude that the clinical and pathologic characteristics of our 4 cases with unilateral multiple adrenocortical micronodules (UMN) are distinct from those of APA, IHA, UAH, and PAH. Furthermore, unilateral hyperaldosteronemia induced by UMN may be frequently misdiagnosed, because standard imaging tests, which cannot always detect tiny abnormalities of adrenals, showed "normal adrenal glands" in these patients. Thus, primary aldosteronism due to UMN should be carefully examined for differential diagnosis of each form of hyperaldosteronemia.     

A prospective study of the prevalence of primary aldosteronism in 1,125 hypertensive patients.

OBJECTIVES: We prospectively investigated the prevalence of curable forms of primary aldosteronism (PA) in newly diagnosed hypertensive patients. BACKGROUND: The prevalence of curable forms of PA is currently unknown, although retrospective data suggest that it is not as low as commonly perceived. METHODS: Consecutive hypertensive patients referred to 14 hypertension centers underwent a diagnostic protocol composed of measurement of Na+ and K+ in serum and 24-h urine, sitting plasma renin activity, and aldosterone at baseline and after 50 mg captopril. The patients with an aldosterone/renin ratio >40 at baseline, and/or >30 after captopril, and/or a probability of PA (by a logistic discriminant function) > or =50% underwent imaging tests and adrenal vein sampling (AVS) or adrenocortical scintigraphy to identify the underlying adrenal pathology. An aldosterone-producing adenoma (APA) was diagnosed in patients who in addition to excess autonomous aldosterone secretion showed: 1) lateralized aldosterone secretion at AVS or adrenocortical scintigraphy, 2) adenoma at surgery and pathology, and 3) a blood pressure decrease after adrenalectomy. Evidence of excess autonomous aldosterone secretion without such criteria led to a diagnosis of idiopathic hyperaldosteronism (IHA). RESULTS: A total of 1,180 patients (age 46 +/- 12 years) were enrolled; a conclusive diagnosis was attained in 1,125 (95.3%). Of these, 54 (4.8%) had an APA and 72 (6.4%) had an IHA. There were more APA (62.5%) and fewer IHA cases (37.5%) at centers where AVS was available (p = 0.002); the opposite occurred where AVS was unavailable. CONCLUSIONS: In newly diagnosed hypertensive patients referred to hypertension centers, the prevalence of APA is high (4.8%). The availability of AVS is essential for an accurate identification of the adrenocortical pathologies underlying PA.     

The utility of three different methods for measuring urinary 18-hydroxycortisol in the differential diagnosis of suspected primary hyperaldosteronism

OBJECTIVE: Urine 18-hydroxycortisol (18-OHF) measurements are claimed to discriminate between primary hyperaldosteronism due to Conn's syndrome/adrenal adenoma or idiopathic bilateral adrenal hyperplasia (BAH), and also to identify cases of glucocorticoid-suppressible hyperaldosteronism (GSH). We have evaluated three urine 18-OHF methods using a panel of urine samples from patients with hypertension. DESIGN: Clinical methods comparative study. METHODS: Urine samples from patients with primary hyperaldosteronism due to either adenoma (n = 6), BAH (n = 6), GSH (n = 9), or essential hypertension (n = 38) were analysed without knowledge of the diagnosis using three different methods in different laboratories. These included 'in-house' radioimmunoassay (RIA), 'in-house' time-resolved fluorometric assay (DELFIA), and gas chromatography mass spectrometry (GC-MS). RESULTS: The three assays showed good correlation, but there were large bias differences: RIA bias was greater than DELFIA which was greater than GC-MS. Discrimination between adenoma and BAH patients was best for the DELFIA method, with no overlap between results for these two groups. All three methods gave significantly elevated results for the GSH group compared with the BAH and essential hypertension groups. No assay distinguished BAH from essential hypertension. CONCLUSION: Measurement of urine 18-OHF may be a useful additional test in the differential diagnosis of primary hyperaldosteronism. The clinical diagnostic value of urinary 18-OHF measurements is method-dependent with the DELFIA assay having the best discriminatory value.     

Measurement of 18-hydroxycorticosterone during adrenal vein sampling for primary aldosteronism

CONTEXT: In primary aldosteronism, elevated serum 18-hydroxycorticosterone (18OHB) suggests aldosterone-producing adenoma (APA) rather than bilateral, idiopathic hyperaldosteronism (IHA), but little is known about the relative production of 18OHB and aldosterone (A) in APAs compared with IHA. OBJECTIVES: We measured 18OHB, A, and cortisol (F) in blood from adrenal vein sampling (AVS) studies. We compared the discriminatory power of gradients in 18OHB/A and 18OHB/F ratios with A/F ratio gradients for distinguishing APA from IHA. DESIGN, SETTING, AND SUBJECTS: We measured 18OHB and A in excess serum from 23 AVS studies performed at our university hospitals. MAIN OUTCOME MEASURES: We calculated the ratios 18OHB/A, 18OHB/F, and A/F for all specimens, and determined the adrenal vein gradients for these ratios. RESULTS: The 18OHB/A ratios were much lower in blood draining APAs (2.17 +/- 0.62) than in blood draining the contralateral adrenals (12.96 +/- 12.76; P < 0.001) but similar to blood draining IHA adrenals (4.69 +/- 4.32; P = 0.02). In contrast, the 18OHB/F ratios were elevated in specimens from APAs (26.03 +/- 11.51) compared with IHA adrenals (9.22 +/- 5.18; P < 0.001) or the contralateral adrenals (6.23 +/- 2.97; P < 0.001). Using 18OHB/F gradient greater than two or 18OHB/A gradient less than 0.5 as criteria for lateralization, interpretations agreed with lateralizations based on A/F gradients in 21 of 23 cases. CONCLUSIONS: High serum 18OHB in APA reflects augmented production of both 18OHB and A, not disproportionate 18OHB secretion relative to A. The 18OHB/A and 18OHB/F gradients are useful adjuncts but not as reliable as A/F gradients for A lateralization during AVS.     

肾上腺肿瘤45例临床分析

目的　探讨肾上腺肿瘤的临床特点和检查方法 ,提高术前诊断水平。方法　对 4 5例肾上腺肿瘤及增生的临床表现、激素水平、CT定位诊断及术后病理进行回顾性分析。结果　 4 5例中醛固酮瘤 15例 ,误诊的双侧肾上腺增生 3例 ,嗜铬细胞瘤 8例 ,腺瘤、腺癌型皮质醇增多症 4例和意外瘤 15例。结论　术前肿瘤性质及内分泌功能检查有利于术前准备、术中处理及术后并发症预防     

Comparison of active renin concentration and plasma renin activity for the diagnosis of primary hyperaldosteronism in patients with an adrenal mass

OBJECTIVE: Plasma aldosterone concentration (PAC) to plasma renin activity (PRA) ratio is an established screening test for primary hyperaldosteronism. Due to the increased recognition of adrenal incidentalomas, reliable parameters are required. Determination of active renin concentration (ARC) in contrast to PRA offers advantages with regard to processing and standardization. The present study compared PRA and ARC under random conditions to establish thresholds for the diagnosis of primary hyperaldosteronism. DESIGN AND METHODS: Fifty patients with various adrenal tumors, including ten patients with aldosterone-secreting adrenal adenomas, as well as ten hypertensive patients and 23 normotensive volunteers were studied. PAC and PRA were measured by radioimmunoassay. ARC was determined by an immunoluminometric assay. RESULTS: Receiver operating curve (ROC) analysis suggested a PAC to ARC ratio threshold of 90 ((ng/l)/(ng/l)) (sensitivity 100%, specificity 98.6%) and a ratio threshold of 62 by additional consideration of PAC > or =200 ng/l (sensitivity 100%, specificity 100%) for the diagnosis of aldosterone-secreting adrenal adenomas. CONCLUSIONS: A PAC to ARC ratio of > or =62 in patients with PAC levels > or =200 ng/l is a reliable screening method for primary hyperaldosteronism in patients with an aldosterone-producing adenoma under random conditions. Because of its advantages with regard to probe processing and its independence from endogenous angiotensinogen levels, ARC may be preferred to PRA.     

A prospective evaluation of postural stimulation testing, computed tomography and adrenal vein sampling in the differential diagnosis of primary aldosteronism

Context In primary aldosteronism (PA), discriminating unilateral from bilateral disease is crucial because adrenalectomy is frequently curative in the former case but rarely helps in the latter. Various series have reported the utility of postural stimulation testing (PST), cross‐sectional imaging and adrenal vein sampling (AVS) in the assessment of PA, but most of these studies were retrospective. Objective To prospectively determine the diagnostic utility of PST, AVS and computed tomography (CT) using a radiological scoring system in the assessment of PA in a tertiary centre, as well as to document the incidence of autonomous cortisol cosecretion. Design and Setting Fifty consecutive patients with PA underwent PST, CT, AVS and a low‐dose dexamethasone suppression test with measurement of serum cortisol at 48 h. For patients who underwent surgery, histological confirmation, and a normal postoperative serum aldosterone concentration and plasma renin activity were taken as evidence for unilateral disease. For other patients, results from successful adrenal vein sampling were the diagnostic evidence against which CT and PST were assessed. Results Postural stimulation testing had a sensitivity and specificity of 44–56% and 71–75%, respectively. CT had an overall sensitivity and specificity of 77% and 80%, respectively, rising to 100% sensitivity and specificity if there was a single, discrete macronodule with an unequivocally normal contralateral gland. Evidence of cosecretion of cortisol occurred in 14% of patients. Conclusions Preliminary experience is presented of an objective radiological scoring system for selecting patients with PA for AVS. PST provides little, if any, useful additional information. A significant minority of patients with PA exhibit evidence of cortisol cosecretion, which may have implications for perioperative management.