[The Diagnostic Value of Captopril Challenge Test for Primary Aldosteronism].

OBJECTIVE: To investigate the diagnostic value of different captopril challenge test (CCT) diagnostic criteria for diagnosing primary aldosteronism (PA). METHODS: We collected the clinical data of 184 patients with hypertension retrospectively in West China Hospital of Sichuan University. Receiver operating characteristic (ROC) curves were used to analyze the post-CCT efficacy of aldosterone renin activity ratio (ARR), plasma aldosterone concentration (PAC), plasma renin activity (PRA) and PAC suppression rate for PA diagnosis. RESULTS: This study included 125 cases of primary aldehyde (PA group) and 59 cases of essential hypertension (EH group), and there were 38 normal renin primary hypertension (NREH group) and 21 low renin primary hypertension (LREH group) in EH group. The post-CCT PAC suppression rate (median (P 25, P 75)) of EH and PA group were 0.190 (0.083, 0.351) and 0.125 (0.024, 0.237), respectively. Compared with the NREH group, the basic and post-CCT PRA of LREH group were lower ( P<0.001), and there were no significant differences compared with the PA group ( P>0.05). We found significant overlap of post-CCT PRA and ARR between PA group and LREH group, while the overlap of post-CCT PAC between the two groups was small. In differential diagnosis of PA and EH, the areas under ROC curve of the post-CCT ARR, PAC, PRA and PAC suppression rate were 0.860 (95% confidence interval ( CI): 0.800-0.907), 0.881 (95% CI: 0.825-0.924), 0.771 (95% CI: 0.703-0.831) and 0.632 (95% CI: 0.558-0.701), respectively. There was no significant difference between the first two indexes ( Z=0.443, P=0.658), and both of them were higher than the latter two ( P<0.05). The optimal post-CCT cut-off values for ARR and PAC in differential diagnosis of PA and EH were 19.24 ng·dL -1 with a sensitivity of 78.4% and a specificity of 88.1%, and 32.47 (ng·dL -1)/(ng·mL -1·h -1) with a sensitivity of 84.17% and a specificity of 72.41%. CONCLUSION: Both ARR and PAC have higher diagnostic value than the post-CCT PAC suppression rate, post-CCT PAC is especially suitable as a confirmatory testing criterion of PA.

[The Value of Postural Stimulation Test Combined with Adrenal CT in the Diagnosis of Aldosterone-producing Adenoma].

OBJECTIVE: Adrenal vein sampling (AVS) and pathological report were selected as gold standard to assess the value of adrenal CT scan combined with postural stimulation test in diagnosing aldosterone-producing adenoma. METHODS: The clinical data of primary aldosteronism (PA) patients including aldosterone-producing adenoma (APA) and idiopathic hyperaldosteronism (IHA) were retrospectively collected in the West China Hospital of Sichuan University. The sensitivity and specificity of adrenal CT scan combined with postural stimulation test in diagnosing APA were studied. RESULTS: A total of 83 APA patients and 42 IHA patients were enrolled in this study. ROC curve was plotted with increase percentage of serum aldosterone in upright position compared with recumbent position. The optimal cutoff point for APA diagnosis by postural stimulation test was 11%, and the percentage less than 11% was taken as a positive result. The patients were diagnosed by postural stimulation test, with 60 cases positive and 23 cases negative in APA patients and 12 cases positive and 30 cases negative in IHA patients. When AVS and pathological report were selected as the gold standard, the sensitivity and specificity of postural stimulation test in diagnosing APA were 72.3% and 71.4% respectively. Among the 83 APA patients, 65 patients with unilateral nodules and 18 patients with bilateral nodules were diagnosed by CT scan. The coincidence rate in APA diagnosis between CT scan and AVS or pathological report was 78.3% (65/83). Among the 60 patients with positive result in postural stimulation test, who were diagnosed bilateral nodules by CT scan, 51 patients were diagnosed as APA by AVS or pathological report (51/60). CONCLUSION: Adrenal CT combined with postural test can increase the diagnostic accuracy of APA patients.