Primary aldosteronism (PA) is the most common form of secondary hypertension, and is characterized by high plasma aldosterone concentration (PAC) and low plasma renin activity (PRA), refractory hypertension, and occasional hypokalemia. Reliable parameters are required to identify aldosterone-producing adenoma (APA) in patients with PA, because APA is treatable with surgical resection if localization of aldosterone hypersecretion can be determined by adrenal venous sampling (AVS). The purpose of this study is to summarize the results of AVS in our institute and to evaluate the diagnostic accuracy of various parameters with adrenocorticotropic hormone (ACTH) stimulation test in identifying probable APA among patients with PA. Eighty-one patients with PA were admitted to Shinshu University Hospital from April 2009 to March 2013, and 59 patients who underwent AVS were included in the study. PAC and aldosterone to potassium ratio (APR) in ACTH stimulation tests were examined in 28 patients. Receiver operating characteristic (ROC) curve analysis was used to evaluate diagnostic accuracy. The response of PAC to ACTH in the probable APA group was stronger than that in the others. In ROC curve analysis, the area under the curve (AUC) of APR (PAC_30min/potassium) for diagnosis of probable APA was 0.9840 with an optimal cutoff value＞102.6 corresponding to sensitivity and specificity of 94.1% and 90.9% for diagnosis of APA, respectively. This study indicated that APR after the ACTH stimulation test may be a useful and accurate parameter in cases of PA. In cases with APR≥100 after ACTH stimulation, AVS is strongly recommended for localization of aldosterone hypersecretion.

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Objective : Endothelial PER-ARNT-SIM (PAS) domain protein 1 (EPAS1, also known as HIF2α) and egl nine homolog 1 (EFLN1), also known as prolyl hydroxylase domain protein 2 (PHD2), have key functions in the upstream of the hypoxia-inducible factor (HIF) pathway. In order to dissect the genetic biology of susceptibility to high-altitude pulmonary edema (HAPE) from the viewpoint of the HIF pathway, we identified the allelic discriminations of three significant tag single-nucleotide polymorphisms (SNPs) in EPAS1 and three tag SNPs in EGLN1 in HAPE-susceptible (HAPE-s) Japanese subjects.
Methods : Alleles were determined for the six SNPs (rs13419896, rs4953354, and rs4953388 in EPAS1 ; rs1435166, rs7542797, and rs2153364 in EGLN1) by the TaqMan^® SNP Genotyping Assay in a group of 59 HAPE-s subjects and a control group of 67 HAPE resistant (HAPE-r) subjects. In addition to the case-control analysis, multi-dimensional reduction (MDR) methodology was applied to a gene-gene interaction analysis to evaluate the association of HAPE-s with gene-gene interactions.
Results : The EGLN1 rs2153364 (A/G) x EPAS1 rs13419896 (G/A) interaction was significantly associated with HAPE-s in the pairwise model (P＝0.0049) based on the balanced accuracy of 63.23% in MDR. However, no significance was detected for the association with HAPE-s in the single gene model.
Conclusion : The EPAS1-EGLN1 interaction appears to be associated with HAPE-s in the Japanese population despite the individual genes not being associated with HAPE-s.

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Spontaneous isolated dissection of a visceral artery is rare. We report here two cases of isolated dissection of visceral arteries. Case 1 was a 57-year-old man and Case 2 was a man of 46, both of whom suddenly experienced severe abdominal pain without signs of peritoneal irritation. A subsequent abdominal CT scan demonstrated dissection of the superior mesenteric artery, and dissection of the celiac artery and its branches, such as splenic, hepatic, and gastroduodenal arteries, respectively. Both patients were successfully managed by conservative medical therapy with antihypertensive drugs without exacerbation. Two years have passed since onset, and there have been no findings of recurrence. There is a possibility of aneurysm formation and relapse, so it is necessary to continue close observation. It has become possible to make a definitive diagnosis of this disease at an early stage due to recent developments in diagnostic imaging. It is considered important always to keep this disease in mind as one of the differential diagnoses of sudden abdominal pain in emergency medicine.

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