Background: Adrenal adenomas showing autonomous cortisol secretion without specific endocrine symptoms are sometimes discovered in patients with adrenal incidentalomas. This entity has been described as subclinical or preclinical Cushing's syndrome (PCS), but the endocrine data of reported cases have varied and the diagnostic criteria of PCS have been uncertain. Methods:We report seven Japanese cases of PCS due to a unilateral, solitary adrenal adenoma with examination of the endocrine data of these patients. The diagnostic parameters of subtle hypercortisolism and the risk of postoperative adrenal insufficiency and surgical indications are discussed and reviewed. Results: In the present cases, the most frequently found biochemical parameters of autonomous cortisol secretion were a low adrenocorticotropic hormone (ACTH) level (100%) and insufficient suppression of cortisol by low-dose dexamethasone (85.7%). Unilateral accumulation of radiopharmaceuticals in tumors was also frequently observed (100%). A postoperative hydrocortisone supplement was given to six of the seven patients for 5-122 days. It was not given to case 4, because a moderate response of 11-deoxycortisol to metyrapone was identified. Plasma ACTH levels and the diurnal rhythm of plasma cortisol rapidly recovered within 3 weeks postoperatively in six of the seven cases. Conclusion:This entity is heterogeneous and various degrees of cortisol excess have been observed. It should be diagnosed in the wide spectrum and the risk of adrenal insufficiency after surgery should be evaluated by dynamic tests such as the corticotropin-releasing hormone (CRH) test. Based on the results of the present study and a review of the literature, PCS patients may not require hydrocortisone supplement therapy for a long period.

This paper reports a case of an idiopathic renal arteriovenous fistula demonstrating a huge guitar-shaped aneurysm, which required a total nephrectomy. Although the patient insisted on having been asymptomatic, echocardiography and cardiac catheterization clearly revealed that the influence on hemodynamics was unexpectedly significant. Interestingly, the aneurysm was also considered to have a high risk of rupture, which was preoperatively suggested by an aneurysm wall projection discernible on both computerized tomograms and angiograms, and this suspicion was also convincingly supported by the perioperative and histopathological findings.

3-Hydroxy-3-methylglutaryl coenzyme A reductase (NADPH) was solubilized by trypsin digestion from sliced potato tuber microsomes, and purified to apparent homogeneity in the absence of detergent with a recovery of 1.8%. The enzyme had a specific activity of 7,910 nmol of mevalonate formed per min per mg of protein. On molecular-sieving high-performance liquid chromatography, the activity was coincident with the single protein peak corresponding to a molecular weight of approximately 110 kDa. On SDS-polyacrylamide gel electrophoresis, the purified enzyme showed only one protein staining band corresponding to a molecular weight of approximately 55 kDa. The apparent Km value for S-HMG-CoA was 6.4 microM and that for NADPH was 25 microM.

This paper reports a case of an idiopathic renal arteriovenous fistula demonstrating a huge guitar-shaped aneurysm, which required a total nephrectomy. Although the patient insisted on having been asymptomatic, echocardiography and cardiac catheterization clearly revealed that the influence on hemodynamics was unexpectedly significant. Interestingly, the aneurysm was also considered to have a high risk of rupture, which was preoperatively suggested by an aneurysm wall projection discernible on both computerized tomograms and angiograms, and this suspicion was also convincingly supported by the perioperative and histopathological findings.

No abstract