Hyperaldosteronism: How to Discriminate Among Different Disease Forms?

Characteristics of preoperative steroid profiles and glucose metabolism in patients with primary aldosteronism developing adrenal insufficiency after adrenalectomy

Treatment of choice in patients with unilateral aldosterone producing adenoma (APA) is adrenalectomy. Following surgery, most patients retain normal adrenal function, while some develop adrenal insufficiency (AI). To facilitate early detection and treatment of AI, we aimed to identify variables measured pre-operatively that are associated with post-operative AI. Variables obtained from 66 patients before and after surgery included anthropometrical data, clinical chemistry, endocrine work-up. LC–MS/MS steroid hormone profiles from tests before surgery (ACTH-stimulation, saline infusion, dexamethasone suppression) were obtained. Based on 78 variables, machine-learning methods were used in model fitting for classification and regression to predict ACTH-stimulated cortisol after surgery. Among the 78 variables, insulin concentration during pre-operative oral glucose tolerance test (OGTT) correlated positively, and dexamethasone suppressed glucocorticoids correlated negatively with ACTH-stimulated cortisol after surgery. Inclusion of LC–MS/MS measurements allowed construction of better models associated with the occurrence of AI in the training data, but did not allow reliable prediction in cross-validation. Our results suggest that glucocorticoid co-secretion (low insulin during pre-operative OGTT and insufficient suppression of glucocorticoids following dexamethasone) are correlated with the development of post-operative AI. Addition of steroid profiles improved the accuracy of prediction, but cross validation revealed lack of reliability in the prediction of AI.

Familial hyperaldosteronism type III a novel case and review of literature

Less than 15% of hypertension cases in children are secondary to a primary hyperaldosteronism. This is idiopathic in 60% of the cases, secondary to a unilateral adenoma in 30% and 10% remaining by primary adrenal hyperplasia, familial hyperaldosteronism, ectopic aldosterone production or adrenocortical carcinoma.To date, four types of familial hyperaldosteronism (FH I to FH IV) have been reported. FH III is caused by germline mutations in KCNJ5, encoding the potassium channel Kir3.4. The mutations cause the channel to lose its selectivity for potassium, allowing large quantities of sodium to enter the cell. As a consequence, the membrane depolarizes, voltage-gated calcium channels open, calcium enters the cell, initiating the cascade that leads to aldosterone synthesis. Somatic mutations in KCNJ5 has also been described in aldosterone-producing adenomas. The most frequent presentation of FH III is with severe hyperaldosteronism symptoms and resistance to pharmacological therapy which leads to bilateral adrenalectomy. We will review current literature and describe a child with FH III due to a novel de novo deletion in KCNJ5 with wild phenotype as a sign of clinical variability of this disease.

Endocrine Tumors Causing Arterial Hypertension: Pathophysiological Mechanisms and Clinical Implications

Some tumors are a relatively rare and amendable cause of hypertension, often associated with a higher cardiovascular morbidity and mortality, as compared with that of both general population and patients with essential hypertension. This worse prognosis is not entirely related to blood pressure increase, because the release of substances from the tumor can directly influence blood pressure behavior. Diagnostic approach is challenging and needs a deep knowledge of the different neuro-hormonal and genetic mechanisms determining blood pressure increase. Surgical tumor removal can, but not always, cause blood pressure normalization, depending on how early was tumor detection, since a long-standing history of hypertension is often associated with a much weaker effect on blood pressure. Moreover, target organ damage can be affected by the substances themselves released by the tumors as well as by tumor removal. In this review we consider the phenotype and genetic features of patients with tumor-induced hypertension and focus on their diagnostic work-up.