Endocrine Abstracts

A key component of androgen synthesis is the availability of the pro-hormone DHEA, which is either converted to active androgens or inactivated to its sulfate ester DHEAS by DHEA sulfotransferase (SULT2A1). The latter reaction requires provision of the universal sulfate donor 3′-phosphoadenosine-5′-phosphosulfate, PAPS. In humans, PAPS is generated by the PAPS synthase isoforms PAPSS1 and PAPSS2. Recently, inactivating PAPSS2 mutations have been identified i...

Background: Adrenal insufficiency is a well-recognised feature of congenital adrenal hyperplasia (CAH).CAH is commonly treated with oral steroid replacement, taken 2–3 times a day, at doses that aim to reproduce normal diurnal variation. Though acceptable for most patients, this does not control others, resulting in high levels of 17-hydroxyprogesterone-acetate (17OHP), ACTH, and the need for increased doses of steroid replacement, with associated c...

Congenital adrenal hyperplasia due to steroid 21-hydroxylase deficiency (21OHD) is the commonest inborn error in steroid biosynthesis. It is caused by mutations in the 21-hydroxylase gene (CYP21A2). A good genotype–phenotype correlation exists allowing for prediction of the expressed adrenal phenotype. We performed functional and structural analysis of six novel CYP21A2 variants (p.Trp22Cys; p.Asp184Asn; p.Leu198Phe; p.Val305Gly; p.His310Asn; p.Thr443Asn), i...

Objective: Isolated ACTH-deficiency (IAD) is considered a rare autoimmune endocrinopathy most frequently associated with autoimmune thyroid diseases (ATD). We have previously diagnosed IAD in four patients with primary hypothyroidism and negative TPO antibodies. The aim of this study was to determine the prevalence of undiagnosed IAD in patients with ATD.Methods: We studied 45 patients with ATD on stable L-thyroxine replacement (dose range...

The role of endogenous glucocorticoid (GC) production and metabolism in the pathogenesis of obesity, insulin resistance and type 2 diabetes remains unclear. Patients with Cushing’s syndrome develop central obesity, insulin resistance and in some cases type 2 diabetes (T2DM), yet circulating cortisol levels are not elevated in simple obesity. Alterations in GC metabolism, including 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) that generates active cortisol ...

Cranial radiotherapy is widely used in combination with chemotherapy to treat patients with primary brain tumours. Increased survival has lead to the recognition of long term sequelae, including endocrine dysfunction due to radiation-induced hypothalamic–pituitary damage. Here we assessed health-related quality of life and endocrine function in 31 adult long term survivors (median age 45, range 29–65 years; 21M, 10F) of primary brain tumours outside the hypothalamic&...

The diagnosis of Cushing’s syndrome (CS) remains a major clinical challenge especially in a proportion of patients that have discordant results in the available tests. Although the measurement of 24-h urine free cortisol (UFC) is a useful test for the diagnosis of CS, 10–15% of patients have at least one measurement within the normal range and multiple measurements may be required in order to raise its sensitivity. In this study we sought to evaluate the value of the...

Stress results in activation of the hypothalamic–pituitary–adrenal axis with increased circulating cortisol. It has been argued that a syndrome of ‘relative adrenal insufficiency’ is common in critically ill patients. Patients who fail to increase their cortisol by >250 nmol/30 min following the administration of 250 μg ACTH in the short synacthen test (SST) have been reported to have a higher mortality (JAMA 2000, 283 1038–1045)...

Congenital adrenal hyperplasia (CAH) caused by mutations in the electron donor enzyme P450 oxidoreductase (POR) is unique amongst all CAH variants in that it can be associated with ambiguous genitalia (disordered sex differentiation, DSD) both in 46,XX and 46,XY individuals. POR has a pivotal role in facilitating electron transfer from NADPH to microsomal P450 enzymes, including CYP17, which catalyses a key step in human androgen synthesis, the conversion of 17-hydroxypregneno...

Androgen excess is a key feature of polycystic ovarian syndrome (PCOS). Pre-receptor regulation contributes to this with increased activation of testosterone (T) to 5α-dihydrotesterone (DHT) by 5α-reductase type 1 (SRD5A1), as we have shown previously in PCOS (Lancet 1990,335:431; JCE&M 2003,88:2760). Peripheral blood mononuclear cells (PBMCs) are easily accessible and a useful model for studying pre-receptor regulation in the immune compartment. We have previous...