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Wiebke Arlt

Androgens in women either derive from direct ovarian production or from peripheral conversion of the adrenal sex steroid precursor, dehydroepiandrosterone, towards active androgens. Therefore, loss of adrenal or ovarian function, caused by Addison’s disease or consequent to bilateral oophorectomy, results in severe androgen deficiency, clinically often associated with a loss of libido and energy. Importantly, physiological menopause does not necessarily lead to androgen deficiency, as androgen synthesis in the ovaries may persist despite the decline in estrogen production. However, the definition of female androgen deficiency, as recently provided by the Princeton consensus statement, is not precise enough and may lead to over-diagnosis due to the high prevalence of its diagnostic criteria: androgen levels below or within the lower quartile of the normal range and concurrent sexual dysfunction. Importantly, physiological menopause is not necessarily associated with androgen deficiency and therefore does not routinely require androgen therapy. Current replacement options include transdermal testosterone administration or dehydroepiandrosterone treatment, both of which have been shown to result in significant improvements, in particular in libido and mood, while effects on body composition and muscular function are not well documented. It is important to keep in mind that the number of randomized controlled trials is still limited and that currently none of the available preparations is officially approved for use in women. Currently, androgen replacement should be reserved for women with severe androgen deficiency due to an established cause and matching clinical signs and symptoms.

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Katherine White and Wiebke Arlt

Context

Adrenal crisis is a life-threatening event that occurs regularly in Addison's patients receiving standard replacement therapy. Patient reports suggest that it is an underestimated and under-managed event.

Objective

To assess the frequency of adrenal crisis in diagnosed patients and to understand the factors contributing to the risks of adrenal crisis.

Design

We conducted a postal survey of Addison's patients in four countries, UK (n=485), Canada (n=148), Australia (n=123) and New Zealand (n=85) in 2003, asking about patients' experiences of adrenal crisis and their demographic characteristics. In 2006, a shorter follow-up survey was conducted in the UK (n=261).

Method

The frequency and causes of adrenal crisis were compared across both surveys. Demographic data from the 2003 survey were analysed to establish the main variables associated with an elevated risk of crisis.

Results

Around 8% of diagnosed cases can be expected to need hospital treatment for adrenal crisis annually. Exposure to gastric infection is the single most important factor predicting the likelihood of adrenal crisis. Concomitant diabetes and/or asthma increase the frequency of adrenal crises reported by patients.

Conclusion

The endocrinologist has a responsibility to ensure that Addison's patients have adequate access to life-saving emergency injection materials and repeated, practical training sessions in how to use them, while the general practitioner plays a vital role as in arranging prompt emergency admissions.

Open access

Lina Schiffer, Punith Kempegowda, Wiebke Arlt and Michael W O’Reilly

Female androgen excess and male androgen deficiency manifest with an overlapping adverse metabolic phenotype, including abdominal obesity, insulin resistance, type 2 diabetes mellitus, non-alcoholic fatty liver disease and an increased risk of cardiovascular disease. Here, we review the impact of androgens on metabolic target tissues in an attempt to unravel the complex mechanistic links with metabolic dysfunction; we also evaluate clinical studies examining the associations between metabolic disease and disorders of androgen metabolism in men and women. We conceptualise that an equilibrium between androgen effects on adipose tissue and skeletal muscle underpins the metabolic phenotype observed in female androgen excess and male androgen deficiency. Androgens induce adipose tissue dysfunction, with effects on lipid metabolism, insulin resistance and fat mass expansion, while anabolic effects on skeletal muscle may confer metabolic benefits. We hypothesise that serum androgen concentrations observed in female androgen excess and male hypogonadism are metabolically disadvantageous, promoting adipose and liver lipid accumulation, central fat mass expansion and insulin resistance.

Open access

Irina Bancos, Jon Hazeldine, Vasileios Chortis, Peter Hampson, Angela E Taylor, Janet M Lord and Wiebke Arlt

Objective

Mortality in patients with primary adrenal insufficiency (PAI) is significantly increased, with respiratory infections as a major cause of death. Moreover, patients with PAI report an increased rate of non-fatal infections. Neutrophils and natural killer (NK) cells are innate immune cells that provide frontline protection against invading pathogens. Thus, we compared the function and phenotype of NK cells and neutrophils isolated from PAI patients and healthy controls to ascertain whether altered innate immune responses could be a contributory factor for the increased susceptibility of PAI patients to infection.

Design and methods

We undertook a cross-sectional study of 42 patients with PAI due to autoimmune adrenalitis (n = 37) or bilateral adrenalectomy (n = 5) and 58 sex- and age-matched controls. A comprehensive screen of innate immune function, consisting of measurements of neutrophil phagocytosis, reactive oxygen species production, NK cell cytotoxicity (NKCC) and NK cell surface receptor expression, was performed on all subjects.

Results

Neutrophil function did not differ between PAI and controls. However, NKCC was significantly reduced in PAI (12.0 ± 1.5% vs 21.1 ± 2.6%, P < 0.0001). Phenotypically, the percentage of NK cells expressing the activating receptors NKG2D and NKp46 was significantly lower in PAI, as was the surface density of NKG2D (all P < 0.0001). Intracellular granzyme B expression was significantly increased in NK cells from PAI patients (P < 0.01).

Conclusions

Adrenal insufficiency is associated with significantly decreased NKCC, thereby potentially compromising early recognition and elimination of virally infected cells. This potential impairment in anti-viral immune defense may contribute to the increased rate of respiratory infections and ultimately mortality in PAI.

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Anna C Phillips, Douglas Carroll, Catharine R Gale, Janet M Lord, Wiebke Arlt and G David Batty

Objectives

The aim of the present analyses was to examine the association between cortisol, DHEA sulphate (DHEAS) and the cortisol:DHEAS ratio and mortality.

Design

This was a prospective cohort analysis.

Methods

Participants were 4255 Vietnam-era US army veterans. From military service files, telephone interviews and a medical examination, occupational, socio-demographic and health data were collected. Contemporary morning fasted cortisol and DHEAS concentrations were determined. Mortality was tracked over the subsequent 15 years. The outcomes were all-cause, cardiovascular disease, cancer, other medical mortality and external causes of death. Cox proportional hazard models were tested, initially with adjustment for age, and then with adjustment for a range of candidate confounders.

Results

In general, cortisol concentrations did not show an association with all-cause or cause-specific mortality. However, in age-adjusted and fully adjusted analyses, DHEAS was negatively related to all-cause, all cancers and other medical mortality; high DHEAS concentrations were protective. The cortisol:DHEAS ratio was also associated with these outcomes in both age-adjusted and fully adjusted models; the higher the ratio, the greater the risk of death.

Conclusions

DHEAS was negatively associated, and the ratio of cortisol to DHEAS was positively associated with all-cause, cancer and other medical cause mortality. Further experimental study is needed to elucidate the mechanisms involved in these relationships.

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Anna C Phillips, Douglas Carroll, Catharine R Gale, Janet M Lord, Wiebke Arlt and G David Batty

Objectives

The aim of these analyses was to examine the association of cortisol, DHEAS and the cortisol:DHEAS ratio with the metabolic syndrome (MetS) and its components.

Design

The analyses were cross-sectional.

Methods

Participants were 4255 Vietnam era US army veterans. From military service files, telephone interviews and a medical examination, occupational, socio-demographic and health data were collected. MetS was ascertained from data on body mass index; fasting blood glucose or a diagnosis of diabetes; blood pressure or a diagnosis of hypertension; high-density lipoprotein cholesterol; and triglyceride levels. Contemporary morning fasted cortisol and DHEAS concentrations were determined. The outcomes were MetS and its components. Analysis was by logistic regression, first adjusting for age and then additionally for an array of candidate confounders.

Results

Cortisol, although not in the fully adjusted analysis, and DHEAS were both related to MetS. Whereas high cortisol concentrations were associated with an increased risk of MetS, high DHEAS concentrations appeared protective. By far, the strongest associations with MetS were observed for the cortisol:DHEAS ratio; the higher the ratio, the greater the risk of having MetS. The ratio was also significantly related to four of the five MetS components.

Conclusions

The cortisol:DHEAS ratio is positively associated with MetS. Prospective analyses are needed to help untangle direction of causality, but this study suggests that the cortisol:DHEAS ratio is worthy of further study in this and other health contexts.

Open access

Dorota Tomalik-Scharte, Dominique Maiter, Julia Kirchheiner, Hannah E Ivison, Uwe Fuhr and Wiebke Arlt

Objective

Patients with congenital adrenal hyperplasia due to P450 oxidoreductase (POR) deficiency (ORD) present with disordered sex development and glucocorticoid deficiency. This is due to disruption of electron transfer from mutant POR to microsomal cytochrome P450 (CYP) enzymes that play a key role in glucocorticoid and sex steroid synthesis. POR also transfers electrons to all major drug-metabolizing CYP enzymes, including CYP3A4 that inactivates glucocorticoid and oestrogens. However, whether ORD results in impairment of in vivo drug metabolism has never been studied.

Design

We studied an adult patient with ORD due to homozygous POR A287P, the most frequent POR mutation in Caucasians, and her clinically unaffected, heterozygous mother. The patient had received standard dose oestrogen replacement from 17 until 37 years of age when it was stopped after she developed breast cancer.

Methods

Both subjects underwent in vivo cocktail phenotyping comprising the oral administration of caffeine, tolbutamide, omeprazole, dextromethorphan hydrobromide and midazolam to assess the five major drug-metabolizing CYP enzymes. We also performed genotyping for variant CYP alleles known to affect drug metabolism.

Results

Though CYP enzyme genotyping predicted normal or high enzymatic activities in both subjects, in vivo assessment showed subnormal activities of CYP1A2, CYP2C9, CYP2D6 and CYP3A4 in the patient and of CYP1A2 and CYP2C9 in her mother.

Conclusions

Our results provide in vivo evidence for an important role of POR in regulating drug metabolism and detoxification. In patients with ORD, in vivo assessment of drug-metabolizing activities with subsequent tailoring of drug therapy and steroid replacement should be considered.

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Irina Bancos, Shrikant Tamhane, Muhammad Shah, Danae A Delivanis, Fares Alahdab, Wiebke Arlt, Martin Fassnacht and M Hassan Murad

Objective

To perform a systematic review of published literature on adrenal biopsy and to assess its performance in diagnosing adrenal malignancy.

Methods

Medline In-Process and Other Non-Indexed Citations, MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trial were searched from inception to February 2016. Reviewers extracted data and assessed methodological quality in duplicate.

Results

We included 32 observational studies reporting on 2174 patients (39.4% women, mean age 59.8 years) undergoing 2190 adrenal mass biopsy procedures. Pathology was described in 1621/2190 adrenal lesions (689 metastases, 68 adrenocortical carcinomas, 64 other malignancies, 464 adenomas, 226 other benign, 36 pheochromocytomas, and 74 others). The pooled non-diagnostic rate (30 studies, 2013 adrenal biopsies) was 8.7% (95%CI: 6–11%). The pooled complication rate (25 studies, 1339 biopsies) was 2.5% (95%CI: 1.5–3.4%). Studies were at a moderate risk for bias. Most limitations related to patient selection, assessment of outcome, and adequacy of follow-up. Only eight studies (240 patients) could be included in the diagnostic performance analysis with a sensitivity and specificity of 87 and 100% for malignancy, 70 and 98% for adrenocortical carcinoma, and 87 and 96% for metastasis respectively.

Conclusions

Evidence based on small sample size and moderate risk of bias suggests that adrenal biopsy appears to be most useful in the diagnosis of adrenal metastasis in patients with a history of extra-adrenal malignancy. Adrenal biopsy should only be performed if the expected findings are likely to alter the management of the individual patient and after biochemical exclusion of catecholamine-producing tumors to help prevent potentially life-threatening complications.

Open access

Silvia Parajes, Angel OK Chan, W M But, Ian T Rose, Angela E Taylor, Vivek Dhir, Wiebke Arlt and Nils Krone

Context

Cytochrome P450 side-chain cleavage enzyme (CYP11A1) catalyses the first and rate-limiting step of steroidogenesis, the conversion of cholesterol to pregnenolone. CYP11A1 deficiency is commonly associated with adrenal insufficiency, and in 46,XY individuals, with variable degrees of disorder of sex development (DSD).

Patient and methods

The patient was born with hyperpigmentation, micropenis, penoscrotal hypospadias, and mild cryptorchidism. Biochemical and hormonal findings were normal except for low testosterone and low-borderline cortisol. However, no short synacthen test was undertaken. Development was unremarkable apart from an episode labeled as sepsis with documented hyperkalemia and elevated C-reactive protein at age 15 days. Diagnosis of 46,XY DSD was made at age 2.5 months. Progression of hyperpigmentation prompted further investigations and the diagnosis of adrenal insufficiency was established at 2 years with raised ACTH, normal renin activity, and failure of cortisol to respond to short synacthen test. Genetic analyses were performed. The novel CYP11A1 mutations were characterized in vitro and in silico.

Results

The patient was compound heterozygous for two novel CYP11A1 mutations, p.R360W and p.R405X. p.R360W retained 30–40% of wild-type activity. In silico analyses confirmed these findings and indicated that p.R405X is severe.

Conclusions

This study demonstrates the pathogenicity of two novel CYP11A1 mutations found in a patient with delayed diagnosis of CYP11A1 deficiency. Patients with partial deficiencies of steroidogenic enzymes are at risk to be misdiagnosed if adrenal function is not assessed. The adrenocortical function should be routinely assessed in all patients with DSD including severe hypospadias of unknown origin to prevent life-threatening adrenal crises.