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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

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.

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.

Open access

Vasileios Chortis, Nicholas J Johal, Irina Bancos, Matthew Evans, Kassiani Skordilis, Peter Guest, Michael H Cullen, Emilio Porfiri and Wiebke Arlt

Mitotane (o,p′DDD) is established in the adjuvant and advanced-stage treatment of adrenocortical carcinoma and counteracts both tumor growth and tumor-related steroid production. Both the adrenal glands and the gonads are steroidogenically active organs and share a common embryogenic origin. Here, we describe the effects of mitotane in two patients with metastatic Leydig cell tumor (LCT) of the testes and associated severe androgen excess (serum testosterone 93 and 88 nmol/L, respectively; male reference range 7–27 nmol/L). Both men suffered from severe restlessness, insomnia and irritability, which they described as intolerable and disrupting normal life activities. Urinary steroid profiling by gas chromatography–mass spectrometry (GC–MS) confirmed excess androgen production and revealed concurrent overproduction of glucocorticoids and glucocorticoid precursors, which under physiological conditions are produced only by the adrenal glands but not by the gonads. In a palliative approach, they were commenced on mitotane, which achieved swift control of the hormone excess and the debilitating clinical symptoms, restoring normal quality of life. GC–MS demonstrated normalization of steroid production and decreased 5α-reductase activity, resulting in decreased androgen activation, and imaging demonstrated disease stabilization for 4–10 months. In conclusion, mitotane can be highly effective in controlling steroid excess in metastatic LCTs, with anti-tumor activity in some cases.

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.

Open access

Jacqueline Dinnes, Irina Bancos, Lavinia Ferrante di Ruffano, Vasileios Chortis, Clare Davenport, Susan Bayliss, Anju Sahdev, Peter Guest, Martin Fassnacht, Jonathan J Deeks and Wiebke Arlt

Objective

Adrenal masses are incidentally discovered in 5% of CT scans. In 2013/2014, 81 million CT examinations were undertaken in the USA and 5 million in the UK. However, uncertainty remains around the optimal imaging approach for diagnosing malignancy. We aimed to review the evidence on the accuracy of imaging tests for differentiating malignant from benign adrenal masses.

Design

A systematic review and meta-analysis was conducted.

Methods

We searched MEDLINE, EMBASE, Cochrane CENTRAL Register of Controlled Trials, Science Citation Index, Conference Proceedings Citation Index, and ZETOC (January 1990 to August 2015). We included studies evaluating the accuracy of CT, MRI, or 18F-fluoro-deoxyglucose (FDG)-PET compared with an adequate histological or imaging-based follow-up reference standard.

Results

We identified 37 studies suitable for inclusion, after screening 5469 references and 525 full-text articles. Studies evaluated the accuracy of CT (n=16), MRI (n=15), and FDG-PET (n=9) and were generally small and at high or unclear risk of bias. Only 19 studies were eligible for meta-analysis. Limited data suggest that CT density >10HU has high sensitivity for detection of adrenal malignancy in participants with no prior indication for adrenal imaging, that is, masses with ≤10HU are unlikely to be malignant. All other estimates of test performance are based on too small numbers.

Conclusions

Despite their widespread use in routine assessment, there is insufficient evidence for the diagnostic value of individual imaging tests in distinguishing benign from malignant adrenal masses. Future research is urgently needed and should include prospective test validation studies for imaging and novel diagnostic approaches alongside detailed health economics analysis.

Open access

Kumarendran Balachandran, Dana Sumilo, Michael W O'Reilly, Konstantinos A. Toulis, Krishna Gokhale, Chandrika Wijeyaratne, Arri Coomarasamy, Wiebke Arlt, Abd Tahrani and Krishnarajah Nirantharakumar

Objective: Obesity is very common in patients with obstructive sleep apnoea (OSA) and polycystic ovary syndrome (PCOS). Longitudinal studies assessing OSA risk in PCOS and examining the role of obesity are lacking. Our objective was to assess the risk of OSA in women with vs. without PCOS and to examine the role of obesity in the observed findings.

Design: Population-based retrospective cohort study utilizing The Health Improvement Network (THIN), UK.

Methods: 76,978 women with PCOS and 143,077 age-, BMI- and location-matched women without PCOS between January 2000 and May 2017 were identified. Hazard Ratio (HR) for OSA among women with and without PCOS were calculated after controlling for confounding variables using multivariate Cox models.

Results: Median patient age was 30 (IQR: 25 – 35) years; median follow-up was 3.5 (IQR: 1.4 – 7.1) years. We found 298 OSA cases in PCOS women vs. 222 in controls, with incidence rates for OSA of 8.1 and 3.3 per 10,000 person years, respectively. Women with PCOS were at increased risk of developing OSA (Adjusted HR=2.26, 95% CI: 1.89 – 2.69, p<0.001), with similar HRs for normal weight, overweight and obese PCOS women.

Conclusions: Women with PCOS are at increased risk of developing OSA compared to control women irrespective of obesity. Considering the significant metabolic morbidity associated with OSA, clinicians should have a low threshold to test for OSA in women with PCOS. Whether OSA treatment has an impact on PCOS symptoms and outcomes needs to be examined.

Open access

Thang S Han, Nils Krone, Debbie S Willis, Gerard S Conway, Stefanie Hahner, D Aled Rees, Roland H Stimson, Brian R Walker, Wiebke Arlt, Richard J Ross and the United Kingdom Congenital adrenal Hyperplasia Adult Study Executive (CaHASE)

Context

Quality of life (QoL) has been variously reported as normal or impaired in adults with congenital adrenal hyperplasia (CAH). To explore the reasons for this discrepancy we investigated the relationship between QoL, glucocorticoid treatment and other health outcomes in CAH adults.

Methods

Cross-sectional analysis of 151 adults with 21-hydroxylase deficiency aged 18–69 years in whom QoL (assessed using the Short Form Health Survey), glucocorticoid regimen, anthropometric and metabolic measures were recorded. Relationships were examined between QoL, type of glucocorticoid (hydrocortisone, prednisolone and dexamethasone) and dose of glucocorticoid expressed as prednisolone dose equivalent (PreDEq). QoL was expressed as z-scores calculated from matched controls (14 430 subjects from UK population). Principal components analysis (PCA) was undertaken to identify clusters of associated clinical and biochemical features and the principal component (PC) scores used in regression analysis as predictor of QoL.

Results

QoL scores were associated with type of glucocorticoid treatment for vitality (P=0.002) and mental health (P=0.011), with higher z-scores indicating better QoL in patients on hydrocortisone monotherapy (P<0.05). QoL did not relate to PreDEq or mutation severity. PCA identified three PCs (PC1, disease control; PC2, adiposity and insulin resistance and PC3, blood pressure and mutations) that explained 61% of the variance in observed variables. Stepwise multiple regression analysis demonstrated that PC2, reflecting adiposity and insulin resistance (waist circumference, serum triglycerides, homeostasis model assessment of insulin resistance and HDL-cholesterol), related to QoL scores, specifically impaired physical functioning, bodily pain, general health, Physical Component Summary Score (P<0.001) and vitality (P=0.002).

Conclusions

Increased adiposity, insulin resistance and use of prednisolone or dexamethasone are associated with impaired QoL in adults with CAH. Intervention trials are required to establish whether choice of glucocorticoid treatment and/or weight loss can improve QoL in CAH adults.

Open access

Conor P Woods, Nicola Argese, Matthew Chapman, Christopher Boot, Rachel Webster, Vijay Dabhi, Ashley B Grossman, Andrew A Toogood, Wiebke Arlt, Paul M Stewart, Rachel K Crowley and Jeremy W Tomlinson

Context

Up to 3% of US and UK populations are prescribed glucocorticoids (GC). Suppression of the hypothalamo–pituitary–adrenal axis with the potential risk of adrenal crisis is a recognized complication of therapy. The 250 μg short Synacthen stimulation test (SST) is the most commonly used dynamic assessment to diagnose adrenal insufficiency. There are challenges to the use of the SST in routine clinical practice, including both the staff and time constraints and a significant recent increase in Synacthen cost.

Methods

We performed a retrospective analysis to determine the prevalence of adrenal suppression due to prescribed GCs and the utility of a morning serum cortisol for rapid assessment of adrenal reserve in the routine clinical setting.

Results

In total, 2773 patients underwent 3603 SSTs in a large secondary/tertiary centre between 2008 and 2013 and 17.9% (n=496) failed the SST. Of 404 patients taking oral, topical, intranasal or inhaled GC therapy for non-endocrine conditions, 33.2% (n=134) had a subnormal SST response. In patients taking inhaled GCs without additional GC therapy, 20.5% (34/166) failed an SST and suppression of adrenal function increased in a dose-dependent fashion. Using receiver operating characteristic curve analysis in patients currently taking inhaled GCs, a basal cortisol ≥348 nmol/l provided 100% specificity for passing the SST; a cortisol value <34 nmol/l had 100% sensitivity for SST failure. Using these cut-offs, 50% (n=83) of SSTs performed on patients prescribed inhaled GCs were unnecessary.

Conclusion

Adrenal suppression due to GC treatment, particularly inhaled GCs, is common. A basal serum cortisol concentration has utility in helping determine which patients should undergo dynamic assessment of adrenal function.

Open access

Jan Idkowiak, Yasir S Elhassan, Pascoe Mannion, Karen Smith, Rachel Webster, Vrinda Saraff, Timothy G Barrett, Nicholas J Shaw, Nils Krone, Renuka P Dias, Melanie Kershaw, Jeremy M Kirk, Wolfgang Högler, Ruth E Krone, Michael W O’Reilly and Wiebke Arlt

Objective

Androgen excess in childhood is a common presentation and may signify sinister underlying pathology. Data describing its patterns and severity are scarce, limiting the information available for clinical decision processes. Here, we examined the differential diagnostic value of serum DHEAS, androstenedione (A4) and testosterone in childhood androgen excess.

Design

Retrospective review of all children undergoing serum androgen measurement at a single center over 5 years.

Methods

Serum A4 and testosterone were measured by tandem mass spectrometry and DHEAS by immunoassay. Patients with at least one increased androgen underwent phenotyping by clinical notes review.

Results

In 487 children with simultaneous DHEAS, A4 and testosterone measurements, we identified 199 with androgen excess (140 pre- and 59 post-pubertal). Premature adrenarche (PA) was the most common pre-pubertal diagnosis (61%), characterized by DHEAS excess in 85%, while A4 and testosterone were only increased in 26 and 9% respectively. PCOS was diagnosed in 40% of post-pubertal subjects, presenting equally frequent with isolated excess of DHEAS (29%) or testosterone (25%) or increases in both A4 and testosterone (25%). CAH patients (6%) predominantly had A4 excess (86%); testosterone and DHEAS were increased in 50 and 33% respectively. Concentrations increased above the two-fold upper limit of normal were mostly observed in PA for serum DHEAS (>20-fold in the single case of adrenocortical carcinoma) and in CAH for serum androstenedione.

Conclusions

Patterns and severity of childhood androgen excess provide pointers to the underlying diagnosis and can be used to guide further investigations.