Pitfalls in the lab assessment of hypopituitarism.

The diagnostic approach to hypopituitarism involves many disciplines. Clinical symptoms rarely are specific. Imaging techniques are helpful but cannot prove the specific functional defects. Therefore, the definitive diagnosis of pituitary insufficiency is largely based on laboratory tests. However, also laboratory methods come with inherent limitations, and it is essential for the clinician to know and recognize typical pitfalls. Most factors potentially impairing the quality of hormone measurements are introduced in the preanalytical phase, i.e. before the hormones are measured by the laboratory. For example, the timing of blood drawing with respect to circadian rhythm, stress, and medication can have an influence on hormone concentrations. During the actual analysis of the hormones, cross-reactions with molecules present in the sample presenting the same or similar epitopes than the intended analyte may affect immunoassays. Interference can also come from heterophilic or human anti-animal antibodies. Unexpected problems can also be due to popular nutritional supplements which interfere with the measurement procedures. An important example in this respect is the interference from biotin. It became only clinically visible when the use of this vitamin became popular among patients. The extreme serum concentrations reached when patients take it as a supplement can lead to incorrect measurements in immunoassays employing the biotin-streptavidin system. To some extent, hormone analyses using liquid chromatography mass spectrometry (LCMS) can overcome problems, although availability and cost-effectiveness of this method still imposes restrictions. In the post-analytical phase, appropriateness of reference intervals and cut-offs with respect to the specific analytical method used is of outmost importance. Furthermore, for interpretation, additional biological and pharmacological factors like BMI, age and concomitant diseases must be considered to avoid misinterpretation of the measured concentrations. It is important for the clinician and the laboratory to recognize when one or more laboratory values do not match the clinical picture. In an interdisciplinary approach, the search for the underlying cause should be initiated.

Opposing effects of cannabidiol in patient-derived neuroendocrine tumor, pheochromocytoma/paraganglioma primary cultures.

CONTEXT: Treatment options for advanced neuroendocrine tumors (NETs), pheochromocytomas and paragangliomas (together PPGLs) are still limited. In recent years, anti-tumor effects of cannabinoids have been reported; however, there are only very limited data available in NETs or PPGLs. OBJECTIVE: Investigation of the effects of cannabidiol (CBD) on patient-derived human NET/PPGL primary cultures and on NET/PPGL cell lines. METHODS: We established primary cultures derived from 46 different patients with PPGLs (n = 35) or NETs (n = 11) who underwent tumor resection at two centers. Treatment of patient primary cultures with clinically relevant doses (5 µM) and slightly higher doses (10 µM) of CBD was performed. RESULTS: We found opposing effects of 5 µM CBD: significant anti-tumor effects in 5/35 (14%) and significant tumor-promoting effects in 6/35 (17%) of PPGL primary cultures. In terms of anti-tumor effects, cluster 2-related PPGLs showed significantly stronger responsivity to CBD compared to cluster 1-related PPGLs (p = 0.042). Of the cluster 2-related tumors, NF1 PPGLs showed strongest responsivity (4/5 PPGL primary cultures with a significant decrease in cell viability were NF1-mutated). We also found opposing effects of 10 µM CBD in PPGLs and NETs: significant anti-tumor effects in 9/33 of PPGL (27%) and 3/11 of NET (27%) primary cultures, significant tumor-promoting effects in 6/33 of PPGL (18%) and 2/11 of NET (18%) primary cultures. CONCLUSIONS: We suggest a potential novel treatment option for some NETs/PPGLs, but also provide evidence for caution when applying cannabinoids as supportive therapy for pain or appetite management to cancer patients, and possibly as health supplements.

Growth hormone treatment in aged patients with comorbidities: A systematic review.

OBJECTIVE: Hormonal substitution with growth hormone in aged patients remains a debated research topic and is rarely initiated in clinical practice. This reluctance may originate from concerns about adverse effects and the uncritical use as an anti-aging agent. Nevertheless, beneficial effects for selected patients suffering from certain acute and chronic illnesses could justify its use at an advanced age. This systematic review analyzes randomized controlled studies of GH interventions in older patients with different comorbidities to assess both, beneficial and harmful effects. DESIGN: A systematic search strategy was implemented to identify relevant studies from PubMed, MEDLINE, and The Cochrane Library. INCLUSION CRITERIA: participants aged over 65 years, randomized controlled trials involving human growth hormone (GH) and presence of at least one additional comorbidity independent of a flawed somatotropic axis. RESULTS: The eight eligible studies encompassed various comorbidities including osteoporosis, frailty, chronic heart failure, hip fracture, amyotrophic lateral sclerosis and hemodialysis. Outcomes varied, including changes in body composition, physical performance, strength, bone mineral density, cardiovascular parameters, quality of life and housing situation. Study protocols differed greatly in GH application frequency (daily, 2nd day or 3×/week), doses (0.41 mg-2.6 mg; mean 1.3 mg per 60 kg patient) and duration (1-12 months; mean 7 months). Mild dose-related side effects were reported, alongside noticeable positive impacts particularly on body composition, functionality, and quality of life. CONCLUSION: Despite limited evidence, GH treatment might offer diverse benefits with few adverse effects. Further research with IGF-I dependent indication and clear outcomes, incorporating IGF-I dependent GH titration in older adults is warranted.

Management of pasireotide-induced hyperglycemia in patients with acromegaly: An experts' consensus statement.

Pasireotide is a somatostatin analogue for the treatment of acromegaly, a chronic condition caused by excess growth hormone. Despite the therapeutic benefits of pasireotide as a second-line treatment for inadequately controlled acromegaly, a major concern is its hyperglycemic side-effect. Here, we provide guidance on how to select appropriate patients with acromegaly for treatment with pasireotide. We summarize baseline characteristics of patients at high risk for pasireotide-associated hyperglycemia and recommend a monitoring strategy based on the risk profile. Self-monitoring of blood glucose levels (SMBG), measurements of fasting plasma glucose (FPG), postprandial plasma glucose (PPG) and regular HbA1c measurements are the foundation of our proposed monitoring approach. The pathophysiology of pasireotide-induced hyperglycemia involves decreased secretion of the incretin hormones GIP (glucose-dependent insulinotropic polypeptide) and GLP-1 (glucagon-like peptide-1). Our expert recommendations address the specific pathophysiology of pasireotide-induced hyperglycemia by recommending the incretin-based therapeutics dipeptidyl peptidase-4 inhibitors (DPP-4i) and glucagon-like peptide-1 receptor agonists (GLP-1 RA) in all appropriate patients as an alternative to first-line monotherapy with metformin. Furthermore, we emphasize the importance of adequate control of acromegaly, excellent diabetes education, nutrition and lifestyle guidance and advise to consult expert diabetologists in case of uncertainty in the management of patients with hyperglycemia under pasireotide.

Age- and sex-adjusted reference intervals for steroid hormones measured by liquid chromatography-tandem mass spectrometry using a widely available kit.

Objective: Measurements utilizing commercially available sets of reagents for determination of steroid hormone profiles by liquid chromatography-tandem mass spectrometry (LC-MS/MS) have become increasingly important for routine laboratories. However, method-specific publications of reference intervals obtained from sufficiently large studies are often missing. Methods: After validation of performance characteristics, a widely available kit for steroid analysis by LC-MS/MS was used to measure concentrations of 15 endogenous steroids (aldosterone, cortisol, cortisone, corticosterone, 11-deoxycortisol, 21-deoxycortisol, dehydroepiandrosterone sulfate, estradiol, testosterone, androstenedione, dihydrotestosterone, dehydroepiandrosterone, 17-hydroxyprogesterone, 11-deoxycorticosterone, progesterone) in more than 500 blood samples from a population-based study. While randomly selected from a larger cohort, the samples equally represented both sexes and covered a wide range of adult age groups. Age- and sex-specific reference intervals were calculated, and correlation with BMI was assessed. Results: Performance characteristics of the assay matched expectations for 9 of 15 steroids. For most of them, reference intervals obtained from our study population were comparable to those reported by others, with age and sex being the major determinants. A sex-specific correlation with BMI was found for seven steroids. We identified limitations regarding sensitivity of the method for quantification of progesterone in males and postmenopausal females. Concentrations of aldosterone, 21-deoxycortisol, estradiol, 11-deoxycorticosterone, and dihydrotestosterone could not be quantified in a large percentage of samples. Conclusions: The reference intervals for nine steroids will support meaningful interpretation for steroid profiles as measured by a widely used kit for LC-MS/MS-based quantification. Laboratories using such kits must be aware of potential limitations in sensitivity for some steroids included in the profile. Significance Statement: Quantification of steroid hormones is a cornerstone for diagnosis of several diseases. Commonly used immunoassays have limitations in specificity. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) is a promising alternative, particularly if methods are harmonized across laboratories. The use of kits from commercial suppliers might support this. Clinical interpretation of steroid concentrations requires availability of appropriate reference intervals (RIs), but studies on RIs reported in the literature differ in preanalytical and analytical procedures. Here, we provide RIs for steroids measured by a widely available kit under preanalytical conditions mirroring common clinical practice. Such RIs might facilitate interpretation for those using the same method and comparable conditions in clinical routine.

A combined top-down and bottom-up LC-HRMS/MS method for the quantification of human growth hormone in plasma and serum.

OBJECTIVE: The precise and accurate quantification of human growth hormone (GH) in plasma/ serum is crucial for the diagnosis and treatment of diseases like GH deficiency or acromegaly. However, the ligand-binding assays (LBAs) currently used for routine testing show considerable methodological variability. Here, we present a complementary, combined top-down and bottom-up LC-MS-based method to quantify (intact) GH in plasma and serum, which concurrently provides a basis for a MS-based analysis of GH in doping controls. DESIGN: Extraction of GH from plasma/ serum was accomplished by protein precipitation, followed by an immunocapture step using protein A-coupled magnetic beads and a polyclonal anti-GH antibody. The intact protein was subsequently analyzed top-down on a 2D-LC-HRMS/MS system. In addition, sample extracts were digested with trypsin and analyzed for signal peptides corresponding to 'total', 22 kDa and 20 kDa GH (bottom-up). Both assays were validated according to current guidelines and compared to the GH isoform differential immunoassay used in routine doping control analysis. GH concentrations in serum samples of healthy adults, patients with acromegaly, and in samples obtained after administration of recombinant GH were analyzed as proof-of-principle. RESULTS: The intact monomeric 22 kDa isoform of GH was selectively quantified in a representative working range of 0.5 to 10 ng/ml by top-down LC-HRMS/MS. Subsequent bottom-up analysis provided additional data on 'total' and 20 kDa GH. Top-down and bottom-up assay results for the 22 kDa isoform correlated well with the corresponding immunoassay results (R2 > 0.95). For a possible application of the method in an anti-doping context, the ratio between 22 kDa and 'total' GH was evaluated, indicating differences between the various donor groups, but only with limited significance. CONCLUSION: The top-down and bottom-up LC-HRMS/MS method developed here presents a valuable tool for the quantification of GH in plasma/ serum complementary to established LBAs used at present in clinical measurements. Albeit the examination of the GH isoform proportions by the LC-MS method does not yet allow for the assessment of GH abuse, the obtained findings provide an important basis to enable LC-MS-based GH analysis of doping control samples in the future.

Can Growth Hormone Lead to a Faster Recovery from Guillain-Barré Syndrome? Case Report of the First Therapeutic Use in One Patient.

Although the prognosis in Guillain-Barré syndrome (GBS) is generally good, protracted and incomplete courses of recovery can be a heavy burden. Animal studies suggest growth hormone (GH) treatment could stimulate myelin repair and thus accelerate functional recovery in acute polyneuropathy. We report on the first use of GH in GBS. Our objective was to monitor safety and tolerability as well as to evaluate the effect of an off-label GH therapy during recovery from GBS in 1 patient. A 28-year-old male with flaccid tetraparesis caused by pure motor GBS was treated off-label with GH (1 mg/day) for 10 weeks. Muscle strength was measured regularly before, during, and after the treatment over a total span of 330 days. Serum levels of IGF-I were assessed before, during, and after GH treatment. Changes in strength gain were used as the main parameter of efficacy. No side effects of GH treatment were observed. Serum IGF-I increased from 177 ng/mL at baseline to an average of 342 ng/mL (normal range 78-270 ng/mL) during treatment. Prior to GH administration, strength (R2 = 0.99, p < 0.01) was associated with time, representing the natural course of recovery. During GH treatment, the slope of strength gain increased (Glass' ∆ = 1.08, p < 0.01). The association between alterations of strength gain and IGF-I serum levels reached trend level (R2 = 0.36, p = 0.09). In this single case, GH treatment seemed to be associated with faster muscular strength gain. Controlled studies are needed in order to establish GH as a potential therapeutic approach in motor GBS.

Characterization of dominant-negative growth hormone receptor variants reveals a potential therapeutic target for short stature.

OBJECTIVE: Growth hormone insensitivity (GHI) encompasses growth restriction, normal/elevated growth hormone (GH), and low insulin-like growth factor I (IGF1). "Nonclassical" GHI is poorly characterized and is rarely caused by heterozygous dominant-negative (DN) variants located in the intracellular or transmembrane domains of the GH receptor (GHR). We sought to determine the molecular mechanisms underpinning the growth restriction in 2 GHI cases. METHODS AND DESIGN: A custom-made genetic investigative pipeline was exploited to identify the genetic cause of growth restriction in patients with GHI. Nanoluc binary technology (NanoBiT), in vitro splicing assays, western blotting, and flow cytometry, characterized the novel GHR variants. RESULTS: Novel heterozygous GHR variants were identified in 2 unrelated patients with GHI. In vitro splicing assays indicated both variants activated the same alternative splice acceptor site resulting in aberrant splicing and exclusion of 26 base pairs of GHR exon 9. The GHR variants produced truncated receptors and impaired GH-induced GHR signaling. NanoBiT complementation and flow cytometry showed increased cell surface expression of variant GHR homo/heterodimers compared to wild-type (WT) homodimers and increased recombinant human GH binding to variant GHR homo/heterodimers and GH binding protein (GHBP) cleaved from the variant GHRs. The findings demonstrated increased variant GHR dimers and GHBP with resultant GH sequestration. CONCLUSION: We identified and characterized 2 novel, naturally occurring truncated GHR gene variants. Intriguingly, these DN GHR variants act via the same cryptic splice acceptor site, highlighting impairing GH binding to excess GHBP as a potential therapeutic approach.

Low-grade inflammation during the glucocorticoid withdrawal phase in patients with Cushing's syndrome.

IMPORTANCE: Endogenous Cushing's syndrome (CS) leads to profound immunosuppression. Successful surgery induces biochemical remission and reversal of immunosuppression, which is characterized by clinical signs of glucocorticoid withdrawal and associated with increased susceptibility to infections and thromboembolic complications. OBJECTIVE: We hypothesized that the glucocorticoid withdrawal phase is characterized by low-grade inflammation that may be related to patient-relevant outcomes. SETTING: In this retrospective observational study, we analyzed longitudinal data from 80 patients with CS prospectively enrolled in the German Cushing's registry between 2012 and 2021. All enrolled patients underwent successful surgery. In a second step, a case-control study was performed in 25 of the patients with age-, gender-, and body mass index-matched control patients in whom hypercortisolism was excluded. Analyses included the inflammatory markers C-reactive protein and interleukin-6, as well as body composition, muscle function testing, and quality-of-life questionnaires. The patients were studied during active CS and in the postoperative remission phase 1, 3, 6, 12, and 24 months after surgery. RESULTS: Compared with the preoperative phase and matched controls, patients with CS had increased systemic inflammatory markers in the early remission phase. One month following surgery, median (interquartile range) C-reactive protein was 0.48 mg dL-1 (0.14-0.90) vs 0.10 mg dL-1 (0.06-0.39) during active CS (P ≤ .001). Similarly, interleukin-6 1 month after surgery was 7.2 pg mL-1 (3.3-11.7) vs 1.7 pg mL-1 (1.5-2.5) during active CS (P ≤ .001). Obesity and hemoglobin A1c (HbA1c) were associated with increased inflammation levels. This proinflammatory state lasted until 1 year following surgery. Moreover, inflammatory markers during early remission showed an inverse correlation with long-term muscle function. CONCLUSIONS: The glucocorticoid withdrawal phase is associated with a low-grade inflammatory state, which is particularly pronounced in obese and hyperglycemic patients and related to lower muscle function.

Delving into Acromegaly.

Acromegaly is a rare and disabling disease with some distinct and striking clinical features that have fascinated (and frightened) laypeople and medical experts alike throughout history [...].

Health-related quality of life (EuroQol 5D-5L) in patients with autoimmunity in the context of immunotherapy: A large dataset comprising cancer patients after cessation of checkpoint inhibitor therapy and patients with autoimmune diseases.

This dataset contains demographic, clinical, and health-related quality of life (HRQoL) data from 2905 patients including 200 cancer patients after immune checkpoint inhibitor (ICI) cessation and 2705 patients with a wide variety of autoimmune diseases. Within this multicenter, cross-sectional survey study data were collected questionnaire-based in cancer patients (ICI-patients) ≥ 18 years of age who had received at least one dose of ICI with ≥ 12 weeks since ICI discontinuation. Patients with autoimmune diseases (AI-patients) were ≥ 18 years, had at least one autoimmune disease and had never received ICI. ICI-patients were recruited in three skin cancer centers and via support groups. AI-patients were recruited in an outpatient clinic for internal medicine and via support groups. Specific questionnaires for ICI-patients/AI-patients were provided paper-based for patients from outpatient clinics and online for patients from support groups. Both questionnaires contained sections with demographic information, clinical data, and the standardized patient-reported outcome measure EuroQol 5D-5L (EQ-5D-5L) to assess HRQoL. Clinical data focused on autoimmunity and therapy of autoimmunity in (1) ICI-patients referring to particularly persistent immune-related adverse events (persistent irAEs) and in (2) AI-patients referring to respective autoimmune diseases. Additionally, specific items on cancer and cancer therapy were included in ICI-patients, and AI-patients were asked about the presence of acute exacerbations of autoimmune diseases. This dataset contains the raw data for ICI-patients and AI-patients, analyzed data on patient demographics, clinical characteristics and HRQoL scores among ICI-patients with/without persistent irAEs and among AI-patients. The data provide a basis for further investigations within the cohort of ICI-patients after ICI cessation and/or for AI-patients with different autoimmune diseases with regard to HRQoL, autoimmunity and therapy of autoimmunity.

Persistent immune-related adverse events after cessation of checkpoint inhibitor therapy: Prevalence and impact on patients' health-related quality of life.

BACKGROUND: Immune checkpoint inhibitors (ICIs) may induce persistent immune-related adverse events (irAEs). We investigated persistent irAEs and implications on patients' lives compared to non-ICI-induced autoimmune diseases (AIs). METHODS: The multicentre, cross-sectional study comprised 200 patients with cancer ≥12 weeks after ICI cessation (ICI-patients) and 2705 patients with AIs (AI-patients), recruited in German outpatient clinics and support groups. The prevalence of persistent irAEs subdivided in long-term (12 weeks to <12 months) and chronic irAEs (≥12 months) since ICI discontinuation, health-related quality of life (HRQoL) using the EuroQol 5D-5L (EQ-Index/VAS score), and burden of autoimmune symptoms and respective therapies were assessed. RESULTS: Long-term/chronic irAEs occurred in 51.9%/35.5% of outpatient ICI-patients, including arthralgia (16.7%/16.1%), myalgia (13.0%/14.0%), hypothyroidism (11.1%/10.8%), xerostomia (7.4%/8.6%), vitiligo (13.0%/7.5%) and hypophysitis (9.3%/7.5%). ICI-patients with long-term/chronic irAEs reported clinically significantly reduced HRQoL compared to ICI-patients without long-term/chronic irAEs (EQ-Index score: 0.767/0.752 versus 0.920/0.923, p < 0.001/0.001; EQ-VAS score: 52.2/52.0 versus 63.6/74.7, p =/< 0.040/0.001). Multiple linear regression analyses confirmed clinically significant reductions in HRQoL scores by chronic irAEs (EQ-Index/VAS score: -0.163/-23.4, p < 0.001/0.001). HRQoL, burden of autoimmune symptoms and burden of respective therapies in ICI-patients with chronic irAEs were similar to AI-patients with non-exacerbated AIs. Patients with chronic irAEs felt inadequately informed about side-effects compared to patients without chronic irAEs (p < 0.001). CONCLUSION: Persistent irAEs impose a significant burden on patients after ICI cessation. Especially in early tumour stages, risk-benefit ratios must be carefully evaluated, and patients need to be informed about potential long-term sequelae.

11-Oxygenated C19 steroids are the predominant androgens responsible for hyperandrogenemia in Cushing's disease.

Background: Symptoms of hyperandrogenism are common in patients with Cushing's disease (CD), yet they are not sufficiently explained by androgen concentrations. In this study, we analyzed the contribution of 11-oxygenated C19 steroids (11oxC19) to hyperandrogenemia in female patients with CD. Methods: We assessed saliva day profiles in females with CD pre (n = 23) and post (n = 13) successful transsphenoidal surgery, 26 female controls, 5 females with CD treated with metyrapone and 5 treated with osilodrostat for cortisol, cortisone, androstenedione (A4), 11-hydroxyandrostenedione (11OHA4), testosterone (TS), 11-ketotestosterone (11KT), as well as metabolites of classic and 11-oxygenated androgens in 24-h urine. In addition, morning baseline levels of gonadotropins and estradiol, sex hormone-binding globulin, cortisol and dehydroepiandrosterone sulfate (DHEAS) in serum and adrenocorticotrophic hormone in plasma in patients and controls were investigated. Results: Treatment-naïve females with CD showed a significantly elevated area under the curve of 11OHA4 and 11KT in saliva throughout the day compared to controls (11OHA4 mean rank difference (mrd) 18.13, P = 0.0002; 11KT mrd 17.42; P = 0.0005), whereas A4, TS and DHEAS were comparable to controls. Gonadotropin concentrations were normal in all patients with CD. After transsphenoidal surgery, 11oxC19 and their metabolites dropped significantly in saliva (11OHA4 P < 0.0001; 11KT P = 0.0010) and urine (11-oxo-androsterone P = 0.0011; 11-hydroxy-androsterone P < 0.0001), treatment with osilodrostat and metyrapone efficaciously blocked 11oxC19 synthesis. Conclusion: Hyperandrogenemia in CD is predominantly caused by excess of 11oxC19 steroids.

Differences in the Distribution of IGF-I Concentrations Between European and US Populations.

Context: Method-specific reference intervals (RIs) determine utility of IGF-I as a biomarker in GH-related diseases. Differences between populations might affect applicability of RIs. Objective: To compare population-specific RIs derived from IGF-I routine testing in laboratories in the United States and Europe using the same assay. Design and setting: Uncensored routine IGF-I testing results generated over 5 years in 4 accredited laboratories (US, n = 778 173 males/710 752 females; Europe, n = 23 220 males/40 183 females). Main outcome measures: Construction of RIs by indirect statistical methods designed to use routine testing data (modified Hoffmann approach). Comparison to published RIs, between the US and Europe, and between regions in the United States with lower and higher mean body mass indexes (BMIs). Results: Lower limits (LLs) of RIs calculated from all routine data sets do not differ from the published LLs. The same is true for upper limits (ULs) calculated from European routine data. ULs derived from US routine data are significantly higher (children, 10-18 years [mean, %]: boys + 149.3 ng/mL [+34.6%]; girls + 94.9 ng/mL [+19.8%]); adults (19-95 years: males + 45 ng/mL [+20.3%]; and females + 29.7 ng/mL [+13.8%]). Average IGF-I is higher in samples from Colorado (lower mean BMI) compared with Alabama (P < 0.0001), although the difference is smaller than between each of them and Europe. Conclusions: We provide evidence that in large datasets from the same population, direct sampling and the indirect Hoffmann approach provide comparable RIs. Although LLs are comparable between Europe and the United States, the UL is significantly higher in the United States. We suggest use of adapted RIs for the United States.

Altered Circulating Leptin, hGH, and IGF-I in Prediabetes and Screening-Diagnosed T2DM Unrelated to Metabolic Syndrome in Women Post Gestational Diabetes.

Recently, we proposed two pathophysiologic subtypes of type 2 diabetes mellitus (T2DM), one related and one unrelated to metabolic syndrome. To begin to understand the pathophysiology of the subtype unrelated to metabolic syndrome, we now measured selected hormones and signaling molecules in affected individuals. In this cross-sectional analysis, we examined 138 women out of the monocenter, post gestational diabetes study PPSDiab. Of these women, 73 had prediabetes or screening-diagnosed T2DM, 40 related to metabolic syndrome and 33 unrelated. The remaining 65 women were normoglycemic controls. Our analysis included medical history, anthropometrics, oral glucose tolerance testing, laboratory chemistry, and cardiopulmonary exercise testing. In addition, plasma proinsulin/insulin ratio, growth hormone (hGH) nadir during oral glucose tolerance testing, Insulin-like Growth Factor I (IGF-I), Leptin, Resistin, Adiponectin, Fetuin-a, FGF21, and myostatin were measured. Compared to controls, women with prediabetes or screening-diagnosed T2DM unrelated to metabolic syndrome depicted higher plasma Leptin [10.47(6.6-14.57) vs. 5.52(3.15-10.02); p<0.0001] and IGF-I [193.01(171.00-213.30) vs. 167.97(138.77-200.64); p=0.0008], as well as a lower hGH nadir [0.07(0.05-0.15) vs. 0.14(0.08-0.22; p<0.0001]. These differences were independent of body adiposity. Women with prediabetes or T2DM related to metabolic syndrome, in comparison to controls, displayed elevated Leptin, Fetuin-a, and FGF21, as well as reduced Adiponectin and hGH nadir. Based on our study, altered Leptin and hGH/IGF-I signaling could potentially contribute to the pathophysiology of prediabetes and T2DM unrelated to metabolic syndrome. Further mechanistic investigations of these signaling pathways in the context of lean T2DM are necessary to test causal relationships.

Diurnal Salivary Cortisol Profiles in Patients with Cushing's Syndrome.

BACKGROUND: Quantification of salivary cortisol is one of the highly sensitive and specific screening parameters for Cushing's syndrome (CS). However, only late-night salivary cortisol is part of the standard screening procedure. In this study, we aimed to analyze salivary cortisol day profiles in patients with different types of CS to test whether specific patterns might be relevant for diagnosis and subtyping. MATERIAL AND METHODS: Among 428 patients including those with confirmed Cushing's syndrome (N=111, of those 75 with Cushing's disease, 27 patients with adrenal CS and nine patients with ectopic CS), autonomous cortisol secretion (N=39) or exclusion of CS (control group, N=278) salivary cortisol was measured five times a day. RESULTS: At each of the five time points, salivary cortisol was significantly higher in patients with CS compared to the control group (p≤0.001). Using the entire profile instead of one single salivary cortisol at 11 p.m. improved diagnostic accuracy (85 vs. 91%) slightly. Patients with ACTH-dependent CS had higher salivary cortisol levels than patients with adrenal CS. Also, morning cortisol was significantly higher in patients with ectopic CS than in patients with Cushing's disease (p=0.04). Nevertheless, there was a strong overlap between diurnal profiles, and the diagnostic yield for subtyping was low. DISCUSSION: The study results show that using diurnal salivary cortisol profiles for CS diagnosis results in a limited increase in diagnostic accuracy. With significant differences between Cushing subtypes, cortisol profiles are not useful in everyday clinical practice for subtyping of CS.

Differences between immunotherapy-induced and primary hypophysitis-a multicenter retrospective study.

OBJECTIVE: Immune checkpoint inhibitors can cause various immune-related adverse events including secondary hypophysitis. We compared clinical characteristics of immunotherapy-induced hypophysitis (IIH) and primary hypophysitis (PH) DESIGN: Retrospective multicenter cohort study including 56 patients with IIH and 60 patients with PH. METHODS: All patients underwent extensive endocrine testing. Data on age, gender, symptoms, endocrine dysfunction, MRI, immunotherapeutic agents and autoimmune diseases were collected. RESULTS: Median time of follow-up was 18 months in IIH and 69 months in PH. The median time from initiation of immunotherapy to IIH diagnosis was 3 months. IIH affected males more frequently than PH (p < 0.001) and led to more impaired pituitary axes in males (p < 0.001). The distribution of deficient adenohypophysial axes was comparable between both entities, however, central hypocortisolism was more frequent (p < 0.001) and diabetes insipidus considerably less frequent in IIH (p < 0.001). Symptoms were similar except that visual impairment occurred more rarely in IIH (p < 0.001). 20 % of IIH patients reported no symptoms at all. Regarding MRI, pituitary stalk thickening was less frequent in IIH (p = 0.009). Concomitant autoimmune diseases were more prevalent in PH patients before the diagnosis of hypophysitis (p = 0.003) and more frequent in IIH during follow-up (p = 0.002). CONCLUSIONS: Clinically, IIH and PH present with similar symptoms. Diabetes insipidus very rarely occurs in IIH. Central hypocortisolism, in contrast, is a typical feature of IIH. Preexisting autoimmunity seems not to be indicative of developing IIH.

Metformin and Bone Metabolism in Endogenous Glucocorticoid Excess: An Exploratory Study.

Context: Glucocorticoid excess exhibits multiple detrimental effects by its catabolic properties. Metformin was recently suggested to protect from adverse metabolic side-effects of glucocorticoid treatment. Whether metformin is beneficial in patients with endogenous glucocorticoid excess has not been clarified. Objective: To evaluate the phenotype in patients with endogenous Cushing's syndrome (CS) treated with metformin at the time of diagnosis. Patients and Methods: As part of the German Cushing's Registry we selected from our prospective cohort of 96 patients all 10 patients who had been on pre-existing metformin treatment at time of diagnosis (CS-MET). These 10 patients were matched for age, sex and BMI with 16 patients without metformin treatment (CS-NOMET). All patients had florid CS at time of diagnosis. We analyzed body composition, metabolic parameters, bone mineral density and bone remodeling markers, muscle function and quality of life. Results: As expected, diabetes was more prevalent in the CS-MET group, and HbA1c was higher. In terms of comorbidities and the degree of hypercortisolism, the two groups were comparable. We did not observe differences in terms of muscle function or body composition. In contrast, bone mineral density in metformin-treated patients was superior to the CS-NOMET group at time of diagnosis (median T-Score -0.8 versus -1.4, p = 0.030). CS-MET patients showed decreased ß-CTX levels at baseline (p = 0.041), suggesting reduced bone resorption under metformin treatment during glucocorticoid excess. Conclusion: This retrospective cohort study supports potential protective effects of metformin in patients with endogenous glucocorticoid excess, in particular on bone metabolism.

Growth Hormone Receptor (GHR) 6Ω Pseudoexon Activation: a Novel Cause of Severe Growth Hormone Insensitivity.

CONTEXT: Severe forms of growth hormone insensitivity (GHI) are characterized by extreme short stature, dysmorphism, and metabolic anomalies. OBJECTIVE: This work aims to identify the genetic cause of growth failure in 3 "classical" GHI individuals. METHODS: A novel intronic growth hormone receptor gene (GHR) variant was identified, and in vitro splicing assays confirmed aberrant splicing. A 6Ω pseudoexon GHR vector and patient fibroblast analysis assessed the consequences of the novel pseudoexon inclusion and the impact on GHR function. RESULTS: We identified a novel homozygous intronic GHR variant (g.5:42700940T > G, c.618+836T > G), 44 bp downstream of the previously recognized intronic 6Ψ GHR pseudoexon mutation in the index patient. Two siblings also harbored the novel intronic 6Ω pseudoexon GHR variant in compound heterozygosity with the known GHR c.181C > T (R43X) mutation. In vitro splicing analysis confirmed inclusion of a 151-bp mutant 6Ω pseudoexon not identified in wild-type constructs. Inclusion of the 6Ω pseudoexon causes a frameshift resulting in a nonfunctional truncated GHR lacking the transmembrane and intracellular domains. The truncated 6Ω pseudoexon protein demonstrated extracellular accumulation and diminished activation of STAT5B signaling following GH stimulation. CONCLUSION: Novel GHR 6Ω pseudoexon inclusion results in loss of GHR function consistent with a severe GHI phenotype. This represents a novel mechanism of Laron syndrome and is the first deep intronic variant identified causing severe postnatal growth failure. The 2 kindreds originate from the same town in Campania, Southern Italy, implying common ancestry. Our findings highlight the importance of studying variation in deep intronic regions as a cause of monogenic disorders.

Growth Hormone Receptor (Ghr) 6ω Pseudoexon Activation: A Novel Cause Of Severe Growth Hormone Insensitivity (Ghi).

CONTEXT: Severe forms of Growth Hormone Insensitivity (GHI) are characterized by extreme short stature, dysmorphism and metabolic anomalies. OBJECTIVE: Identification of the genetic cause of growth failure in 3 'classical' GHI subjects. DESIGN: A novel intronic GHR variant was identified, and in vitro splicing assays confirmed aberrant splicing. A 6Ω pseudoexon GHR vector and patient fibroblast analysis assessed the consequences of the novel pseudoexon inclusion and the impact on GHR function. RESULTS: We identified a novel homozygous intronic GHR variant (g.5:42700940T>G, c.618 + 836T> G), 44bp downstream of the previously recognized intronic 6Ψ GHR pseudoexon mutation in the index patient. Two siblings also harbored the novel intronic 6Ω pseudoexon GHR variant in compound heterozygosity with the known GHR c.181C>T (R43X) mutation. In vitro splicing analysis confirmed inclusion of a 151bp mutant 6Ω pseudoexon not identified in wild-type constructs. Inclusion of the 6Ω pseudoexon causes a frameshift resulting in a non-functional truncated GHR lacking the transmembrane and intracellular domains. The truncated 6Ω pseudoexon protein demonstrated extracellular accumulation and diminished activation of STAT5B signaling following growth hormone stimulation. CONCLUSION: Novel GHR 6Ω pseudoexon inclusion results in loss of GHR function consistent with a severe GHI phenotype. This represents a novel mechanism of Laron syndrome and is the first deep intronic variant identified causing severe postnatal growth failure. The 2 kindreds originate from the same town in Campania, Southern Italy, implying common ancestry. Our findings highlight the importance of studying variation in deep intronic regions as a cause of monogenic disorders.