Construction of a predictive scoring system as a guide to screening and confirmation of the diagnosis of primary aldosteronism

BACKGROUND

Primary aldosteronism (PA) is the most frequent cause of secondary hypertension. In Southern Thailand, the aldosterone-renin ratio (ARR) is only available within a small number of tertiary centres, necessitating need for a simple clinical assessment to determine the requirement for ARR.

OBJECTIVE

This study aimed to identify predictive factors for the diagnosis of PA and generate a predictive scoring system (PSS) for use in screening and diagnosis of PA.

PATIENTS AND METHODS

A total of 420 patients aged >15 years with paired plasma aldosterone concentration and plasma renin activity values allowing calculation of ARR were identified from the electronic hospital database between 2011 and 2016.

RESULTS

The overall prevalence of PA was 16.7% (range; adrenal incidentaloma 5.6% to hypokalaemia 30%). Predictive factors for diagnosis of PA were as follows: age <60 years, BMI < 25 kg/m² , presence of diabetes, ≥3 antihypertensive agents, serum sodium ≥ 141 mmol/L and serum potassium < 3.5 mmol/L. A predictive scoring system (PSS) (range -2 to 13) was generated by the coefficients of the variables with ROC curve AUC 0.87 [95% CI: 0.83-0.91]. Using the PSS, a total score <4 provided a robust negative predictive value (sensitivity, 0.97; specificity, 0.48; NPV, 0.99; PPV, 0.27) for PA. In patients at high risk of PA (PAC > 15 ng/dL and PRA < 1.0 ng/mL/hr), a PSS score > 9 had specificity and PPV of 100%, essentially confirming PA in these individuals.

CONCLUSION

The proposed PSS for PA will enable more focused and cost-effective use of ARR screening and confirmatory testing. In our cohort, 40% and 42% of patients would not require ARR screening or confirmatory tests, respectively.

Use of peripheral plasma aldosterone concentration and response to ACTH during simultaneous bilateral adrenal veins sampling to predict the source of aldosterone secretion in primary aldosteronism

CONTEXT

Previous studies suggested that plasma aldosterone (PAC) response to ACTH stimulation could predict the subtypes of primary aldosteronism (PA) and avoid adrenal venous sampling (AVS).

OBJECTIVE

Assess the usefulness of peripheral (P) PAC response to ACTH stimulation during AVS to identify the source of aldosterone in patients with PA.

METHODS

Two hundred and fifteen patients were assigned to four different lateralization ratio (LR) groups based on different combinations of basal (≥ or <2) and post-ACTH LR (≥ or <4). The P vein parameters analysed included as follows: mean basal PAC, maximal PAC (PAC_max ), and PAC/C ratio (PAC_max /C), PAC absolute increase, PAC relative increase following ACTH bolus (250 mcg IV) and maximal variation of PAC/C ratio between post-ACTH and basal measures.

RESULTS

Mean basal PAC was significantly higher in group 1 (basal LR > 2 and post-ACTH > 4) than in group 2 (basal LR > 2, post-ACTH < 4) or group 4 (basal LR < 2 post-ACTH < 4) (P < .001). PAC_max , PAC_max /C and PAC absolute increase following ACTH were higher in group 1 than the others (P < .017). Using receiver operating characteristic (ROC) curves analysis of groups 1 and 4, best AUC were obtained with mean basal PAC (AUC: 0.757 95% IC: 0.653-0.861), PAC_max (AUC: 0.753 95% IC: 0.646-0.860) and PAC_max /C (AUC: 0.750 95% IC: 0.646-0.853).

CONCLUSION

P mean basal PAC and PAC_max and PAC_max /C are higher in basal and ACTH lateralized PA than in other groups. Peripheral PAC cut-off values fail to adequately distinguish all groups and cannot replace the requirement to conduct AVS.

Cushing's syndrome: Treatment and new therapeutic approaches

Overt Cushing's syndrome is a severe condition responsible for multiple comorbidities and increased mortality. Effective treatment is essential to reduce mortality, improve comorbidities and long-term quality of life. Surgical resection of the causal lesion(s) is generally the first-line and most effective treatment to normalize cortisol secretion. Adjunctive symptomatic treatments of co-morbidities are often necessary both during the active phase of the disease and for persisting co-morbidities after cessation of hypercortisolism. Second-line treatments include various pharmacological treatments, bilateral adrenalectomy, and radiotherapy of corticotroph tumors. The choice of these treatments is complex, must be performed in a multidisciplinary expert team to be individualized for each patient, and use a shared decision-making approach.

Cushing's syndrome - Disease monitoring: Recurrence, surveillance with biomarkers or imaging studies

Pituitary surgery is the first-line treatment for patients with Cushing's disease. For patients who are not considered candidates for pituitary surgery, pituitary radiation and bilateral adrenalectomy are further treatment alternatives. Not all patients are cured with pituitary surgery, and a substantial number of patients develop recurrence, sometimes many years after an apparently successful treatment. The same applies to patients treated with radiotherapy. Far from all patients are cured, and in many cases the disease recurs. Bilateral adrenalectomy, although always curative, causes chronic adrenal insufficiency and the remaining pituitary tumour can continue to grow and cause symptoms due to pressure on adjacent tissues, a phenomenon called Nelson's syndrome. In this paper the rate of recurrence of hypercortisolism, as well as the rate of development of Nelson's syndrome, following treatment of patients with Cushing's syndrome, will be reviewed. The aim of the paper is also to summarize clinical and biochemical factors that are associated with recurrence of hypercortisolism and how the patients should be monitored following treatment.

Prevalence, diagnosis and outcomes of treatment for primary aldosteronism

Primary aldosteronism (PA) is the most common potentially curable form of hypertension. The overproduction of aldosterone leads to an increased risk of cardiovascular and cerebrovascular events as well as adverse effects to the heart and kidney and psychological disorders. PA is mainly caused by unilateral aldosterone excess due to an aldosterone-producing adenoma or bilateral excess due to bilateral adrenocortical hyperplasia. The diagnostic work-up of PA comprises three steps: screening, confirmatory testing and differentiation of unilateral surgically-correctable forms from medically treated bilateral PA. These specific treatments can mitigate or reverse the increased risks associated with PA. Herein we summarise the prevalence, outcomes and current and future clinical approaches for the diagnosis of primary aldosteronism.

p.R209H GH1 variant challenges short stature assessment

OBJECTIVE

to describe the marked variability in clinical and biochemical patterns that are associated with a p.R209H GH1 missense variant in a large Argentinean pedigree, which makes the diagnosis of GHD elusive.

DESIGN

We describe a non-consanguineous pedigree composed by several individuals with short stature, including 2 pediatric patients with typical diagnosis of isolated growth hormone deficiency (IGHD) and 4 other siblings with severe short stature, low serum IGF-1 and IGFBP-3, but normal stimulated GH levels, suggesting growth hormone insensitivity (GHI) in the latter group.

RESULTS

Patients with classical IGHD phenotype carried a heterozygous variant in GH1: c.626G>A (p.R209H). Data from the extended pedigree suggested GH1 as the initial candidate gene, which showed the same pathogenic heterozygous GH1 variant in the four siblings with short stature and a biochemical pattern of GHI.

CONCLUSIONS

We suggest considering GH1 sequencing in children with short stature associated to low IGF-1 and IGFBP-3 serum levels, even in the context of normal response to growth hormone provocative testing (GHPT).

Clinical Utility of the Meal Tolerance Test in the Care of Patients with Type 2 Diabetes Mellitus

Objective The measurement of C-peptide immunoreactivity (CPR) is essential for evaluating the pancreatic β-cell function and selecting appropriate therapeutic agents in patients with diabetes mellitus. The meal tolerance test (MTT) is simple to administer physiological insulin-stimulating test. Previous studies have reported that several CPR-related indices are useful markers for predicting insulin requirement in type 2 diabetes. In the present study, we investigated the serum CPR response during the MTT in hospitalized patients with type 2 diabetes mellitus in order to clarify the clinical utility of the MTT. Methods We performed the MTT using a test meal with timed measurements of the serum CPR level based on the oral glucose tolerance test over 180 minutes and tested the correlation of various CPR-related indices and clinical factors in patients with type 2 diabetes mellitus. Patients The subjects were patients with type 2 diabetes mellitus who had been admitted to our hospital for diabetes management and education. The final study population consisted of 68 patients. Results The fasting CPR level was correlated with the 24-hour urinary CPR excretion and body mass index. The serum CPR level at 120 minutes in the MTT was strongly correlated with the area under the curve of CPR during the MTT. The patients who needed insulin therapy at 6 months after hospitalization showed a significant lower incremental CPR value from 0 to 120 minutes in the MTT than those who did not need insulin therapy. Conclusion The plasma C-peptide levels at 0 and 120 minutes in the MTT provide essential information for the clinical management of patients with type 2 diabetes mellitus.

Diagnostic Approaches to Neuroendocrine Neoplasms of Unknown Primary Site

Neuroendocrine neoplasms (NENs) arise from cells of neuronal and endocrine differentiation. While they are a rare entity, an increasing proportion of patients with NEN present with metastatic disease and no evident primary site using routine imaging or histopathology. NENs of unknown primary site have a poorer prognosis, often due to the challenge of selecting appropriate evidence-based management. We review the available literature and guidelines for the management of NENs of unknown primary site including clinical features, biochemical tests, histopathology, imaging, surgical exploration and localised and systemic treatments. We also discuss novel molecular techniques currently under investigation to aid primary site identification.

Atherogenic Index of Plasma (AIP) a Tool to Assess Changes in Cardiovascular Disease Risk Post Laparoscopic Sleeve Gastrectomy

Predictive indices like the atherogenic index of plasma (AIP) have been developed to estimate the risk of cardiovascular disease (CVD). Metabolic surgery is the most effective treatment for a rapid improvement of morbid obesity and its comorbidities such as type 2 diabetes (T2D) and CVD. A decreased reoccurrence of CVD after metabolic surgery has been reported by several studies. However, studies utilizing predictive indices for CVD risk in CVD-free morbid-obese patients who undertook laparoscopic sleeve gastrectomy (LSG) are lacking. Here, we use AIP as a tool to evaluate the improvement in CVD risk post-LSG in morbid-obese people who had no history of CVD. Method. We compared baseline, 6- and 12-month post-LSG score of AIP, vascular age, circulating biochemical markers related to CVD in two groups of BMI and age-matched morbid-obese participants with and without T2D. Results. At baseline, people with T2D had significantly higher AIP both, with morbid obesity (0.23 ± 0.06, p < 0.001) and normal weight (0.022 ± 0.05, p < 0.001) compared to their BMI-matched without T2D group. People with morbid obesity had low AIP (-0.083 ± 0.06). Vascular age was significantly higher in people with morbid obesity and T2D (65.8 ± 3.7year, p < 0.0001) compared to morbid obesity (37.9 ± 2.6 year). After one year, AIP was significantly reduced compared to baseline score in people with morbid obesity with/without T2D, respectively (-0.135 ± 0.07, p = 0.003; and -0.36 ± 0.04, p = 0.0002). Conclusion. Our data illuminates AIP as a reliable predictive index for CVD risk in morbid-obese people who had no history of CVD. Moreover, AIP accurately distinguishes between morbid obesity with T2D and morbid obesity and showed a rapid and significant reduction in CVD risk after LSG in people who had no history of CVD. This is a ClinicalTrials.gov registered trial (Reference NCT03038373).

Basal and metoclopramide induced prolactin secretion in lean PCOS women

Polycystic ovary syndrome (PCOS) as well as hyperprolactinemia can cause infertility. In retrospective study the prolactin levels during the oral metoclopramide test among lean PCOS woman according to four phenotypes and free androgen index (FAI) were compared. The study population consisted of 314 lean PCOS women. The population was divided into four groups according to the FAI and menstrual cycle regularity. The group A consisted 126 women with FAI≥5 and irregular menstruation, the group B- 53 patients with FAI≥5 and regular menstruation. Group C- 70 patients with FAI<5 and irregular menstruation, group D - 65 patients with FAI<5 and regular menstruation. The ratio of prolactin value in 120th minute in the metoclopramide test to the basal prolactin value was higher in group D than in groups A and B. The prolactin basal concentration was higher in patients with FAI≥5 than in patients with FAI<5, (262.9 vs 228.9 µIU/ml; p<0.001). The ratio of prolactin in 60th minute (12.3 vs 16.7; p=0.006) and in the 120th minute (10.9 versus 13.3; p<0.001) of the metoclopramide test to the basal prolactin were lower in patients with FAI≥5. The prolactin secretion in lean PCOS women may be associated with their FAI.

TERT Promoter Mutation Spatial Heterogeneity in a Metastatic Follicular Thyroid Carcinoma: Implications for Clinical Work-Up

Follicular thyroid carcinoma (FTC) is not routinely diagnosed by a preoperative fine needle aspiration biopsy (FNAB), and the final diagnosis relies on histopathological criteria visible upon microscopic examination of the excised tumor. Several markers have been proposed as helpful in the identification of follicular thyroid tumors with malignant potential and worse prognosis, of which the specific point mutations C250T and C228T in the Telomerase Reverse Transcriptase (TERT) promoter region seem to be particularly promising. We describe a patient presenting with a large pelvic mass, in which a core needle biopsy was consistent with follicular-patterned thyroid tissue positive for a Q61R NRAS mutation and the C228T TERT promoter mutation. Upon clinical investigation, a 60-mm lesion was detected in the right thyroid lobe. The ensuing FNAB was consistent with a follicular thyroid tumor, Bethesda IV, positive for the same NRAS mutation and both the C228T and C250T TERT promoter mutations. A total thyroidectomy was performed, and a widely invasive FTC was diagnosed. Tumor tissue samples from various parts of the primary lesion were investigated for TERT promoter mutations, displaying C228T in three samples and C250T in one. Interestingly, the C228T mutations showed a coupling to areas with high Ki-67 proliferation indexes. Our data indicate that TERT promoter mutations can exhibit spatial heterogeneity in FTCs, with implications for clinical management as well as providing insights into the molecular biology underlying the tumoral etiology.

The relevance of cortisol co-secretion from aldosterone-producing adenomas

AIMS AND OBJECTIVES

Adrenal adenomas are usually non-functioning, but can secrete aldosterone or cortisol. It has recently been suggested that many more adenomas than previously thought secrete more than one hormone. This has important implications for their clinical management. Our aim was to determine the frequency of cortisol co-secretion in primary hyperaldosteronism at our institution and investigate the difference in metabolic profiles and clinical outcomes between co-secreting and non-co-secreting patients.

DESIGN AND PATIENTS

A retrospective study of 25 patients with primary hyperaldosteronism who also underwent formal dexamethasone suppression tests to determine cortisol co-secretion.

MEASUREMENTS

Post-dexamethasone suppression test cortisol, serum ALT, total cholesterol, HDL-cholesterol, LDL-cholesterol, HbA1C (were recorded) and mean arterial pressure are reported in this cohort of patients with primary hyperaldosteronism.

RESULTS

Four out of 25 patients with primary hyperaldosteronism failed dexamethasone suppression tests. This suggests a frequency of co-secretion ranging between 4 and 16%. No significant difference was found in serum ALT, total cholesterol, serum HDL-cholesterol, LDL-cholesterol and mean arterial blood pressure at presentation between co-secretors and non-co-secretors.

CONCLUSION

A frequency range of 4-16% suggests that a significant proportion of patients with primary hyperaldosteronism co-secrete cortisol. Co-secretors did not have a worse metabolic profile than non-secretors. The impact of co-secretion on metabolic profile and surgical management remains unclear and warrants further study.

Diabetic kidney disease: A systematic review on the role of epigenetics as diagnostic and prognostic marker

Diabetic kidney disease is one of the most serious microvascular complications and among the leading causes of end stage renal disease. Persistently increasing albuminuria has been considered to be the central hallmark of nephropathy. However, albuminuria can indicate kidney damage for clinicians; it is not a specific biomarker for prediction of diabetic kidney disease prior to the onset of this devastating complication, and in fact all individuals with microalbuminuria do not progress to overt nephropathy. Controlled glycemia is unable to prevent nephropathy in all diabetic individuals indicating the role of other factors in progression of diabetic kidney disease. There are numerous cellular and molecular defects persisting prior to appearance of clinical symptoms. So, there is an urgent need to look for easy, novel, and accurate way to detect diabetic kidney disease prior to its beginning or at the infancy stage so that its progression can be slowed or arrested. It is now accepted that initiation and progression of diabetic kidney disease are a result of complex interactions between genetic and environmental factors. Environmental signals can alter the intracellular pathways by chromatin modifiers and regulate gene expression patterns leading to diabetes and its complications. In the present review, we have discussed a possible link between aberrant DNA methylation and altered gene expression in diabetic kidney disease. Drugs targeting to reverse epigenetic alteration can retard or stop the development of this devastating disease, just by breaking the chain of events occurring prior to the development of this microvascular complication in patients with diabetes.

The co-predictive value of a cardiovascular score for CV outcomes in diabetic patients with no atrial fibrillation

BACKGROUND

Risk factors included in the cardiovascular (CHA₂ DS₂ -VASc) score, currently used for atrial fibrillation (AF), may predispose to cardiovascular events whether or not AF is present. The aim was to explore the predictive role of CHA₂ DS₂ -VASc score on cardiovascular outcomes in diabetic patients without AF.

METHODS

We accessed individual data from 610 diabetic patients without AF at baseline included in the prospective cohort of the Malmö Diet and Cancer study. Main outcome measure was the occurrence of cardiovascular events (stroke, coronary events) and death. Mean follow-up was 14.5 ± 5 years (8845 person/years).

RESULTS

The CHA₂ DS₂ -VASc score significantly predicted the risk of all outcome measures. There was a significant increase in stroke, coronary events, and death risk by each point of CHA₂ DS₂ -VASc score elevation [stroke: adjusted hazard ratio (aHR) 1.43, 95% CI 1.14-1.79, P = 0.001; coronary events: aHR 1.55, 95% CI 1.34-1.80, P < 0.0001; death: aHR 1.94, 95% CI 1.71-2.21, P < 0.0001]. A CHA₂ DS₂ -VASc score ≥4 was associated with higher incidence of ischemic stroke (aHR 1.47, 95% CI 1.18-1.82; P = 0.001), coronary events (aHR 1.32; 95% CI 1.11-1.58; P = 0.002), and death (aHR 1.36; 95% CI 1.20-1.54; P < 0.001).

CONCLUSIONS

In this population-based study on diabetic patients without AF, the CHA₂ DS₂ -VASc score was an independent predictor of ischemic stroke, coronary events, and overall mortality. Regardless of the AF status, the CHA₂ DS₂ -VASc score might represent a rapid and user-friendly tool for clinical assessment of diabetic patients at higher cardiovascular risk.

[Functional diagnostics in endocrinology]

When investigating many endocrinological diseases, basal laboratory parameters are not sufficient to distinguish between physiological and pathological hormone secretion. Functional diagnostics plays a decisive role in this context. Stimulation and suppression tests are used depending on whether under- or over-function needs to be diagnosed. This review article discusses selected functional tests, each of which plays an important role in current guidelines. Indications and test principles, including their performance, reliability, and limitations, are discussed. Topics covered include the ACTH stimulation test for the diagnosis of adrenal cortex insufficiency and the dexamethasone inhibition test for suspected Cushing's syndrome, as well as functional tests for the diagnosis of primary hyperaldosteronism, pheochromocytoma, acromegaly, growth hormone deficiency, thyroid nodules and suspicion of medullary thyroid carcinoma, insulinoma, and Zollinger-Ellison syndrome. Functional tests that are explicitly not recommended are also addressed.

Mixed-meal tolerance test to assess residual beta-cell secretion: Beyond the area-under-curve of plasma C-peptide concentration

AIMS

Residual beta-cell secretion in type 1 diabetes is commonly assessed by area-under-curve of plasma C-peptide concentration (AUCCpep ) following mixed-meal tolerance test (MMTT). We aimed to investigate alternative measures of beta-cell responsiveness.

METHODS

We analyzed data from 32 youth (age 7 to 17 years) undergoing MMTT within 6 months of type 1 diabetes diagnosis. We related AUCCpep with (a) validated mechanistic index of postprandial beta-cell responsiveness MI accounting for glucose level during MMTT, and (b) pragmatic marker calculated as baseline plasma C-peptide concentration corrected for baseline plasma glucose concentration.

RESULTS

Postprandial responsiveness MI was correlated with age and BMI SDS (Rs = 0.66 and 0.44, P < 0.01 and P < 0.05) and was more correlated with glycated hemoglobin than AUCCpep (Rs = 0.79, P = 0.04). The pragmatic marker was highly correlated with AUCCpep (Rs = 0.94, P < 0.01).

CONCLUSIONS

Postprandial responsiveness MI may be more relevant to glucose control than AUCCpep . Baseline C-peptide corrected for baseline glucose appears to be a suitable surrogate of AUCCpep if MMTT is not performed.

Autonomic testing: which value for each cardiovascular test? An observational study

AIMS

Cardiovascular autonomic testing is time consuming when adopting the entire Ewing battery of tests, hence, clinicians usually adopt an empirically reduced number of tests which may give controversial results. Our purpose was to examine the reliability of the cardiovascular tests most commonly used in autonomic diagnoses.

METHODS

We tested 334 subjects, from an original group of 3745, who had shown an altered deep breathing test to both Lying to standing and Valsalva manoeuvre, assuming a value of postural hypotension of more than 15 mmHg as a sign of almost true dysautonomia.

RESULTS

VM showed the highest sensitivity (85%) and, when coupled to LS, highest specificity (83%).

CONCLUSIONS

VM could be useful when screening for possible or early autonomic neuropathy, VM + LS is useful as a diagnostic tool for probable or advanced autonomic neuropathy, and VM + LS + PH is useful for certain diagnosis of definite or late stage autonomic neuropathy.

Management of familial hyperparathyroidism syndromes: MEN1, MEN2, MEN4, HPT-Jaw tumour, Familial isolated hyperparathyroidism, FHH, and neonatal severe hyperparathyroidism

While primary hyperparathyroidism (PHPT) generally represents a common endocrine disorder, being the more frequent cause of hypercalcemia in outpatients, familial forms of PHPT (FPHPT) account for no more than 2-5% of the overall PHPT. In the last decades, many technical progresses in both molecular and biochemical-radiological evaluation have been made, and substantial advancements in understanding these disorders have been reached. Differences both in the pathogenesis and clinical presentation exist among the various hyperparathyroid syndromic forms, and, since FPHPT is frequently associated to other endocrine, proliferative and/or functional disorders, as also non-endocrine tumours, with varying clinical spectrum of occurrence in each syndrome, its early clinically detection for appropriately preventing complications (i.e. kidney and bone disorders) is strictly advised. In this review, the clinical-biochemical features and diagnostic procedures of each FPHPT form will be summarized and a general overview on surgical and pharmacological approaches to FPHPT has been also considered.

Anti-müllerian hormone in the pathophysiology and diagnosis of polycystic ovarian syndrome

PURPOSE OF REVIEW

Polycystic ovarian syndrome (PCOS) is the most common cause of chronic anovulation and hyperandrogenism in young women and represents a true public health concern and an economic burden.

RECENT FINDINGS

The pathophysiology of PCOS is still not fully understood, but progresses have been made and the relationships between anti mullerian hormone (AMH), follicle stimulating hormone, luteinizing hormone, E2 and androgens have been explored. The follicle excess plays a central role in the syndrome and AMH is definitively a major component of this phenomena.

SUMMARY

The aim of this chapter is to present the recent work studying the role of AMH in the pathophysiology of PCOS and to discuss the improvement that serum AMH assay brings in the diagnosis of PCOS.

Evaluation of testicular function in prepubertal children

INTRODUCTION

The assessment of testicular function is not currently performed in childhood. The aim of this review was to address the usefulness of serum Anti-Müllerian Hormone (AMH), inhibin B, and testicular volume (TV) evaluation in children.

REVIEW

Serum AMH and inhibin B levels reflect Sertoli cells (SCs) health and number, SCs maturation degree and their exposure to FSH and to intra-tubular testosterone (T). These hormones might be helpful in discriminating between congenital central hypogonadism (cHH) and constitutional delay in growth and puberty (CDGP) and in case of clinical suspicious of precocious puberty. Furthermore, low AMH and/or inhibin B levels have been observed in children with primary testicular disorders, suggesting the existence of SC dysfunction. TV also provides useful information on testicular health. Recently, a medical calculator, requiring testis length and the stage of genital development, has been developed to easily derive TV.

CONCLUSIONS

The evidence supports the usefulness of AMH, inhibin B and TV evaluation for the early diagnosis of puberty disorders and primary testicular damage. We suggest the measurement of TV by using the medical calculator in all children and to reserve AMH and inhibin B measurements to those cases of no testicular growth, clinical suspicious of puberty disorders or in children at risk for spermatogenesis damage. This work-up might allow the early detection of testicular tubular damage which, in turn, may be useful to prevent the oncoming male infertility in adulthood.

Comparison of Seated With Recumbent Saline Suppression Testing for the Diagnosis of Primary Aldosteronism

CONTEXT

Failure of plasma aldosterone suppression during fludrocortisone suppression testing (FST) or saline suppression testing (SST) confirms primary aldosteronism (PA). Aldosterone is often higher upright than recumbent in PA; upright levels are used during FST. In a pilot study (24 patients with PA), seated saline suppression testing (SSST) was more sensitive than recumbent saline suppression testing (RSST).

OBJECTIVE, DESIGN, AND PATIENTS

The current validation study involved 100 patients who underwent FST, RSST, and SSST, eight before and after unilateral adrenalectomy. Of the 108 FSTs, 73 confirmed and 18 excluded PA. Four patients with inconclusive FST lateralized on adrenal venous sampling, making a total of 77 with PA.

RESULTS

The area under the receiver operating characteristic (ROC) curve was greater for SSST than RSST (0.96 vs. 0.80; P < 0.01). ROC analysis predicted optimal cutoff aldosterone levels of 162 pmol/L for SSST and 106 pmol/L for RSST. At these cutoffs, SSST showed high sensitivity for PA (87%) that markedly exceeded that for RSST (38%; P < 0.001) but similar specificity (94 vs. 94%; not significant). SSST was more sensitive than RSST in detecting both unilateral (n = 28, 93% vs. 68%, P < 0.05) and bilateral (n = 40, 85% vs. 20%, P < 0.001) forms of PA. Only three SSST (vs. 9 RSST and 17 FST) results were inconclusive.

CONCLUSIONS

SSST is highly sensitive and superior to RSST in identifying both unilateral and bilateral forms of PA and has a low rate of false positives and inconclusive results. It therefore offers a reliable and much less complicated and expensive alternative to FST for confirming PA.

DEXAMETHASONE STRESS TEST: A PILOT CLINICAL STUDY FOR IDENTIFICATION OF INDIVIDUALS HIGHLY PRONE TO DEVELOP TYPE 2 DIABETES

OBJECTIVE

We examined whether the "Dexamethasone Stress Test" exhibits the requisite high predictive ability to identify individuals highly prone to develop type 2 diabetes mellitus (T2DM).

METHODS

Seven years ago, we administered an oral glucose tolerance test (OGTT) to 33 individuals without T2DM and repeated the OGTT 24 hours after a single oral dose of 8 mg dexamethasone (Dex); all participants had a first-degree relative with T2DM, and close to half had prediabetes. We calculated receiver operating characteristic (ROC) curves for all parameters derived from the OGTT before and after Dex in individuals who subsequently developed diabetes compared to individuals who did not.

RESULTS

At 7 years of follow-up, 9 individuals had developed T2DM, while 24 remained without diabetes. None of the OGTT-derived parameters before administration of Dex had an area under the ROC curve of >0.8. However, 24 hours after Dex, three parameters, including fasting plasma insulin, homeostatic model assessment-insulin resistance, and 2-hour plasma glucose level, exhibited areas under the ROC curves of 0.84, 0.86, and 0.92, respectively.

CONCLUSION

The Dexamethasone Stress Test appears to be a good to excellent test in identifying individuals highly prone to develop T2DM.

ABBREVIATIONS

AUC = area under the curve; Dex = dexamethasone; HOMA-IR = homeostatic model assessment-insulin resistance; NGT = normal glucose tolerance; OGTT = oral glucose tolerance test; PreDiab = prediabetes; ROC = receiver operating characteristic; T2DM = type 2 diabetes mellitus.

FRAX tool in type 2 diabetic subjects: the use of HbA1c in estimating fracture risk

AIMS

Patients with type 2 diabetes mellitus (T2DM) have an increased risk of fractures, despite having greater bone mineral density (BMD) than non-diabetic subjects. This has led to the hypothesis that the presence of impaired bone quality among diabetics reduces bone strength. The Fracture Risk Assessment Score (FRAX) algorithm, introduced to facilitate the evaluation of fracture risk, underestimates the risk of fracture in diabetic patients. The purpose of this study is to confirm the relationship between the degree of metabolic compensation and the 10-year probability of a major fracture or a hip osteoporotic fracture observed in our previous study and to ascertain whether glycosylated hemoglobin (HbA_1c) can improve the predictive value of FRAX in patients with T2DM.

METHODS

Our data derive from a retrospective clinical study conducted at the "Tor Vergata" Polyclinic in Rome on 6355 subjects over 50 years of age evaluated for osteoporosis. All available clinical records were examined. HbA_1c was available for 242 of these subjects and all had had a Dual-energy X-ray Absorption (DXA) scan of the lumbar spine and femoral neck. The risk of fracture was estimated using the Italian version of the FRAX algorithm.

RESULT

Patients with T2DM had BMD and T-scores higher than those of non-diabetic subjects, while FRAX average values were higher in the non-diabetic group. HbA_1c and FRAX are inversely correlated with each other: for each incremental percentage point of HbA_1c growth, the FRAX major osteoporotic fracture probability is reduced by 0.915 points and the FRAX hip osteoporotic fracture probability by 1.438 points. The introduction of a correction factor derived from HbA_1c, resulted in mean FRAX values of diabetic patients equivalent to those of non-diabetic subjects.

CONCLUSIONS

We propose a correction factor derived from HbA_1c that could enhance the predictive ability of fracture risk estimated by the FRAX algorithm in subjects with T2DM.

Testosterone replacement therapy: For whom, when and how?

The finding of low circulating testosterone level in men is relatively frequent. The symptoms of hypogonadism are very frequent in the aging men. However, the diagnosis of hypogonadism is often neglected and the opportunity to replace low testosterone in older men is highly debated. The aim of this narrative review is to summarize the steps necessary to formulate a proper diagnosis and to guide toward an individualized treatment. While universally recognized the need to treat the young adults with known causes of pituitary or testicular failure, there are controversies on the cost-benefit of treating testosterone deficiency in older men. Discrepancies among the several available guidelines do not help to clarify the scenario, however, the recent larger clinical trials have shed some light on the fact that testosterone treatment carries some benefit, that is not free from risks. We provide an updated review of the diagnostic hallmarks, the several treatment modalities, with their advantages and disadvantages, and how to individualize and monitor treatment in order to maximize the benefits and minimize the risks. The treatment of male hypogonadism can no longer be downgraded and must become part of the cultural baggage of the endocrinologist.