Diagnostic Accuracy of the Desmopressin Stimulation Test in the Comprehensive Assessment of ACTH-Dependent Cushing's Syndrome: A Comparative Analysis with BIPSS and TSS.

BACKGROUND: Cushing's syndrome (CS) poses diagnostic challenges, particularly in distinguishing pituitary-dependent Cushing's syndrome, Cushing's disease (CD), from the ectopic ACTH syndrome (EAS). This study evaluated the diagnostic value of the desmopressin stimulation test (DST) in patients with ACTH-dependent CS in helping this discrimination. METHODS: Twenty-three ACTH-dependent CS patients underwent sequential DST, bilateral inferior petrosal sinus sampling (BIPSS), and transsphenoidal surgery (TSS). Two definitions of a positive DST results were applied. Diagnostic performance was assessed using sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and likelihood ratios. To avoid bias from predetermined criteria, we generated univariate receiver-operating characteristic (ROC) curves, plotting sensitivity against 1-specificity at various percentage cortisol and ACTH response levels. RESULTS: Against BIPSS, DST demonstrated robust sensitivity (Definition 1: 90.0%, Definition 2: 76.2%) and overall accuracy (Definition 1: 87.0%, Definition 2: 73.9%). PPV was high (Definition 1: 95.0%, Definition 2: 94.1%), but NPV indicated potential false negatives. Compared to TSS, DST showed good sensitivity (Definition 1: 90.9-77.3%) and PPV (100.0%) but limited NPV (16.7%). The likelihood ratios emphasized the diagnostic value of the test. Notably, against TSS, DST showed perfect discriminatory power (AUC 1.000 for percent ACTH, 0.983 for percent cortisol). CONCLUSION: The desmopressin test shows promise in accurately identifying the underlying cause of ACTH-dependent CS, potentially reducing the reliance on invasive procedures and providing a practical solution for managing complex cases. Further research with larger cohorts is required to validate the utility of the DST in routine clinical practice.

Indication to dynamic and invasive testing in Cushing's disease according to different neuroradiological findings.

PURPOSE: Dynamic testing represents the mainstay in the differential diagnosis of ACTH-dependent Cushing's syndrome. However, in case of undetectable or detectable lesion < 6 mm on MRI, bilateral inferior petrosal sinus sampling (BIPSS) is suggested by current guidelines. Aim of this study was to analyze the performance of CRH, desmopressin and high-dose dexamethasone suppression test (HDDST) in the differential diagnosis of ACTH-dependent Cushing's syndrome as well as the impact of invasive and noninvasive tests on surgical outcome in patients affected by Cushing's disease (CD). METHODS: Retrospective analysis on 148 patients with CD and 26 patients with ectopic ACTH syndrome. RESULTS: Among CD patients, negative MRI/lesion < 6 mm was detected in 97 patients (Group A); 29 had a 6-10 mm lesion (Group B) and 22 a macroadenoma (Group C). A positive response to CRH test, HDSST and desmopressin test was recorded in 89.4%, 91·4% and 70.1% of cases, respectively. Concordant positive response to both CRH/HDDST and CRH/desmopressin tests showed a positive predictive value of 100% for the diagnosis of CD. Among Group A patients with concordant CRH test and HDDST, no difference in surgical outcome was found between patients who performed BIPSS and those who did not (66.6% vs 70.4%, p = 0.78). CONCLUSIONS: CRH, desmopressin test and HDDST have high accuracy in the differential diagnosis of ACTH-dependent CS. In patients with microadenoma < 6 mm or non-visible lesion, a concordant positive response to noninvasive tests seems sufficient to diagnose CD, irrespective of MRI finding. In these patients, BIPSS should be reserved to discordant tests.

Utility of bilateral inferior petrosal sinus sampling for diagnosis and lateralization of Cushing's disease in the pediatric population: case series and review of the literature.

OBJECTS: Cushing's disease (CD) is the most common cause of ACTH-dependent hypercortisolism in children age ≥ 7. The utility of bilateral inferior petrosal sinus sampling (BIPSS), an important test in adults, is less defined in children. We present a case series of children with ACTH-dependent hypercortisolemia and review the literature to assess the utility of BIPSS in the diagnosis and localization of CD. METHODS: We performed an IRB-approved chart review of patients aged ≤ 18 with ACTH-dependent hypercortisolism at MGH between 2000 and 2019 and collected clinical, laboratory, radiographic, BIPSS, surgical, and outcomes data. RESULTS: In our cohort (n = 21), BIPSS had a sensitivity of 93% and specificity of 100% for diagnosis of CD. Compared to surgery, successful BIPSS correctly predicted adenoma laterality in 69% of cases vs. 70% by MRI. Among patients with lesions ≥ 4 mm (n = 9), BIPSS correctly lateralized in 50% vs. 100% by MRI. In patients with subtle lesions (< 4 mm, n = 7), BIPSS correctly lateralized in 80% vs. 71% by MRI. In patients (n = 4) with CD and negative MRIs, BIPSS correctly lateralized in 75% cases. Surgical cure was achieved in 90% of patients and 95% of patients had long-term disease control. CONCLUSIONS: In our cohort (n = 21; n = 20 CD, n = 1 ectopic ACTH secretion), BIPSS was sensitive and specific for the diagnosis of CD. Compared to MRI, BIPSS was not additionally helpful for lateralization in patients with lesions ≥ 4 mm on MRI. BIPSS was helpful in guiding surgical exploration and achieving immediate postoperative remission among patients with subtle and negative MRI findings.

Diagnostic Pitfalls in Cushing Disease: Surgical Remission Rates, Test Thresholds, and Lessons Learned in 105 Patients.

CONTEXT: Confirming a diagnosis of Cushing disease (CD) remains challenging, yet is critically important before recommending transsphenoidal surgery for adenoma resection. OBJECTIVE: To describe predictive performance of preoperative biochemical and imaging data relative to post-operative remission and clinical characteristics in patients with presumed CD. DESIGN, SETTING, PATIENTS, INTERVENTIONS: Patients (n = 105; 86% female) who underwent surgery from 2007 through 2020 were classified into 3 groups: group A (n = 84) pathology-proven ACTH adenoma; group B (n = 6) pathology-unproven but with postoperative hypocortisolemia consistent with CD; and group C (n = 15) pathology-unproven, without postoperative hypocortisolemia. Group A + B were combined as confirmed CD and group C as unconfirmed CD. MAIN OUTCOMES: Group A + B was compared with group C regarding predictive performance of preoperative 24-hour urinary free cortisol (UFC), late night salivary cortisol (LNSC), 1-mg dexamethasone suppression test (DST), plasma ACTH, and pituitary magnetic resonance imaging (MRI). RESULTS: All groups had a similar clinical phenotype. Compared with group C, group A + B had higher mean UFC (P < 0.001), LNSC (P = 0.003), DST (P = 0.06), and ACTH (P = 0.03) and larger MRI-defined lesions (P < 0.001). The highest accuracy thresholds were: UFC 72 µg/24 hours; LNSC 0.122 µg/dL, DST 2.70 µg/dL, and ACTH 39.1 pg/mL. Early (3-month) biochemical remission was achieved in 76/105 (72%) patients: 76/90(84%) and 0/15(0%) of group A + B vs group C, respectively, P < 0.0001. In group A + B, nonremission was strongly associated with adenoma cavernous sinus invasion. CONCLUSIONS: Use of strict biochemical thresholds may help avoid offering transsphenoidal surgery to presumed CD patients with equivocal data and improve surgical remission rates. Patients with Cushingoid phenotype but equivocal biochemical data warrant additional rigorous testing.

Assessment of Vitamin D Metabolism in Patients with Cushing's Disease in Response to 150,000 IU Cholecalciferol Treatment.

In this study we aimed to assess vitamin D metabolism in patients with Cushing's disease (CD) compared to healthy individuals in the setting of bolus cholecalciferol treatment. The study group included 30 adults with active CD and the control group included 30 apparently healthy adults with similar age, sex and BMI. All participants received a single dose (150,000 IU) of cholecalciferol aqueous solution orally. Laboratory assessments including serum vitamin D metabolites (25(OH)D3, 25(OH)D2, 1,25(OH)2D3, 3-epi-25(OH)D3 and 24,25(OH)2D3), free 25(OH)D, vitamin D-binding protein (DBP) and parathyroid hormone (PTH) as well as serum and urine biochemical parameters were performed before the intake and on Days 1, 3 and 7 after the administration. All data were analyzed with non-parametric statistics. Patients with CD had similar to healthy controls 25(OH)D3 levels (p > 0.05) and higher 25(OH)D3/24,25(OH)2D3 ratios (p < 0.05) throughout the study. They also had lower baseline free 25(OH)D levels (p < 0.05) despite similar DBP levels (p > 0.05) and lower albumin levels (p < 0.05); 24-h urinary free cortisol showed significant correlation with baseline 25(OH)D3/24,25(OH)2D3 ratio (r = 0.36, p < 0.05). The increase in 25(OH)D3 after cholecalciferol intake was similar in obese and non-obese states and lacked correlation with BMI (p > 0.05) among patients with CD, as opposed to the control group. Overall, patients with CD have a consistently higher 25(OH)D3/24,25(OH)2D3 ratio, which is indicative of a decrease in 24-hydroxylase activity. This altered activity of the principal vitamin D catabolism might influence the effectiveness of cholecalciferol treatment. The observed difference in baseline free 25(OH)D levels is not entirely clear and requires further study.

An Optimized Pathway for the Differential Diagnosis of ACTH-Dependent Cushing's Syndrome Based on Low-Dose Dexamethasone Suppression Test.

Context: Traditionally, low-dose dexamethasone suppression test (LDDST) was used to confirm the diagnosis of Cushing's syndrome (CS), and high-dose dexamethasone suppression test (HDDST) was used to differentiate Cushing's disease (CD) and ectopic adrenocorticotropin (ACTH) syndrome (EAS), but some studies suggested that HDDST might be replaced by LDDST. For the differential diagnosis of CS, dexamethasone suppression test was usually combined with other tests such as bilateral petrosal sinus sampling (BIPSS) and pituitary magnetic resonance imaging, but the optimal pathway to incorporate these tests is still controversial. Objectives: To develop an optimized pathway for the differential diagnosis of CD and EAS based on LDDST. Design and Setting: Single-center retrospective study (2011-2019). Patients: Two hundred sixty-nine CD and 29 EAS patients with pathological diagnosis who underwent consecutive low- and high-dose DST. Results: For the differential diagnosis of CD and EAS, the area under curve (AUC) of LDDST using urine free cortisol (0.881) was higher than that using serum cortisol (0.685) (p < 0.001) in head-to-head comparison among a subgroup of 108 CD and 10 EAS. The AUC of LDDST (0.883) was higher than that of HDDST (0.834) among all the included patients. With the cutoff of <26%, the sensitivity and specificity of LDDST were 39.4% and 100%. We designed a new pathway in which BIPSS was only reserved for those patients with unsuppressed LDDST and adenoma <6mm, yielding an overall sensitivity of 97.7% and specificity of 86.7%. Conclusion: LDDST had similar value to HDDST in differentiating CD and EAS using the specific cutoff point. The pathway that combined LDDST and BIPSS could differentiate CD and EAS accurately.

Metabolic profiling of serum from dogs with pituitary-dependent hyperadrenocorticism.

Hyperadrenocorticism (HAC) is one of the most common endocrine diseases in dogs characterized by excessive cortisol production caused by an adrenocorticotropic hormone (ACTH)-secreting tumor, namely pituitary-dependent HAC (PDH) or cortisol-secreting adrenal tumor. Metabolomics presents the ability to identify small molecule metabolites. Thus, the use of metabolomics techniques in canine PDH can provide information about the pathophysiology and metabolic changes in this disease. This study aimed to identify and compare differences in serum metabolites between dogs with PDH and healthy dogs. The metabolomic profile of 20 dogs diagnosed with PDH was compared with 20 healthy dogs using liquid chromatography/mass spectrometry (LC/MS), and metabolite discrimination was performed using partial least squares-discriminant analysis (PLS-DA), the variable important in projection (VIP) and fold changes (FC) group-wise comparisons. The hypergeometric test identified the significantly altered pathways. A total of 21 metabolites were found to be significantly different between the two groups. The major alterations were found in arachidonic and decanoic acid, and phospholipids related to phosphatidylcholine (PC), phosphatidylethanolamine (PE) and phosphatidylinositol (PI). These metabolites are related to insulin resistance and other complications (i.e. hypertension). Our results indicate that PDH produces changes in serum metabolites of dogs, and the knowledge of these changes can aid to better understanding of pathophysiological processes involved and contribute to potentially detect new biomarkers for this disease.

Revalidation of inferior petrosal sinus sampling: the latest results from a single-center experience.

Cushing's disease (CD), which manifests as excess cortisol secretion, is caused by adrenocorticotrophic hormone (ACTH)-secreting pituitary adenomas. Such adenomas are occasionally difficult to identify on magnetic resonance imaging (MRI), and thorough endocrinological examination may be required to detect them. Inferior petrosal sinus (IPS) sampling (IPSS) has been the gold standard test for distinguishing CD from ectopic ACTH syndrome (EAS). However, IPSS is an invasive procedure, and proper catheterization is occasionally challenging due to anatomical variations. Thus, there have been ongoing debates regarding the necessity of this procedure. Here, we present our recent IPSS data derived from the analysis of 65 patients who were referred to us for possible CD between April 2018 and December 2020 after undergoing meticulous endocrinological testing. Even with detailed MRI, no obvious lesions were identified in 19 patients. IPSS performed on these 19 individuals identified an IPS-to-peripheral ACTH gradient in 15 of them. The four patients who lacked this gradient were subjected to a classical algorithm using concurrently measured prolactin levels, the results of which were consistent with their ultimately confirmed diagnoses: two true-positive and two true-negative diagnoses. These findings support the validity of the algorithm and demonstrate that the prolactin-adjusted IPS-to-peripheral ACTH ratio can improve the differentiation between CD and EAS. We had no false-negative results, but three patients were false-positive. Consequently, those three patients in which no apparent tumor was clarified during surgery could not have any endocrinological improvement postoperatively.

Circulating microRNA Expression in Cushing's Syndrome.

Context: Cushing's syndrome (CS) is a rare disease of endogenous hypercortisolism associated with high morbidity and mortality. Diagnosis and classification of CS is still challenging. Objective: Circulating microRNAs (miRNAs) are minimally invasive diagnostic markers. Our aim was to characterize the circulating miRNA profiles of CS patients and to identify distinct profiles between the two major CS subtypes. Methods: We included three groups of patients from the German Cushing's registry: ACTH-independent CS (Cortisol-Producing-Adenoma; CPA), ACTH-dependent pituitary CS (Cushing's Disease; CD), and patients in whom CS had been ruled out (controls). Profiling of miRNAs was performed by next-generation-sequencing (NGS) in serum samples of 15 CS patients (each before and after curative surgery) and 10 controls. Significant miRNAs were first validated by qPCR in the discovery cohort and then in an independent validation cohort of 20 CS patients and 11 controls. Results: NGS identified 411 circulating miRNAs. Differential expression of 14 miRNAs were found in the pre- and postoperative groups. qPCR in the discovery cohort validated 5 of the significant miRNAs from the preoperative group analyses. Only, miR-182-5p was found to be significantly upregulated in the CD group of the validation cohort. Comparing all CS samples as a group with the controls did not reveal any significant differences in expression. Outcome: In conclusion, our study identified miR-182-5p as a possible biomarker for CD, which has to be validated in a prospective cohort. Furthermore, our results suggest that presence or absence of ACTH might be at least as relevant for miRNA expression as hypercortisolism itself.

The association between insulin-like growth factor 1 levels within reference range and early postoperative remission rate in patients with Cushing's disease.

INTRODUCTION: The relationship between growth hormone (GH)/insulin-like growth factor 1 (IGF-1) and glucocorticoids (GC) was examined in various studies. Long-term GC treatment was shown to decrease GH concentration and, interestingly, to increase IGF-1 concentration. We performed a retrospective study in order to examine how preoperative IGF-1 concentrations vary within the reference range and if tertiles of age- and sex-adjusted normal IGF-1 are predictive for early postoperative remission in the patients with Cushing's Disease (CD). PATIENTS AND METHODS: Patients diagnosed with CD were retrospectively evaluated. After the exclusion of 67 patients, a final cohort of 250 CD patients were included. Age- and sex-adjusted normal IGF-1 levels were divided into tertiles (T1, T2 and T3). Early postoperative remission was defined as a nadir morning cortisol concentration measured within the first 3 consecutive days following surgery of less than 5 µg/dL (138 nmol/L). RESULTS: Early postoperative remission rate was the lowest in T1 and highest in T3; 49.1% (n = 28) versus 77.3% (n = 75), p = .001, respectively. Binary logistic regression analysis showed the remission rate in T3 was three times higher than that in T1 (p = .003). Cortisol and ACTH concentration were significantly higher and GH concentrations were significantly lower in T1 compared to those in the other two tertiles. CONCLUSIONS: As the first study evaluating the correlation between early postoperative remission rate in patients with CD and the tertiles of normal age- and sex-adjusted IGF-1 levels, we have shown that higher IGF-1 levels could predict better outcome in CD.

Postoperative Day 1 Morning Cortisol Value as a Biomarker to Predict Long-term Remission of Cushing Disease.

CONTEXT: Recurrence of Cushing disease (CD) can occur even decades after surgery. Biomarkers to predict recurrence of CD after surgery have been studied but are inconclusive. OBJECTIVE: The aim of our study was to identify specific biomarkers that can predict long-term remission after neurosurgery. DESIGN: Identification of specific biomarkers to predict long-term remission of CD was performed by logistic regression analysis followed by Kaplan-Meier survival analysis, using recurrence as the dependent variable. SETTING: A total of 260 patients with CD identified from our institutional research patient data registry search tool and from patients who presented to our longitudinal multidisciplinary clinic between May 2008 and May 2018 underwent statistical analysis. INTERVENTIONS: Data on clinical features, neuro-imaging study, pathology, biochemistry, and treatments were collected by reviewing digital chart records. MAIN OUTCOME MEASURE: Postoperative cortisol as a biomarker to predict long-term remission after surgical treatment for CD. RESULTS: By logistic regression analysis, postoperative day 1 (POD1) morning (5-10 am) serum cortisol, female sex, and proliferative index had significant association with CD recurrence (odds ratio [OR] = 1.025, 95% CI: 1.002-1.048, P = .032). In contrast, the postoperative nadir cortisol (OR = 1.081, 95% CI: 0.989-1.181, P = .086), urinary free cortisol (OR = 1.032, 95% CI: 0.994-1.07, P = .098), and late night salivary cortisol (OR = 1.383, 95% CI: 0.841-2.274, P = .201) had no significant correlation with recurrence. A significant association between POD1 morning serum cortisol and long-term CD remission was verified by Kaplan-Meier analysis when using POD1 morning serum cortisol <5 µg/dL as the cut-off. CONCLUSIONS: The POD1 morning serum cortisol level has a significant association with CD recurrence.

Diabetes, Active Disease, and Afternoon Serum Cortisol Levels Predict Cushing's Disease Mortality: A Cohort Study.

CONTEXT: Cushing's disease (CD) is a life-threating disease, with increased mortality in comparison with the general population. OBJECTIVE: This study aimed to evaluate standardized mortality ratios (SMRs) in CD patients. We also analyzed independent risk factors related to increased mortality. DESIGN: We conducted a longitudinal cohort study in a 3rd level specialty center, from 1979 to 2018, in patients with CD. RESULTS: From 1375 cases with a pathology diagnosis of pituitary adenoma, 191 cases had the confirmed diagnosis of CD (14%). A total of 172 patients completed follow-up, with a mean age at diagnosis of 33 ±â€…11 years, female predominance (n = 154, 89.5%), majority of them with microadenoma (n = 136, 79%), and a median follow-up of 7.5 years (2.4-15). Eighteen patients (10.5%) died, 8 of them (44%) were with active CD, 8 (44%) were under remission, and 2 (11%) were under disease control. Estimated all-cause SMR = 3.1, 95% confidence interval (CI) 1.9-4.8, P < 0.001. Cardiovascular disease was the main cause of death (SMR = 4.2, 1.5-9.3, P = 0.01). Multivariate Cox regression models adjusted for potential cofounders showed that diabetes (HR = 5.2, IC 95% 1.8-15.4, P = 0.002), high cortisol levels after 1600 hours at diagnosis (3.4, 2.3-7.0, P = 0.02), and active CD (7.5, 3.8-17.3, P = 0.003) significantly increased the risk of mortality. CONCLUSIONS: Main cause of CD mortality was cardiovascular disease. Main risk factors for mortality were uncontrolled diabetes, persistently high cortisol levels after 1600 hours at diagnosis, and active disease at last follow-up.

Successful management of a patient with active Cushing's disease complicated with coronavirus disease 2019 (COVID-19) pneumonia.

We provide the details of the successful management of a patient with active Cushing's disease complicated with coronavirus disease 2019 (COVID-19) pneumonia. The patient was a 27-year-old Japanese female healthcare worker who was scheduled to undergo pituitary surgery for Cushing's disease. She had been in close contact with an undiagnosed patient infected with COVID-19 and then developed COVID-19 pneumonia. Despite a lack of known risk factors associated with severe COVID-19 infection, the patient's dyspnea worsened and her respiratory condition deteriorated, as indicated by the need for 7 L/min oxygen supply by mask to maintain her oxygen saturation at >90%. Medical treatment was initiated to control hypercortisolism by the 'block and replace' regimen using steroidogenesis inhibitors and hydrocortisone. The COVID-19 pneumonia improved with multi-modal treatment including antiviral therapy. One month later, after a negative severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) test result and with appropriate protection against virus transmission to medical staff in the operating room and daily medical care nurses, trans-sphenoidal surgery was performed by our highly experienced pituitary surgeon. One month after the surgery, the patient's basal ACTH and cortisol levels and urinary free cortisol were all under the detection limit. Surgical remission was expected. Since hypercortisolism due to active Cushing's disease may worsen a COVID-19 infection, multi-disciplinary management that includes appropriate and prompt treatment strategies is mandatory in such cases.

Predictive factors for the recurrence of Cushing's disease after surgical treatment in childhood.

INTRODUCTION: Cushing's disease (CD) is a rare cause of hypercortisolaemia caused by excessive adrenocorticotropic hormone (ACTH) excretion by a pituitary adenoma. Data on the predictive factors for the recurrence of the disease are limited in comparison with those for the adult population. The identification of the predictive factors for CD recurrence in patients after surgical treatment in childhood was the aim of the presented study. MATERIAL AND METHODS: A retrospective analysis of 26 CD patients, mean age at the time of diagnosis 13.46 years, treated at the Children's Memorial Health Institute (CMHI) in the years 1994-2018. Two time points were set at which the follow-up (FU) of patients was finished. The first time point (shorter FU, 24 patients) was set when the patients completed their treatment at the CMHI. The second time point (longer FU, 26 patients) was determined on the basis on the time when adult patients (previous CMHI patients) completed the author's questionnaire. In the case of the other patients (current CMHI paediatric patients and patients who did not respond to the questionnaire), the latest FU in this second time point was made during the last visit to the CMHI. The predictors of disease recurrence were evaluated by the construction of a logistic regression model and receiver operating characteristics. RESULTS: The average FU after transsphenoidal pituitary surgery (TSS) of 26 patients was 10.23 years (0.67-24.50). Recurrence of CD occurred in four out of 26 patients (15.4%) after an average time of 3.6 years (0.92-8.08) following definitive treatment. The results of the statistical analysis of potential predictive factors for CD recurrence were not conclusive, with no variables confirmed above the statistical significance threshold of p < 0.05. As regards the longer FU, two potential predictors: mean cortisol level at night (p = 0.10) and max. ACTH level after ovine corticotropin-releasing hormone (oCRH) test (p = 0.10), were the closest to meeting the assumed threshold of statistical significance. CONCLUSION: Recurrence of CD may be diagnosed even a long time after its effective treatment. It is possible that cortisol levels at night and ACTH values in oCRH test before TSS may be helpful to predict which patients may experience a recurrence after successful initial treatment. However, further studies on a larger sample are needed to confirm this hypothesis.

Human Corticotropin-Releasing Hormone Tests: 10 Years of Real-Life Experience in Pituitary and Adrenal Disease.

CONTEXT: The human corticotropin-releasing hormone (CRH) test (hCRHtest) is used to differentiate Cushing disease (CD) from ectopic adrenocorticotropin (ACTH) secretion (EAS), to assess autonomous cortisol secretion by the adrenal glands, and to characterize pseudo-Cushing syndrome (CS) or adrenal insufficiency (AI). MAIN OUTCOME MEASURE: The main outcome measure of this study was to assess the diagnostic accuracy of the hCRHtest. METHODS: We measured ACTH and cortisol levels; collected the peak values (peakACTH and peakcortisol), and calculated the percentage increases (∆%ACTH and ∆%cortisol) after an intravenous bolus of 100 µg hCRH. DESIGN AND SETTING: This cross-sectional study of hCRH tests from 2010 to 2019 took place in a referral university hospital center. PATIENTS: We enrolled 200 patients: 86 CD, 15 EAS, 18 adrenal CS, 25 mild adrenal autonomous cortisol secretion, 31 pseudo-CS, and 25 suspected AI. RESULTS: The hCRHtest was performed mainly for the differential diagnosis of ACTH-dependent CS or adrenal lesions (P = .048). PeakACTH and peakcortisol were higher in CD, and ∆%ACTH and ∆%cortisol were able to differentiate CD from EAS with a sensitivity and specificity greater than 80%. In patients with low (< 10 pg/mL) or indeterminate (10-20 pg/mL) basalACTH levels, an absent or reduced peakACTH response was able to differentiate adrenal from ACTH-dependent forms. PeakACTH and peakcortisol after hCRHtest were lower in pseudo-CS than in CD, but ∆%ACTH and ∆%cortisol were similar. The role of hCRHtest in patients with AI was limited. CONCLUSIONS: The hCRHtest test is the mainstay of the differential diagnosis of ACTH-dependent CS. It is also useful for pointing to a diagnosis of CD in the event of bilateral adrenal masses, and in patients with low basalACTH.

Digital analysis of hormonal immunostaining in pituitary adenomas classified according to WHO 2017 criteria and correlation with preoperative laboratory findings.

OBJECTIVE: The authors sought to evaluate clinical and laboratory data from pituitary adenoma (PA) patients with functioning PA (associated with acromegaly [n = 10] or Cushing disease [n = 10]) or nonfunctioning PA (NFPA; n = 10) that were classified according to 2017 WHO criteria (based on the expression of the transcription factors pituitary-specific positive transcription factor 1 [Pit-1], a transcription factor member of the T-box family [Tpit], and steroidogenic factor 1 [SF-1]) and to assess the immunostaining results for growth hormone (GH) and adrenocorticotropic hormone (ACTH) in the corresponding tumors. METHODS: Clinical and laboratory data were collected retrospectively. The percentage of tumoral cells positive for Pit-1, Tpit, or SF-1 was assessed and ImageJ software was used to evaluate immunopositivity in PAs with 2 different antibodies against GH (primary antibody 1 [AbGH-1] and primary antibody 2 [AbGH-2]) and 2 different antibodies against ACTH (primary antibody 1 [AbACTH-1] and primary antibody 2 [AbACTH-2]). RESULTS: Cells with positive Pit-1 staining were more frequently observed in lesions from patients with acromegaly (acromegaly group) than in lesions from patients with Cushing disease (Cushing group; p < 0.001) and those from patients with NFPA (NFPA group; p < 0.001). The percentage of Tpit-positive cells was higher in the Cushing group than in the acromegaly (p < 0.001) and NFPA (p < 0.001) groups. No difference was detected regarding SF-1 frequency among all groups (p = 0.855). In acromegalic individuals, GH immunostaining levels varied depending on the antibody employed, and only one of the antibodies (AbGH-2) yielded higher values in comparison with the values for NFPA patients (p < 0.001). For all of the antibodies employed, no significant correlations were detected between GH tissue expression and the laboratory data (serum GH vs AbGH-1, p = 0.933; serum GH vs AbGH-2, p = 0.853; serum insulin-like growth factor-1 [IGF-1] vs AbGH-1, p = 0.407; serum IGF-1 vs AbGH-2, p = 0.881). In the Cushing group data, both antibodies showed similar ACTH tissue expression, which was higher than that obtained in the NFPA group (p < 0.001). There were no significant associations between ACTH immunohistochemical findings and ACTH serum levels (serum ACTH vs AbACTH-1, p = 0.651; serum ACTH vs AbACTH-2, p = 0.987). However, ACTH immunostaining evaluated with AbACTH-1 showed a significant correlation with 24-hour urinary cortisol (24-hour cortisol vs AbACTH-1, p = 0.047; 24-hour cortisol vs AbACTH-2, p = 0.071). CONCLUSIONS: Immunostaining for Pit-1 and Tpit accurately identified lesions associated with acromegaly and Cushing disease, respectively. Conversely, SF-1 did not differentiate NFPA from lesions of the other two groups. Regarding hormonal tissue detection, results of the current investigation indicate that different antibodies may lead not only to divergent immunohistochemical results but also to lack of correlation with laboratory findings. Finally, PA classification based on transcription factor expression (Pit-1, Tpit, and SF-1), as proposed by the 2017 WHO classification of pituitary tumors, may avoid the limitations of PA classification based solely on digital immunohistochemical detection of hormones.

Non-invasive Diagnostic Strategy in ACTH-dependent Cushing's Syndrome.

CONTEXT: Inferior petrosal sinus sampling (IPSS) is used to diagnose Cushing's disease (CD) when dexamethasone-suppression and CRH tests, and pituitary magnetic resonance imaging (MRI), are negative or give discordant results. However, IPSS is an invasive procedure and its availability is limited. OBJECTIVE: To test a noninvasive diagnostic strategy associated with 100% positive predictive value (PPV) for CD. DESIGN: Retrospective study. SETTING: Two university hospitals. PATIENTS: A total of 167 patients with CD and 27 patients with ectopic ACTH-syndrome investigated between 2001 and 2016. MAIN OUTCOME MEASURE(S): Performance of a strategy involving the CRH and desmopressin tests with pituitary MRI followed by thin-slice whole-body computed tomography (CT) scan in patients with inconclusive results. RESULTS: Using thresholds of a cortisol increase > 17% with an ACTH increase > 37% during the CRH test and a cortisol increase > 18% with an ACTH increase > 33% during the desmopressin test, the combination of both tests gave 73% sensitivity and 98% PPV of CD. The sensitivity and PPV for pituitary MRI were 71% and 99%, respectively. CT scan identified 67% EAS at presentation with no false-positives. The PPV for CD was 100% in patients with positive responses to both tests, with negative pituitary MRI and CT scan. The Negative Predictive Value was 100% in patients with negative responses to both tests, with negative pituitary MRI and positive CT scan. Using this strategy, IPPS could have been avoided in 47% of patients in whom it is currently recommended. CONCLUSIONS: In conjunction with expert radiologic interpretation, the non-invasive algorithm studied significantly reduces the need for IPSS in the investigation of ACTH-dependent Cushing's syndrome.

Persistent cortisol response to desmopressin predicts recurrence of Cushing's disease in patients with post-operative corticotropic insufficiency.

OBJECTIVE: Cushing's disease (CD) may recur despite corticotropic insufficiency (COI) following pituitary surgery. The predictive value of the desmopressin test (DT) for recurrence in this setting remains controversial. We have evaluated whether the disappearance of the response to DT predicts a low probability recurrence in a large cohort of patients with post-operative COI. DESIGN: Multicentre retrospective study. METHODS: Ninety-five patients with CD (women 82%, age 41 ± 14 years), responding preoperatively to DT and with early post-operative COI (08 00 am cortisol: <138 nmol/L), underwent a DT within 3 months post-surgery. Association between DT findings and the prediction of recurrence was tested using regression and ROC analyses. RESULTS: Recurrence occurred in 17/95 patients within 29 to 91 months. The cortisol peak (327, 95% CI (237-417) vs 121 (79-164) nmol/L, P = 0.0001) and absolute increment during DT (208 (136-280) vs 56 (22-90) nmol/L, P = 0.005) were greater in the recurrence vs remission group. Cortisol peak (AUC: 0.786 (0.670-0.902)) and increment (0.793 (0.672-0.914)) yielded a higher prognostic performance for recurrence than did the early post-operative 08 00 am cortisol (0.655 (0.505-0.804)). In the context of COI, cortisol peak >100 nmol/L and increment >30 nmol/L had a high negative predictive value (94, 95% CI (88-100) and 94, (88-100), respectively). Patients with a cortisol peak ≤100 nmol/L (vs >100) or an increment ≤30 nmol/L (vs >30) were less likely to have CD recurrence (odds ratios: 0.12, 95% CI (0.03-0.41) and 0.11 (0.02-0.36), respectively). CONCLUSION: The disappearance of the response to the post-operative DT was independently associated with a lower odds of CD recurrence and offers an incremental prognostic value, which may help to stratify patients with COI and refine their follow-up according to the risk of recurrence.

A liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based assay to profile 20 plasma steroids in endocrine disorders.

Background: Liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based assays are employed in more and more clinical laboratories to quantify steroids. The steroid quantification by LC-MS/MS shows great value in screening or diagnosing endocrine disorders; however, the number of functional steroids included in the LC-MS/MS methods is still limited. Methods: Here, we describe the performance and validation of a 20-steroid plasma panel by LC-MS/MS. The panel included progestogens (including mineralocorticoids and glucocorticoids), androgens and estrogens biosynthesized in steroid metabolic pathways. The LC-MS/MS method was validated according to guidance documents, and subsequently employed to profile steroid changes in endocrine disorders. Results: Using LC-MS/MS, 20 steroids were separated and quantified in 8 min. Coefficients of variation (CVs) of the 20 analytes at the lower limit of quantification (LLoQ) were all less than 15% (ranging from 1.84% to 14.96%). The linearity of the assay was demonstrated by all the R2 values greater than 0.995. Individual plasma steroids changed significantly in patients with subclinical Cushing's syndrome (SCS) and polycystic ovary syndrome (PCOS) - 17-hydroxypregnenolone (17-OH-PR), testosterone (T) and dihydrotestosterone (DHT) were significantly decreased in SCS patients, while in PCOS patients, pregnenolone, corticosterone (CORT), androstenedione (A4) and T were significantly increased and DHT was decreased. Conclusions: The LC-MS/MS method we developed for the quantification of 20 plasma steroids is clinical practicable. The steroid profiling data using this assay indicate its screening value for endocrine disorders. To further explore the value of the assay, more investigations are however needed.