Reliability of the diagnostic tests for Cushing's syndrome performed in a tertiary referral center

Diurnal Range and Intra-patient Variability of ACTH Is Restored With Remission in Cushing's Disease

CONTEXT

Single ACTH measurements have limited ability to distinguish patients with Cushing's disease (CD) from those in remission or with other conditions.

OBJECTIVE

To investigate the changes in ACTH levels before and after transsphenoidal surgery (TSS) to identify trends that could confirm remission from CD and help establish ACTH cutoffs for targeted clinical trials in CD.

DESIGN

Retrospective analysis of CD patients who underwent TSS from 2005 to -2019.

SETTING

Referral center.

PATIENTS

CD patients (n = 253) with ACTH measurements before and after TSS.

INTERVENTIONS

TSS for CD.

MAIN OUTCOME MEASURES

Remission after TSS.

RESULTS

Remission was observed in 223 patients after TSS. Those in remission had higher ACTH variability at AM (P = .02) and PM (P < .001) time points compared to nonremission. The nonremission group had a significantly narrower diurnal range compared to the remission group (P = <.0001). A decrease in plasma ACTH of ≥50% from mean preoperative levels predicted CD remission after TSS, especially when using PM values. The absolute plasma ACTH concentration and ratio of preoperative to postoperative values were significantly associated with nonremission after multivariable logistic regression (adj P < .001 and .001, respectively).

CONCLUSIONS

Our findings suggest that ACTH variability is suppressed in CD, and remission from CD is associated with the restoration of this variability. Furthermore, a decrease in plasma ACTH by 50% or more may serve as a predictor of remission post-TSS. These insights could guide clinicians in developing rational outcome measures for interventions targeting CD adenomas.

Cortisol and ACTH Measurements at Extubation From Pituitary Surgery Predicts Hypothalamic-Pituitary-Adrenal Axis Function

Context

Early prediction of hypothalamic-pituitary-adrenal (HPA) axis function following transsphenoidal surgery (TSS) can improve patient safety and reduce costs.

Objective

Systematic measurement of ACTH and cortisol at extubation following anesthesia to predict remission from Cushing's disease (CD) and HPA axis preservation following non-CD surgery.

Design

Retrospective analysis of clinical data between August 2015 and May 2022.

Setting

Referral center.

Patients

Consecutive patients (n = 129) undergoing TSS who had perioperative ACTH and cortisol measurements.

Interventions

ACTH and cortisol measurement at extubation. Further serial 6-hourly measurements in CD patients.

Main outcome measures

Prediction of future HPA axis status based on ACTH/cortisol at extubation.

Results

ACTH and cortisol increased sharply in all patients at extubation. CD patients (n = 101) had lower ACTH values than non-CD patients (110.1 vs 293.1 pg/mL; P < 0.01). In non-CD patients, lower plasma ACTH at extubation predicted the need for eventual corticosteroid replacement (105.8 vs 449.1 pg/mL, P < 0.01). In CD patients, the peak post-extubation cortisol at 6 hours was a robust predictor for nonremission (60.7 vs 219.2 µg/dL, P = 0.03). However, normalized early postoperative value (NEPV; the post-extubation values minus the peak preoperative CRH or desmopressin test values) of cortisol reliably distinguished nonremission earlier, at the time of extubation (-6.1 vs 5.9, P = 0.01), and later.

Conclusions

We found that at extubation following TSS, ACTH can predict the need for eventual steroid replacement in non-Cushing's patients. In patients with CD, we found a robust prediction of nonremission with NEPV cortisol at extubation and later.

Pituitary adenomas evade apoptosis via noxa deregulation in Cushing's disease

Sporadic pituitary adenomas occur in over 10% of the population. Hormone-secreting adenomas, including those causing Cushing’s disease (CD), cause severe morbidity and early mortality. Mechanistic studies of CD are hindered by a lack of in vitro models and control normal human pituitary glands. Here, we surgically annotate adenomas and adjacent normal glands in 25 of 34 patients. Using single-cell RNA sequencing (RNA-seq) analysis of 27594 cells, we identify CD adenoma transcriptomic signatures compared with adjacent normal cells, with validation by bulk RNA-seq, DNA methylation, qRT-PCR, and immunohistochemistry. CD adenoma cells include a subpopulation of proliferating, terminally differentiated corticotrophs. In CD adenomas, we find recurrent promoter hypomethylation and transcriptional upregulation of PMAIP1 (encoding pro-apoptotic BH3-only bcl-2 protein noxa) but paradoxical noxa downregulation. Using primary CD adenoma cell cultures and a corticotroph-enriched mouse cell line, we find that selective proteasomal inhibition with bortezomib stabilizes noxa and induces apoptosis, indicating its utility as an anti-tumor agent.

Asuzu et al. perform single-cell transcriptomic profiling in Cushing’s disease (CD) adenomas and find overexpression and DNA hypomethylation of PMAIP1, which encodes the pro-apoptotic protein noxa. Noxa is degraded by the proteasome. Proteasomal inhibition rescues noxa and induces apoptosis in CD.

Accuracy of Laboratory Tests for the Diagnosis of Cushing Syndrome

CONTEXT

The diagnosis of Cushing syndrome (CS) can be challenging. It remains to be determined which diagnostic tests are the most accurate.

OBJECTIVE

To summarize the accuracy of diagnostic tests for CS using contemporary meta-analytic techniques (hierarchical models).

DATA SOURCES

PubMed, Embase, Scopus, Web of Science, and the Cochrane Database of Systemic Reviews (inception until August 3, 2018).

STUDY SELECTION

Studies performed in adults that determined the accuracy of one or more diagnostic tests: overnight 1-mg dexamethasone suppression test (DST), 2-day low-dose DST (2d DST), 24-hour urinary free cortisol (UFC), late-night salivary cortisol (LNSC), midnight serum cortisol (MSC), and the dexamethasone-suppressed CRH (dex-CRH) and desmopressin (dex-DDAVP) tests.

DATA EXTRACTION

Two authors independently extracted data and performed methodological assessments.

DATA SYNTHESIS

One hundred thirty-nine studies (14 140 participants) were included in the analysis. The respective sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio (95% confidence interval [CI]) estimates include the following: DST 98.6% (96.9%-99.4%), 90.6% (86.4%-93.6%), 10.5 (7.2-15.3), and 0.016 (0.007-0.035); 2d DST 95.3% (91.3%-97.5%), 92.8% (85.7%-96.5%), 13.2 (6.47-27.1), and 0.051 (0.027-0.095); UFC 94.0% (91.6%-95.7%), 93.0% (89.0%-95.5%), 13.3 (8.47-21.0), and 0.065 (0.046-0.092); LNSC 95.8% (93.%-97.2%), 93.4% (90.7%-95.4%), 14.6 (10.3-20.7), and 0.045 (0.030-0.066); MSC 96.1% (93.5%-97.6%), 93.2% (88.1%-96.3%), 14.2 (7.96-25.2), and 0.042 (0.026-0.069); and dex-CRH 98.6% (90.4%-99.8%), 85.9% (67.6%-94.7%), 7.0 (2.80-17.6), and 0.016 (0.002-0.118). A single study evaluated dex-DDAVP. Meta-regression and a novel network meta-analytic approach suggest that DST is the most sensitive while UFC is the least sensitive.

CONCLUSIONS

All of the included diagnostic tests for CS are highly sensitive and specific. It appears that the DST is the most sensitive while the UFC is less sensitive. The specificity of all first-line tests appears comparable.

Increased adrenocorticotropic hormone (ACTH) levels predict severity of depression after six months of follow-up in outpatients with major depressive disorder

Previous studies have reported dysfunction in the hypothalamic-pituitary-adrenal (HPA) axis in patients with major depressive disorder (MDD). Outpatients diagnosed with MDD (n = 199) underwent psychological evaluation, and were followed up with a phone interview after 6 months, using the Patient Health Questionnaire (PHQ-9). At 6-month follow-up, 59 out of 199 patients with MDD were still depressed (29.5%), as shown by scores ≥ 10 on the PHQ-9. The depressed group at follow-up showed significantly higher anxiety and suicidality levels at baseline than the non-depressed group at follow-up. Among the complete blood counts, lipid profiles, and hormone levels, adrenocorticotropic hormone (ACTH) was the only parameter that was significantly increased in the still depressed group. Levels higher than 40 pg/mL of ACTH at baseline were associated with higher depression scores at follow-up. Multiple linear regression analyses revealed that ACTH and cortisol predicted depression scores at follow-up, after controlling for baseline depression scores. Increased ACTH level at baseline may predict ongoing symptoms and severity of depression at follow-up, suggesting the role of dysfunctional HPA axis in MDD prognosis.

Earlier post-operative hypocortisolemia may predict durable remission from Cushing's disease

CONTEXT

Achievement of hypocortisolemia following transsphenoidal surgery (TSS) for Cushing's disease (CD) is associated with successful adenoma resection. However, up to one-third of these patients recur.

OBJECTIVE

We assessed whether delay in reaching post-operative cortisol nadir may delineate patients at risk of recurrence for CD following TSS.

METHODS

A retrospective review of 257 patients who received 291 TSS procedures for CD at NIH, between 2003 and 2016. Early biochemical remission (serum cortisol nadir <5 μg/dL) was confirmed with endocrinological and clinical follow-up. Recurrence was detected by laboratory testing, clinical stigmata or medication dependence during a median follow-up of 11 months.

RESULTS

Of the 268 unique admissions, remission was recorded in 241 instances. Recurrence was observed in 9% of these cases with cortisol nadir ≤5 μg/dL and 6% of cases with cortisol nadir ≤2 μg/dL. The timing of hypocortisolemia was critical in detecting late recurrences. Morning POD-1 cortisol <3.3 μg/dL was 100% sensitive in predicting durable remission and morning POD-3 cortisol ≥18.5 μg/dL was 98.6% specific in predicting remote recurrence. AUROC analysis revealed that hypocortisolemia ≤5 µg/dL before 15 h (post-operative) had 95% sensitivity and an NPV of 0.98 for durable remission. Serum cortisol level ≤2 µg/dL, when achieved before 21 h, improved sensitivity to 100%.

CONCLUSIONS

In our cohort, early, profound hypocortisolemia could be used as a clinical prediction tool for durable remission. Achievement of hypocortisolemia ≤2 µg/dL before 21 post-operative hours appeared to accurately predict durable remission in the intermediate term.

Normalized Early Postoperative Cortisol and ACTH Values Predict Nonremission After Surgery for Cushing Disease

CONTEXT

Perioperative increases in adrenocorticotropic hormone (ACTH) and cortisol mimic results of corticotropin-releasing hormone (CRH) stimulation testing. This phenomenon may help identify patients with residual adenoma after transsphenoidal surgery (TSS) for Cushing disease (CD).

OBJECTIVE

To predict nonremission after TSS for CD.

DESIGN

Retrospective case-control study of patients treated at a single center from December 2003 until July 2016. Early and medium-term remission were assessed at 10 days and 11 months.

PATIENTS AND SETTING

Two hundred and ninety-one consecutive TSS cases from 257 patients with biochemical evidence of CD seen at a clinical center.

INTERVENTIONS

Normalized early postoperative values (NEPVs) for cortisol and ACTH were calculated as immediate postoperative cortisol or ACTH levels minus preoperative post-CRH-stimulation test levels.

MAIN OUTCOME MEASURES

Prediction of early nonremission was evaluated using logistic regression. Prediction of medium-term remission was assessed using Cox regression. Predictive ability was quantified by area under the receiver operating characteristic curve (AUROC).

RESULTS

NEPVs for cortisol and ACTH predicted early nonremission [adjusted odds ratio (OR): 1.1; 95% confidence interval (CI): 1.0, 1.1; P = 0.016 and adjusted OR: 1.0; 95% CI: 1.0, 1.0; P = 0.048, respectively]. AUROC for NEPV of cortisol was 0.78 (95% CI: 0.61, 0.95); for NEPV of ACTH, it was 0.80 (95% CI: 0.61, 0.98). NEPVs for cortisol and ACTH predicted medium-term nonremission [hazard ratio (HR): 1.1; 95% CI: 1.0, 1.1; P = 0.023 and HR: 1.0; 95% CI: 1.0, 1.0; P = 0.025, respectively].

CONCLUSIONS

NEPVs for cortisol and ACTH predicted nonremission after TSS for CD.

Ectopic ACTH secretion (EAS) associated to a well-differentiated peritoneal mesothelioma: case report

BACKGROUND

The association between mesotheliomas and ectopic ACTH secretion has been rarely reported; we present the first case of ectopic ACTH secretion (EAS) associated with a well-differentiated peritoneal mesothelioma in whom the high dose dexamethasone suppression test (HDDST) results and plasmatic ACTH levels were similar to those found in Cushing's disease (CD).

CASE PRESENTATION

A 43-year-old hispanic woman with a 20 year history of treatment resistant diabetes mellitus and arterial hypertension. She had a full moon face, a buffalo hump, increased volume in both supraclavicular regions, purple striae in her arms and abdomen, truncal obesity, polymenorrhea and umbilical hernia. A cortisol suppression test with low dose dexamethasone (LDDST) with a result of 16.6 μg/dL and ACTH plasma levels were measured at 32.6 pg/mL. The high dose dexamethasone test suppression percentage was 84.8% and magnetic resonance imaging (MRI) showed no evidence of pituitary alterations, computed tomography (CT) showed images suggestive of uterine fibroid and an intra-abdominal tumor that correlated with an umbilical hernia, which reinforcement after contrast. Surgery was performed, finding uterine fibroids and paracolic tumor implants as well as on the omentum, bladder, bowel, ovaries and appendix. Pathology reported a well-differentiated peritoneal mesothelioma with positive immunohistochemistry for ACTH.

CONCLUSIONS

Although most cases of ectopic secretion of ACTH derive from rapidly-developing lung tumors, with very high plasma ACTH levels and cortisol suppression percentages with high doses of dexamethasone under 60%, there is a small percentage of slow-developing, chronic tumors that are biochemically undistinguishable from Cushing's disease. Following the expert recommendations regarding imaging techniques it is possible to identify the associated tumor in most cases.