Cushing's syndrome: Stepwise approach to diagnosis

From Knee Pain Consultation to Pituitary Surgery: The Challenge of Cushing Disease Diagnosis

Cushing syndrome (CS) is a rare endocrinological disorder resulting from chronic exposure to excessive cortisol. The term Cushing disease is used specifically when this is caused by excessive secretion of adrenocorticotropic hormone (ACTH) by a pituitary tumor, usually an adenoma. This disease is associated with a poor prognosis, and if left untreated, it has an estimated 5-year survival rate of 50%. We present the case of a 66-year-old female patient who received a referral to endocrinology for an evaluation of obesity due to right knee arthropathy. Taking into consideration her age, she was screened for osteoporosis, with results that showed diminished bone density. Considering this, combined with other clinical features of the patient, suspicion turned toward hypercortisolism. Laboratory findings suggested that the CS was ACTH-dependent and originated in the pituitary gland. After a second look at the magnetic resonance imaging results, a 4-mm lesion was identified on the pituitary gland, prompting a transsphenoidal resection of the pituitary adenoma.

Utility of Simple and Non-Invasive Strategies Alternative to Inferior Petrosal Sinus Sampling and Peripheral CRH Stimulation in Differential Diagnosis of ACTH-Dependent Cushing Syndrome

We aimed to evaluate the utility of simple, cost-effective, and non-invasive strategies alternative to BIPSS and peripheral CRH stimulation in differential diagnosis of ACTH-dependent CS. First, we performed ROC analysis to evaluate the performance of various tests for differential diagnosis of ACTH-dependent CS in our cohort (CD, n=76 and EAS, n=23) and derived their optimal cut-offs. Subsequently, combining various demographic (gender), clinical (hypokalemia), biochemical (plasma ACTH, HDDST, peripheral CRH stimulation) and imaging (MRI pituitary) parameters, we derived non-invasive models with 100% PPV for CD. Patients with pituitary macroadenoma (n=14) were excluded from the analysis involving non-invasive models. Relative percent ACTH (AUC: 0.933) and cortisol (AUC: 0.975) increase on peripheral CRH stimulation demonstrated excellent accuracy in discriminating CD from EAS. Best cut-offs for CD were plasma ACTH<97.3 pg/ml, HDDST≥57% cortisol suppression, CRH stimulation≥77% ACTH increase and≥11% cortisol increase. We derived six models that provided 100% PPV for CD and precluded the need for BIPPS in 35/85 (41.2%) patients with ACTH-dependent CS and no macroadenoma (in whom BIPSS would have otherwise been recommended). The first three models included basic parameters and avoided both peripheral CRH stimulation and BIPSS in 19 (22.4%) patients, while the next three models included peripheral CRH stimulation and avoided BIPSS in another 16 (18.8%) patients. Using simple and non-invasive alternative strategies, BIPSS can be avoided in 41% and peripheral CRH stimulation in 22% of patients with ACTH-dependent CS and no macroadenoma; such patients can be directly referred for a pituitary surgery.

Pediatric Macrocorticotropinoma: Do They Differ from Microcorticotropinoma?

INTRODUCTION

Cushing's disease (CD) due to macrocorticotropinoma (MC) in children and adolescents is a rare entity with limited information regarding its characteristics. The objective of the study is to describe the clinical, biochemical, imaging, management, outcome, and genetic characteristics of children and adolescents with CD due to MC and compare them with those of microcorticotropinoma (mc).

METHODS

This retrospective study was conducted at a single tertiary care center. Thirty-two patients with CD and MC (maximum tumor dimension ≥10 mm on imaging) and 65 patients with mc (<10 mm on imaging) aged ≤20 years at presentation were enrolled.

RESULTS

Nineteen girls and 13 boys with MC presented at a median (IQR) age of 14.5 (12.0-17.9) years. Patients with MC had higher body mass index-standard deviation score (BMI-SDS) (3.70 ± 2.60 vs. 2.59 ± 2.01, p = 0.04), more frequent neuro-ophthalmic symptoms (25% vs. 9% p = 0.04) and short stature (59% vs. 34%, p = 0.049) but less frequent livid striae (53% vs. 77%, p = 0.01), hypokalemia (12% vs. 36%, p = 0.04), and lower cortisol (nmol/L) to corticotropin (pmol/L) ratio (41.20 vs. 55.74, p = 0.04) than those with mc. The remission (59% vs. 64%, p = 1.0) and relapse (53% vs. 37%, p = 0.26) rates after first-line surgery and remission rate after radiotherapy (RT) were comparable between the two cohorts, whereas time to remission after RT (27 vs. 13 months, p = 0.05) was longer in the MC group. A patient with MC had a pathogenic germline variant in CDH23.

CONCLUSION

In this large monocentric series of pediatric CD, frequent mass effect symptoms and short stature, higher BMI-SDS, less frequent livid striae, and hypokalemia with lower effective cortisol secretion characterize the MC cohort. The outcomes of surgery and RT were similar between the groups except for a longer time to remission after RT in the MC cohort. Germline variants are rare (4%) in pediatric MC.

Cushing Syndrome in a Pediatric Patient with Topical Steroid Overuse

Cushing syndrome is a state of hypercortisolism from exogenous or endogenous exposure to glucocorticoids resulting in various clinical manifestations. In this case report, we present a case of a 15-month-old child who presented with cushingoid facies due to over-the-counter misuse of a very potent topical steroid (clobetasol 0.05%) for suspected scabies. Laboratory measurement of urinary free cortisol level was low, and 8 : 00 am basal cortisol level was measured, which was decreased, which confirmed the diagnosis of Cushing syndrome due to exogenous source. Over-the-counter topical steroids should not be used, and one should always consult a registered medical practitioner before using such products. Physicians when prescribing topical steroids should warn patients about the potential side effects of prolonged use of topical steroids.

ACTH-independent Cushing's syndrome due to bilateral adrenocortical adenoma: A case report

The chronic excess of glucocorticoids results in Cushing's syndrome. Cushing's syndrome presents with a variety of signs and symptoms including: central obesity, proximal muscle weakness, fatigue striae, poor wound healing, amenorrhea, and others.

ACTHindependent Cushing's syndrome is usually due to unilateral adenoma. A rare cause of it is bilateral adrenal adenomas.

In this paper we report a case of a 43-year-old woman with Cushing's syndrome due to bilateral adrenal adenoma.

Bilateral Inferior Petrosal Sinus Sampling in Corticotropin-Dependent Cushing's Syndrome: A Single Center Experience from Western India

OBJECTIVE

Efficacy of bilateral inferior petrosal sinus sampling (BIPSS) in corticotropin-dependent Cushing's syndrome (CS) for localization and lateralization of excess adrenocorticotropic hormone (ACTH) source, as compared to high-dose dexamethasone suppression test (HDDST) and magnetic resonance imaging (MRI) pituitary, respectively.

METHODOLOGY

Thirteen patients with clinically and biochemically confirmed CS underwent HDDST, MRI pituitary, and BIPSS by an experienced team of intervention neurologist, neurosurgeon, and endocrinologist using percutaneous femoral vein approach.

RESULTS

Of 13 patients (11 adults and two children) who underwent BIPSS, raised central to peripheral ACTH ratio was achieved in 12 cases, remaining one case being ectopic ACTH secretion (EAS). However, inter IPS gradient >1.4 was achieved in 11 (91.6%) of 12 Cushing's disease (CD) cases before vasopressin stimulation; and in 9 (75%) of 12 CD cases after vasopressin stimulation (P-value 0.583). HDDST suppression of more than 50% was present in only ten cases with CD, falsely negating CD in two cases (16.6%), sensitivity 83.3% and specificity 100%. MRI sella demonstrated pituitary microadenoma in 12 cases and macroadenoma in one case. Lateralization by BIPSS and MRI was concordant in 7 (58.3%) out of 12 cases with CD, with rate of remission after transsphenoidal surgery being higher in patients with concordant lateralization by BIPSS and MRI.

CONCLUSIONS

BIPSS is an important investigation to distinguish CD and EAS. BIPSS was superior to HDDST for confirming the source of excess ACTH. Our findings favor the use of BIPSS for localization and pituitary MRI for lateralization of microadenoma.

Mania as Debut of Cushing's Syndrome

This is a case of a patient affected by Cushing syndrome that was admitted at the hospital due to hormonal problems. He had presented psychiatric symptoms that were mistakenly considered not directly connected to the pathology causing the clinical condition, but a mere psychological reaction to it.

Adrenal cortical hyperplasia: diagnostic workup, subtypes, imaging features and mimics

Adrenal cortical hyperplasia manifests radiologically as a non-malignant growth, or enlargement, of the adrenal glands, specifically the cortex, although the cortex cannot be definitively identified by conventional imaging. Controlled by the pituitary gland, the adrenal cortex drives critical processes, such as the production of cortisol, mineralocorticoid and sex hormones. Any disruption in the multiple enzymes and hormones involved in these pathways may cause serious or life-threatening symptoms, often associated with anatomical changes in the adrenal glands. Diagnosis and treatment of adrenal cortical hyperplasia requires a thorough clinical evaluation. As imaging has become more robust so has its role in the diagnosis and treatment of adrenal conditions. CT has been the primary modality for adrenal imaging owing to reproducibility, temporal and spatial resolution and broad access. MRI serves a complimentary role in adrenal imaging and can be used to further evaluate indeterminate CT findings or serve as an adjunct tool without the use of ionizing radiation. Ultrasound and fluoroscopy (genitography) are most commonly used in children and foetuses to evaluate congenital adrenal hyperplasia. This article will discuss the clinical presentation, laboratory workup and imaging features of adrenal cortical hyperplasia, both congenital and acquired.

Investigation for Paediatric Cushing's Syndrome Using Twenty-Four-Hour Urinary Free Cortisol Determination

OBJECTIVE

Paediatric Cushing's syndrome (CS) remains a challenge to diagnose and exclude. We assessed the accuracy of 24-hour urinary free cortisol (UFC) determination in children referred for suspected CS.

DESIGN

We conducted a retrospective study of paediatric patients referred to our centre with suspected CS between 1982 and 2014.

PATIENTS

Of 66 subjects (mean age 12.9 years; range 4.4-16.9), there were 47 cases of CS (29 males), which included Cushing's disease (CD; 39 patients, 25 males), primary pigmented nodular adrenocortical disease (8 patients, 4 males) and 19 'controls' (6 males) in whom the diagnosis of CS was excluded.

MEASUREMENTS

The subjects had between one and five 24-hour UFC collections analysed by radioimmunoassay, chemiluminescent immunoassay or liquid chromatography-mass spectrometry. The data were normalised, corrected for body surface area (m2) and assessed using receiver operating characteristic analysis and an independent two-tailed t test.

RESULTS

The diagnostic accuracy of 24-hour UFC for CS was excellent (area under the curve 0.98, 95% CI 0.946-1.00, sensitivity 89%, specificity 100%).

CONCLUSIONS

Twenty-four-hour UFC is a reliable and practical investigation with high diagnostic accuracy for paediatric CS. However, further investigations may be required if the UFC is normal but there is a high diagnostic suspicion of CS.

Cushing's syndrome presenting as treatment-resistant bipolar affective disorder: A step in understanding endocrine etiology of mood disorders

Cushing's syndrome (CS) is the multisystem disorder which is due to cortisol excess. It is very difficult to diagnose in early stages, especially when psychiatric manifestations are the predominant complaints. It could result in significant morbidity and mortality. We report a case of resistant bipolar affective disorder secondary to CS. Early diagnosis and treatment will lead to better functional outcome and prevention of neurocognitive side-effects of excessive cortisol.