Efficacy of dexamethasone suppression test during the diagnosis of primary pigmented nodular adrenocortical disease in Chinese adrenocorticotropic hormone-independent Cushing syndrome

Adrenal Cushing's syndrome in children

Adrenal Cushing's syndrome is a rare cause of endogenous hypercortisolism in neonatal and early childhood stages. The most common causes of adrenal CS are hyperfunctioning adrenal tumours, adenoma or carcinoma. Rarer causes are primary bilateral macronodular adrenal hyperplasia (PBAMH), primary pigmented adrenocortical disease (PPNAD) and McCune Albright syndrome. The diagnosis represents a challenge for clinicians. In cases of clinical suspicion, confirmatory tests of hypercortisolism should be performed, similarly to those performed in adults. Radiological imaging should be always combined with biochemical confirmatory tests, for the differential diagnosis of adrenal CS causes. Treatment strategies for adrenal CS include surgery and in specific cases medical drugs. An adequate treatment is associated to an improvement of growth, bone health, reproduction and body composition from childhood into and during adult life. After cure, lifelong glucocorticoid replacement therapy and endocrine follow-up are required, notably in patients with Carney's complex disease.

Treatment of Primary Pigmented Nodular Adrenocortical Disease

Primary pigmented nodular adrenocortical disease (PPNAD) is a rare cause of adrenocorticotropin hormone (ACTH)-independent Cushing's syndrome (CS), which mainly occurs in children and young adults. Treatment options with proven clinical efficacy for PPNAD include adrenalectomy (bilateral or unilateral adrenalectomy) and drug treatment to control hypercortisolemia. Previously, the main treatment of PPNAD is bilateral adrenal resection and long-term hormone replacement after surgery. In recent years, cases reports suggest that unilateral or subtotal adrenal resection can also lead to long-term remission in some patients without the need for long-term hormone replacement therapy. Medications for hypercortisolemia, such as Ketoconazole, Metyrapone and Mitotane et.al, have been reported as a preoperative transition for in some patients with severe hypercortisolism. In addition, tryptophan hydroxylase inhibitor, COX2 inhibitor Celecoxib, somatostatin and other drugs targeting the possible pathogenic mechanisms of the disease are under study, which are expected to be applied to the clinical treatment of PPNAD in the future. In this review, we summarize the recent progress on treatment of PPNAD, in which options of surgical methods, research results of drugs acting on possible pathogenic mechanisms, and the management during gestation are described in order to provide new ideas for clinical treatment.

Cushing´s syndrome due to bilateral adrenal cortical disease: Bilateral macronodular adrenal cortical disease and bilateral micronodular adrenal cortical disease

Cushing´s syndrome (CS) secondary to bilateral adrenal cortical disease may be caused by bilateral macronodular adrenal cortical disease (BMACD) or by bilateral micronodular adrenal cortical disease (miBACD). The size of adrenal nodules is a key factor for the differentiation between these two entities (>1cm, BMACD and <1cm; miBACD). BMACD can be associated with overt CS, but more commonly it presents with autonomous cortisol secretion (ACS). Surgical treatment of BMACD presenting with CS or with ACS and associated cardiometabolic comorbidities should be the resection of the largest adrenal gland, since it leads to hypercortisolism remission in up to 95% of the cases. Medical treatment focused on the blockade of aberrant receptors may lead to hypercortisolism control, although cortisol response is frequently transient. miBACD is mainly divided in primary pigmented nodular adrenocortical disease (PPNAD) and isolated micronodular adrenocortical disease (i-MAD). miBACD can present at an early age, representing one of the main causes of CS at a young age. The high-dose dexamethasone suppression test can be useful in identifying a paradoxical increase in 24h-urinary free cortisol, that is a quite specific in PPNAD. Bilateral adrenalectomy is generally the treatment of choice in patients with overt CS in miBACD, but unilateral adrenalectomy could be considered in cases with asymmetric disease and mild hypercortisolism. This article will discuss the clinical presentation, genetic background, hormonal and imaging features and treatment of the main causes of primary bilateral adrenal hyperplasia associated with hypercortisolism.

Update on primary micronodular bilateral adrenocortical diseases

PURPOSE OF REVIEW

Primary micronodular bilateral adrenocortical hyperplasias (MiBAH) are rare challenging diseases. Important progress in understanding its pathophysiology and genetics occurred in the last two decades. We summarize those progress and recent data on investigation and therapy of MiBAH focusing on primary pigmented nodular adrenocortical disease (PPNAD).

RECENT FINDINGS

Larger recent cohorts of PPNAD patients from various countries have confirmed their variable Cushing's syndrome phenotypes. Age of onset is earlier than other ACTH-independent Cushing's syndrome causes and the youngest case have now occurred at 15 months. Two retrospective studies identified an increased risk of osteoporotic fractures in PPNAD as compared with other Cushing's syndrome causes. The utility of 6-day oral dexamethasone test to produce a paradoxical increase of urinary-free cortisol in PPNAD was confirmed but the mean fold of increase was of 48%, less than previously suggested. Several new genetic variants of the PRKAR1A gene have been reported in PPNAD or Carney complex (CNC). Remission of Cushing's syndrome with unilateral adrenalectomy was reported in a few patients with PPNAD.

SUMMARY

MiBAH, PPNAD and CNC are rare challenging diseases, but with combined expert clinical and genetic approaches a comprehensive investigation and prevention strategy can be offered to affected patients and families.

Adrenocortical hyperplasia: A multifaceted disease

Adrenocortical hyperplasia may develop in different contexts. Primary adrenal hyperplasia may be secondary to primary bilateral macronodular adrenocortical hyperplasia (PBMAH) or micronodular bilateral adrenal hyperplasia (MiBAH) which may be divided in primary pigmented nodular adrenocortical disease (PPNAD) and isolated micronodular adrenocortical disease (i-MAD). Both lead to oversecretion of cortisol and potentially to Cushing's syndrome. Moreover, adrenocortical hyperplasia may be secondary to longstanding ACTH stimulation in ACTH oversecretion as in Cushing's disease, ectopic ACTH secretion or glucocorticoid resistance syndrome and congenital adrenal hyperplasia secondary to various enzymatic defects within the cortex. Finally, idiopathic bilateral adrenal hyperplasia is the most common cause of primary aldosteronism. We will discuss recent findings on the multifaceted forms of adrenocortical hyperplasia.

Validity of discharge ICD-10 codes in detecting the etiologies of endogenous Cushing's syndrome

OBJECTIVE

To investigate the validity of discharge ICD-10 codes in detecting the etiology of endogenous Cushing's syndrome (CS) in hospitalized patients.

METHODS

We evaluated the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of CS etiology-related ICD-10 codes or code combinations by comparing hospital discharge administrative data (DAD) with established diagnoses from medical records.

RESULTS

Coding for patients with adrenocortical adenoma (ACA) and those with bilateral macronodular adrenal hyperplasia (BMAH) demonstrated disappointingly low sensitivity at 78.8% (95% CI: 70.1-85.6%) and 83.9% (95% CI: 65.5-93.9%), respectively. BMAH had the lowest PPV of 74.3% (95% CI: 56.4-86.9%). In confirmed ACA patients, the sensitivity for ACA code combinations was higher in patients initially admitted to the Department of Endocrinology before surgery than that in patients directly admitted to the Department of Urology (90.0 vs 73.1%, P = 0.033). The same phenomenon was observed in the PPV for the BMAH code (100.0 vs 60.9%, P = 0.012). Misinterpreted or confusing situations caused by coders (68.1%) and by the omission or denormalized documentation of symptomatic diagnosis by clinicians (26.1%) accounted for the main source of coding errors.

CONCLUSIONS

Hospital DAD is an effective data source for evaluating the etiology of CS but not ACA and BMAH. Improving surgeons' documentation, especially in the delineation of symptomatic and locative diagnoses in discharge abstracts; department- or disease-specific training for coders and more multidisciplinary collaboration are ways to enhance the applicability of administrative data for CS etiologies.

Primary pigmented nodular adrenocortical disease (PPNAD): single centre experience

Background Primary pigmented nodular adrenocortical disease (PPNAD) is a rare cause of Cushing's syndrome (CS) in childhood. We describe a case series of patients presenting at our centre along with a review of the literature. Methods A retrospective analysis of six index cases and one family were done for demographic features, hormonal profile, imaging findings, genetic mutation status, histopathologic findings and follow-up details. Diagnosis was based on biochemistry and confirmed with histopathology and or genetic mutation. All patients had suppressed 8 am adrenocorticotropic hormone (ACTH) (<10 pg/mL) despite evidence of hypercortisolism. Results The mean age in our cohort was 8.2 years (range 15 months to 20 years). All patients presented with overt CS, including one patient with cyclic Cushing's. Three patients had additional features of Carney complex (CNC). Imaging did not reveal any obvious mass lesions on computed tomography (CT), the classical beaded appearance was present in only two of the patients. Mutation analysis was positive in three patients. Five patients underwent bilateral adrenalectomy and had features of PPNAD on histopathology. Conclusions PPNAD is a rare cause of ACTH-independent CS in childhood and may signal underlying CNC. Patients with younger age of onset with overt CS may still have a mutation in the PRKAR1A gene and warrant genetic testing.

Demographic Characteristics, Etiology, and Comorbidities of Patients with Cushing's Syndrome: A 10-Year Retrospective Study at a Large General Hospital in China

PURPOSE

To investigate the demographic characteristics, etiology, and comorbidities of Cushing's syndrome (CS) patients at a large medical center in China.

METHODS

Records on CS patients discharged from 2008 to 2017 were retrieved from the hospital discharge abstract database (DAD) using ICD-10 codes. Demographic characteristics, etiology, and comorbidity data were analyzed.

RESULTS

Cushing's disease (CD) accounted for 63.0% of CS patients, followed by adrenocortical adenoma (ACA) (20.9%), primary bilateral macronodular adrenal hyperplasia (BMAH) (6.2%), ectopic ACTH syndrome (EAS) (5.9%), primary pigmented nodular adrenocortical disease (PPNAD) (1.8%), and adrenocortical carcinoma (ACC) (1.0%). CD, ACA, ACC, and PPNAD presented marked preponderances in women (4.1 : 1, 10.5 : 1, 4.3 : 1, and 2.3 : 1, respectively), while BMAH (59.8%) and EAS (51.0%) showed slightly higher preponderances in men. CD patients were younger than ACA and EAS patients (36.1 ± 12.9 years vs. 39.4 ± 12.7 years and 36.1 ± 12.9 years vs. 41.0 ± 15.8, P < 0.001); PPNAD patients were the youngest (24.2 ± 10.8 years, P < 0.001), and BMAH patients were the oldest (51.3 ± 9.9 years, P < 0.001). Hypertension, diabetes mellitus, osteoporosis without fractures, osteoporotic fractures, dyslipidemia, and fatty liver occurred more frequently in CD patients than in ACA patients (P < 0.001 for all). Osteoporotic fractures were observed more frequently in PPAND than in ACA (26.7% vs. 9.0%, P < 0.001) and BMAH (26.7% vs. 4.9%, P < 0.001) patients. EAS patients had more severe and diverse comorbidities, with higher prevalences of hypokalemia (52.0%), diabetes mellitus (61.2%), and osteoporotic fractures (28.6%). When adjusted for age, male CD patients were associated with hypertension (OR = 2.266, 95% CI: 1.524-3.371, and P < 0.001), osteoporotic fractures (OR = 2.274, 95% CI: 1.568-3.298, and P < 0.001), fatty liver (OR = 1.435, 95% CI: 1.028-2.003, and P = 0.034), and hypokalemia (OR = 1.944, 95% CI: 1.280-2.951, and P = 0.002).

CONCLUSIONS

The proposed method efficiently evaluates CS patients' epidemiological profiles using hospital DADs with ICD-10 codes and thus may enrich the limited epidemiological data and contribute to clinical practice for CS.

Comparison of two commercial quality control sera for adrenocorticotropin (ACTH) used in Elecsys® immunoassay system

OBJECTIVES

The purpose of our study was to investigate whether the storage time and temperature of internal quality control (IQC) material influence the result of ACTH in IQC measurements.

DESIGN AND METHODS

Five levels of IQC materials from two manufacturers were tested through the precision of ACTH, the three freeze/thaw cycles, and the storage time and temperature to evaluate the stability of IQC material. All commercial control materials were simultaneously tested three times a day for five consecutive days.

RESULTS

Total precision of three levels of Bio-Rad IQC sera was 13.93%, 16.45%, and 15.98%, respectively, but repeatability was <2%. The concentration of ACTH decreased by 30%-50% after 3 freeze/thaw cycles. At room temperature, the concentration of ACTH from 3 levels decreased by 16.60%, 17.98%, and 17.20%, respectively, after 0.5 hours, and 70.54%, 74.36%, and 72.03%, respectively, after 4 hours. However, after 2 hours of storage at 4°C, the decline in the measured ACTH IQC was 8.04%, 11.84%, and 10.11%, respectively. Total precision of Roche IQC was 1.17% and 1.08%, respectively. After 3 freeze/thaw cycles, the concentration of ACTH decreased <5%. After 4 hours, the change of ACTH still steadied within 5% both at the room temperature and at 4°C.

CONCLUSION

Roche is a better choice for ACTH of IQC material in Elecsys^® immunoassay system in our study. If Bio-Rad control materials be used in Elecsys^® immunoassay system for ACTH IQC testing material, it should be stored at 4°C and testing should be completed within 1 hours.