The role of corticotrophin-releasing hormone in the diagnosis of Cushing’s syndrome

Abstract

Background: Corticotrophin-releasing hormone (CRH) was identified by Vale and co-workers in 1981 and has since been used extensively in the diagnosis of ACTH-dependent Cushing's syndrome (CS). It was hoped that the CRH test would discriminate between pituitary and ectopic ACTH secretion. In adults, a rise from basal to peak plasma cortisol of R20% and ACTH of R50% is consistent with Cushing's disease (CD). Methods: Twenty-seven paediatric patients, with CD (mean ageGS.D. 13.1G3.2; range 6.4-17.8 years) were investigated in our centre between 1982 and 2005. Results: During the CRH test, all patients showed an increase in cortisol of O20% (range 106-554%). In one patient with ectopic ACTH syndrome, there was no increase in cortisol after CRH. In six paediatric patients with CS due to primary adrenal hyperplasia, no patient showed an increase in cortisol after CRH of O1%. Conclusions: A further suggested use of CRH is to increase the sensitivity of the central to peripheral and interpetrosal ratios of ACTH during inferior petrosal sinus catheterisation (IPSS). Bilateral IPSS with human CRH (hCRH) has been performed in our unit in 21 children with CD, as part of the preoperative preparation prior to trans-sphenoidal surgery (TSS). Its principal role was to identify the site of the microadenoma. Sixteen of 21 patients (76%) who underwent IPSS with hCRH were cured following TSS. In our view, the CRH test is of value during IPSS by clarifying the position of the microadenoma and in this way contributed to the overall outcome of TSS in paediatric patients with CD.

Advances in the Management of Paediatric Cushing’s Disease

“…We also perform a CRH test (1 µg/kg i.v.) and in 27 CD patients serum cortisol increased by >20% (range 106–554%) [21]. Although it is arguable that ectopic ACTH syndrome is so rare in children that the CRH test is not justified, we find an increased cortisol response contributes to the diagnosis of CD.…”

Work-up and management of paediatric Cushing's syndrome

“…and in 27 Cushing's disease patients' serum cortisol increased by more than 20% (range: 106-554%) [24]. Although [25].…”

Diagnosis and treatment of pediatric Cushing’s disease

“…We routinely perform a corticotrophin-releasing hormone (CRH) test (1 lg/kg IV); in 27 CD patients serum cortisol increased by >20% (range 106-554%) [21]. Although it is arguable that ectopic ACTH syndrome is so rare in children that the CRH test is not justified, we find that an increased cortisol response to CRH contributes to confirming the diagnosis of CD.…”