The Discriminatory Value of the Low-Dose Dexamethasone Suppression Test in the Investigation of Paediatric Cushing’s Syndrome

There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

Abstract

Background: Low- and high-dose dexamethasone suppression tests (LDDST, HDDST) are used in the investigation of Cushing’s syndrome (CS). In adults with Cushing’s disease (CD), cortisol suppression during LDDST predicts suppression during the HDDST. Methods: We reviewed the results of the LDDST (0.5 mg 6 hourly × 48 h), HDDST (2.0 mg 6 hourly × 48 h) and corticotrophin-releasing hormone (CRH) test in 32 paediatric patients with CS: 24 had CD, 1 ectopic ACTH syndrome, 5 nodular adrenal hyperplasia and 2 adrenocortical tumours. Results: In CD, LDDST suppressed cortisol from 590.7 ± 168.8 (mean ± SD) to 333.7 ± 104.0 nmol/l after 48 h (0 vs. 48 h, p < 0.05; mean suppression, 45.1%; CI (30.8, 59.4%); 16/24 (66%) suppressed >30%; mean suppression 68.1%, CI (58.1, 77.9%)). The HDDST suppressed cortisol from 596.3 ± 174.5 to 47.1 ± 94.8 nmol/l after 48 h (0 vs. 48 h, p < 0.05; mean suppression, 93.5%; CI (88.2, 98.8%) with 17/24 (71%) suppressing to <50 nmol/l and 100% to <50% of baseline). In the LDDST, suppression correlated with that during the HDDST (r = +0.45, p < 0.05) with >30% suppression predicting that in the HDDST and hence CD. CRH increased cortisol by +100.3% (CI 62, 138.5%), 22/24 (91.7%) showing a >20% increase. In the other CS pathologies (n = 8) the LDDST induced no significant decrease in cortisol. Conclusion: The LDDST was of diagnostic value by discriminating between CD and other CS aetiologies. In our view the HDDST is redundant in the investigation of paediatric CS.

Related collections

Most cited references 7

Record: found
Abstract: not found
Article: not found

The Diagnosis and Differential Diagnosis of Cushing's Syndrome and Pseudo-Cushing's States

J Newell-Price (1998)

0 comments Cited 38 times – based on 0 reviews      Review now

Record: found
Abstract: found
Article: not found

Discriminatory value of the low-dose dexamethasone suppression test in establishing the diagnosis and differential diagnosis of Cushing's syndrome.

Lawrence Chew, J. P. Monson, Robin Morris … (2003)

Cushing's syndrome requires a screening test of high sensitivity, followed by biochemical evaluation of the source of the tumor when the cause is ACTH dependent. The high-dose dexamethasone suppression test is still in common use as an aid in differential diagnosis, although its value has been queried. We have routinely used the low-dose dexamethasone suppression test for many years in the diagnosis of Cushing's syndrome but noticed that patients with pituitary-dependent Cushing's syndrome or Cushing's disease, usually showed some degree of suppression of their serum cortisol, compared to those with the ectopic ACTH syndrome. We therefore analyzed retrospectively the serum cortisol responses during the low-dose dexamethasone suppression test and the high-dose dexamethasone suppression test in 245 patients with ACTH-dependent Cushing's syndrome and compared the diagnostic utility of each test either alone or in combination with a standard test using CRH. Evaluation of the serum cortisol response at 24 and 48 h during the low-dose dexamethasone suppression test correctly identified 98% of patients with ACTH-dependent Cushing's syndrome and distinguished between pituitary and ectopic causes with a sensitivity of 82% and a specificity of 79%. In the same patients, the serum cortisol response to the high-dose dexamethasone suppression test had a slightly higher sensitivity (91%) and specificity (80%). However, the combined criteria of a more than 30% suppression of serum cortisol during the low-dose dexamethasone suppression test and/or a more than 20% increase in the CRH test had a significantly higher sensitivity (97%) and specificity (94%) than either the high-dose dexamethasone or the CRH tests alone in the differential diagnosis of ACTH-dependent Cushing's syndrome. It produced equivalent information to that when high-dose and CRH test results were combined. We therefore conclude that in our patient series, the serum cortisol response during the low-dose dexamethasone suppression test is highly sensitive in diagnosing Cushing's syndrome and, combined with the results of the serum cortisol response to the CRH test, offered a safe and cost-effective test in the differential diagnosis of ACTH-dependent Cushing's syndrome. There does not appear to be any necessity for retaining the high-dose dexamethasone suppression test in this diagnostic work-up.

0 comments Cited 33 times – based on 0 reviews      Review now

Record: found
Abstract: found
Article: not found

Clinical and endocrine responses to pituitary radiotherapy in pediatric Cushing's disease: an effective second-line treatment.

Helen L. Storr, P Plowman, Paul Carroll … (2003)

Transsphenoidal surgery (TSS) is considered first-line treatment for Cushing's disease (CD). Options for treatment of postoperative persisting hypercortisolemia are pituitary radiotherapy (RT), repeat TSS, or bilateral adrenalectomy. From 1983 to 2001, we treated 18 pediatric patients (age, 6.4-17.8 yr) with CD. All underwent TSS, and 11 were cured (postoperative serum cortisol, <50 nM). Seven (39%) had 0900-h serum cortisol of 269-900 nM during the immediate postoperative period (2-20 d), indicating lack of cure. These patients (6 males and 1 female; mean age, 12.8 yr; range, 6.4-17.8 yr; 4 prepubertal; 3 pubertal) received external beam RT to the pituitary gland, using a 6-MV linear accelerator, with a dose of 45 Gy in 25 fractions over 35 d. Until the RT became effective, hypercortisolemia was controlled with ketoconazole (dose, 200-600 mg/d) (n = 4) and metyrapone (750 mg-3 g/d) +/- aminoglutethimide (1 g/d) or o'p'DDD (mitotane, 3 mg/d) (n = 3). All patients were cured after pituitary RT. The mean interval from RT to cure (mean serum cortisol on 5-point day curve, <150 nM) was 0.94 yr (0.25-2.86 yr). Recovery of pituitary-adrenal function (mean cortisol, 150-300 nM) occurred at mean 1.16 yr (0.40-2.86 yr) post RT. At 2 yr post RT, puberty occurred early in one male patient (age, 9.8 yr) but was normal in the others. GH secretion was assessed at 0.6-2.5 yr post RT in all patients: six had GH deficiency (peak on glucagon/insulin provocation, <1.0-17.9 mU/liter) and received human GH replacement. Follow-up of pituitary function 7.6 and 9.5 yr post RT in two patients showed normal gonadotropin secretion and recovery of GH peak to 29.7 and 19.2 mU/liter. The seven patients were followed for mean 6.9 yr (1.4-12.0 yr), with no evidence of recurrence of CD. In conclusion, pituitary RT is an effective and relatively rapid-onset treatment for pediatric CD after failure of TSS. GH deficiency occurred in 86% patients. Long-term follow-up suggests some recovery of GH secretion and preservation of other anterior pituitary function.

0 comments Cited 24 times – based on 0 reviews      Review now

All references

Author and article information

Journal

Journal ID (publisher-id): HRE

Journal ID (nlm-ta): Horm Res Paediatr

Journal ID (doi): 10.1159/issn.1663-2818

Title: Hormone Research in Paediatrics

Publisher: S. Karger AG

ISSN (Print): 1663-2818

ISSN (Electronic): 1663-2826

Publication date Subscription-year: 2006

Publication date (Print): March 2006

Publication date (Electronic): 29 March 2006

Volume: 65

Issue: 3

Pages: 159-162

Affiliations

Departments of ^aEndocrinology and ^bClinical Biochemistry, Barts and the London School of Medicine and Dentistry, London, UK

Article

Publisher ID: 91830 Other ID: Horm Res 2006;65:159–162

DOI: 10.1159/000091830

PubMed ID: 16514243

SO-VID: fbc86948-e41a-4859-ad39-af24102d7fdd

License:

Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher. Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug. Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.

History

Date received : 05 September 2005

Date accepted : 20 January 2006

Page count

Figures: 2, References: 13, Pages: 4

Comments

Comment on this article

Cited by 8

See all cited by

Most referenced authors 159

See all reference authors

- Version 1
- Version 1

Call for Papers: Neuro-Immune-Endocrine Facet in Infectious Disease Pathophysiology

Submit here by July 1, 2025