title: Standard and low-dose short adrenocorticotropin test compared with insulin-induced hypoglycemia for assessment of the hypothalamic-pituitary-adrenal axis in children with idiopathic multiple pituitary hormone deficiencies.
abstract: Insulin-induced hypoglycemia (IIH) is the gold standard test for assessment of the integrity of the hypothalamic-pituitary-adrenal (HPA) axis, but it may be hazardous. We sought to determine whether the standard (250 micrograms) or low-dose (1 microgram/1.73 m2) short ACTH test can replace IIH in patients with idiopathic multiple pituitary hormone deficiencies (MPHD). Three groups of subjects were studied: 1) control group, children with early or accelerated puberty and no other evidence of adrenal or pituitary pathology (n = 13, age 10.1 +/- 2.2 yr, 3 males); 2) patients with idiopathic hypothalamic pituitary insufficiency and either isolated GH deficiency or MPHD and preserved HPA function (n = 20, age 13.7 +/- 4.4 yr, 13 males); and 3) MPHD patients with impaired HPA axis function (n = 10, age 16.8 +/- 4.8 yr, 9 males). IIH and the 250 micrograms and 1 microgram/1.73 m2 ACTH tests were performed in groups 2 and 3; group 1 underwent only the ACTH tests. Pass peak cortisol level was defined as 520 nmol/L. No significant difference was noted between the standard and low-dose tests in the 30-min cortisol response to ACTH. Basal and peak cortisol levels attained on both ACTH tests were similar in groups 1 and 2 and significantly lower in group 3 (P < 0.0001). Both the 250 and 1 microgram ACTH tests were highly correlated with IIH (r = 0.71, P < 0.0001 for the 250 micrograms, r = 0.7, P < 0.0001 for the 1 microgram, n = 30), and both demonstrated high sensitivity (90% each) and specificity (100% and 90%, respectively) compared with IIH. We conclude that in idiopathic MPHD patients, both the standard and low-dose ACTH tests are equivalent to IIH in detecting HPA insufficiency. We suggest that they can replace IIH as a screening test for the integrity of the HPA axis in children with suspected MPHD.
authors.affiliation: Institute for Endocrinology and Diabetes, Schneider Children's Medical Center of Israel, Petah Tiqva, Israel.
authors.forename: N
authors.initials: N
authors.lastname: Weintrob
authors.forename: E
authors.initials: E
authors.lastname: Sprecher
authors.forename: Z
authors.initials: Z
authors.lastname: Josefsberg
authors.forename: C
authors.initials: C
authors.lastname: Weininger
authors.forename: Y
authors.initials: Y
authors.lastname: Aurbach-Klipper
authors.forename: D
authors.initials: D
authors.lastname: Lazard
authors.forename: M
authors.initials: M
authors.lastname: Karp
authors.forename: A
authors.initials: A
authors.lastname: Pertzelan
mesh_terms: D000293:Adolescent; D000324:Adrenocorticotropic Hormone / Q000172:deficiency*; D017668:Age of Onset; D000704:Analysis of Variance; D002648:Child; D005260:Female; D019382:Human Growth Hormone / Q000172:deficiency*; D006801:Humans; D006854:Hydrocortisone / Q000097:blood*; D007003:Hypoglycemia / Q000097:blood / Q000139:chemically induced; D007018:Hypopituitarism / Q000097:blood / Q000175:diagnosis*; D007030:Hypothalamo-Hypophyseal System; D007328:Insulin; D008297:Male; D010907:Pituitary Hormones / Q000172:deficiency*; D010913:Pituitary-Adrenal System
chemical_list: D007328:Insulin; D010907:Pituitary Hormones; D019382:Human Growth Hormone; D000324:Adrenocorticotropic Hormone; D006854:Hydrocortisone