Endocrine Abstracts

Background: Growth hormone deficiency (GHD) is a rare disorder characterized by pronounced and symptomatic hypo secretion of growth hormone (GH) from the anterior pituitary gland. Biochemical tests are used as part of the diagnosis in both children and adults but controversies remain as regards whom, when, and how to test, and also how to interpret a given biochemical test result.

Aim: To map the current clinical practice of GHD diagnosing in children and adults.

Methods: A scientific committee (SC) composed of five members of the Growth Hormone Research Society (GRS) initiated a Delphi survey of the diagnosis of GH deficiency in children and adults. Dedicated pediatric (n= 18) and adult (n= 25) endocrinologists from fourteen different countries participated in the survey and rated their extent of agreement to 61 statements using a Likert-type-scale (1-7). Consensus was defined as ≥ 80% of panelists rating either ≥5 (agreement) or ≤3 (disagreement).

Results: Consensus was reached in 62% (38/61) of the statements. There was agreement to test for GHD in an appropriate clinical context such as neonates with persistent hypoglycemia and prolonged jaundice, growth deceleration and short stature in children, and overt pituitary disease in adults. Notwithstanding this, consensus was not reached regarding whether or not to test e. g. short children with obesity or adult patients without a classic phenotype. Low IGF-I levels were considered diagnostic in panhypopituitary children and adults. There was consensus to recommend the arginine stimulation test for the diagnosis of GHD in children whereas the insulin tolerance test (ITT) was recognized as the gold standard in adults. Controversy persisted regarding the utility of the macimorelin stimulation test in both children and adults. A stimulated GH cut-off < 3 µg/l was consistent with complete GHD in children, whereas assay-specific cut-offs were recommended in adults.

Conclusion: This Delphi survey reveals consensus (62%) but also considerable lack of consensus (38%) among clinical experts about diagnosing GHD in children and adults. Major areas of disagreement comprised both whom and how to test.