Endocrine Abstracts

Introduction: Adrenal insufficiency can result in a life-threatening situation if undetected. This pathology is diagnosed by performing an ACTH-Test. Most symptoms like fatigue, loss of weight or arthralgia are rather unspecific. Therefore it is difficult to assess which patients really need an ACTH-Test. Aim of this study was to identify risk factors and indications in order to specify which patients actually require it.

Material and methods: 324 patients who received an ACTH-Test from 14th October 2011 to 2nd December 2022 were included. They were compared in terms of gender, age, BMI, blood pressure, symptoms, diagnoses, glucocorticoid medication, laboratory parameters and reasons for testing. A test result was considered as pathological if the basal cortisol level had not increased by at least 100% or >150 ng/ml after 60 minutes despite stimulation with Synacthen. Statistical analysis were executed by using SPSS.

Results: 262 of the included patients were female, 61 were male and 1 was transsexual. 87 patients had a pathological test result by definition. No patient with a previously diagnosed hyponatremia had a pathological test result. There was also no significant difference between the test groups for a low sodium value in the laboratory (9.2% (pathological) vs. 8.4% (normal), P=0.807). Statistically significant risk factors were myalgia (P=0.014), an adrenalectomy (P=0.014) and the oral intake of a cortisone-containing drug at time of the test (P=0.010), especially of prednisolone (P=0.029) and hydrocortisone (P=0.023). Statistically significant indications were an elevated ACTH value (P=0.002) and a borderline to low cortisol value (P=0.012) in the routine laboratory. It was also useful to carry out the test while discontinuing or tapering off hydrocortisone substitution (P=0.047).

Conclusions: The patient’s symptoms or clinical situation as the only reason for performing an ACTH-Test seems to be too unspecific. Other risk factors or indications like corresponding aberrances in the laboratory parameters should be taken into account.