The short synacthen test: Variations in methodology and protocols in KSA

Abstract

Objectives: This study aimed to compare the current Kingdom-wide practice with our prior institutional study on use of the short synacthen test (SST), and to determine whether physician specialty or grade is associated with a tendency toward using a particular protocol. Method: We surveyed clinicians registered with the Saudi Medical Council to determine the different SST protocols used within KSA. Results: We received 162 responses, 66 (41%) from endocrinologists and the remainder from internists. A total of 61 (38%) respondents were consultants, whereas the rest were non-consultant grade. The clinicians indicated metabolic derangements, such as hypotension (78%), hyponatremia (65%), hypoglycemia (59%), and hyperkalemia (54%), as the main reasons for performing the test. Most clinicians used the SST protocol, which measures baseline serum cortisol (90%) and ACTH (78%) on the test day. A total of 75% of the physicians measured both the 30- and 60-minute serum cortisol after ACTH injection. Of these clinicians, 13% reported that the cortisol levels were below the pass threshold at 30 min but reached the pass threshold only at 60 min. The SST was normal 90% of the time when performed. A total of 93% of the clinicians considered a stimulated cortisol level of 550 nmol/L to be the threshold for normal adrenal function. Conclusion: The survey confirms that 60-min serum cortisol should be part of the SST protocol to avoid falsepositive results. Moreover, clinicians should consider other causes of these metabolic derangements before requesting a SST, particularly in patients with a low pretest probability.