Background: The main cause of secondary adrenal insufficiency (SAI) in children is prolonged treatment with exogenous corticosteroids. plasma cortisol (PC) levels after administration of ACTH is the most used indicator of adrenal function in clinical practice. However, salivary cortisol (SC) levels is emerging as an alternative technique in the diagnosis of adrenal pathology, especially useful in the paediatric population because it is a simple noninvasive test.
Objective and hypotheses: To evaluate the correlation between PC and SC, to assess the usefulness of salivary determination as a diagnostic parameter in children with suspected iatrogenic SAI.
Method: Prospective 2 years study (January 2014January 2016) in patients 018 years of age treated with corticosteroids for more than 15 days. Determination of PC and SC at baseline and after administration of ACTH 1 mcg intramuscular (at 30, 60 and 90 min).
Results: We analysed 60 samples (plasma and salivary) of 15 studies of ten patients (two ♂ / eitht ♀) with a mean age of 12 years (range: 3.616.5), with different underlying pathologies, studied for suspected SAI in the context of prolonged corticosteroid therapy. The Pearson coefficient showed a direct correlation between plasma and SC levels (r=0.649, P<0.001). All our patients with any determination of PC> 18 mcg/dl (n=5) had a peak SC> 0.58 mcg/dl (ROC curve, specificity 99.9%, sensitivity 99.9%).
Conclusion: SC is a less invasive test, easier and quicker to realise that PC appears to reflect the levels of free PC it could replace the PC as diagnostic method for iatrogenic SAI in children. In our study, a value of SC> 0.58 mcg/dl was able to discriminate patients without SAI.
01 - 03 Oct 2015
European Society for Paediatric Endocrinology