ECE2008 Poster Presentations Paediatric endocrinology (26 abstracts)
Endocrinology Unit, University of Padua, Padua, Italy.
In the diagnosis of Cushings disease (CD) desmopressin (dDAVP) stimulation test may be a convenient and more readily available alternative to CRH test; however the sensibility and specificity of ACTH response to dDAVP test has been reported in adult patients inferior to CRH test. In childhood patients with CD there are no data for the use of dDAVP test in this clinical setting. We studied 9 patients ranging in age from 11 to 19 years (7 females and 2 males) with a suspected diagnosis of CD. Preoperative endocrine assessment included CRH, dDAVP, overnight 8 mg dexamethasone tests. CRH and dDAVP tests (positive if ACTH and cortisol levels were respectively more than 50% and 20% of the baseline) resulted both positive in 8/9 cases but a more relevant mean increase has been found for ACTH levels after dDAVP stimulation. In all patients we observed a positive response (drop in cortisol levels more than 50% of baseline values) to the dexamethasone test. At MRI scans 6 patients presented a normal pituitary gland 3 a microadenoma. All the patients underwent transphenoidal neurosurgery that was successful in 7/9 (at hystology 6 adenomas and 1 normal pituitary tissue), the other 2 patients underwent pituitary radiotherapy. Conclusions: In children and adolescents with CD a same percentage (88%) of positive response to dDAVP and CRH stimulation tests was observed. Moreover an high percentage of negative MRI scans was found and in these cases the combined positive response to the CRH and dDAVP stimulation tests, and particularly the marked response to the latter, were useful tools in the diagnosis of CD