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Objective Growth hormone ( GH) and insulin-like growth factor I ( IGF- I) are the principal biomarkers used to assess disease activity in acromegaly, and any discrepancy between them renders interpretation of results inconclusive. Purpose of this study was to assess the frequency of this discrepancy and identify parameters that might affect its occurrence. Design A systematic review of MEDLINE and Scopus was performed (1987-2013) followed by a meta-analysis to address the frequency of discrepant results between GH and IGF- I levels. Meta-regression and subgroup analyses were performed assessing the effects of the year of publication, the different types of GH testing and GH assays used, as well as the impact of treatment with somatostatin analogues ( SSAs) on the occurrence of this discrepancy. Results The analysis retrieved 39 eligible studies totalling 7071 patients. The pooled discordance rate between GH and IGF- I was 25·7% (95% CI: 22·3-29·4), and the predominant format was that of elevated IGF- I with normal GH levels (15·3%, 95% CI: 12·5-18·7). No significant correlation between the discordance rate and the year of publication was shown; whereas, the use of ultrasensitive GH assays resulted in higher discordance rates (30·7%, 95% CI: 25·9-35·9 vs 19·8%, 95% CI: 14·1-27·2, P = 0·04) as did treatment with SSAs (32·5%, 95% CI: 27·8-37·4) vs (21·6%, 95% CI: 17·8-25·6, P = 0·001). Conclusions Discrepancy between GH and IGF- I results is encountered in a quarter of treated patients with acromegaly, especially when using ultrasensitive GH assays or in patients receiving SSAs, a fact that the clinician should take into consideration when making clinical decisions. [ABSTRACT FROM AUTHOR]

With the advent of modern imaging modalities, endocrine incidentalomas are increasingly being discovered. We aimed to investigate the presence of pituitary incidentalomas (PI) in patients with adrenal incidentalomas (AI), and identify potential metabolic correlates in this cohort. 26 patients (18 females) with AI discovered on abdominal computerized tomography were studied. All patients underwent pituitary magnetic resonance imaging (MRI) and endocrine investigations to evaluate functional adrenal pathology, anterior pituitary hormonal status, insulin-resistance indices and presence of metabolic syndrome. Pituitary MRI revealed a microadenoma and a 4 × 5 mm cyst in 1 patient respectively, and an empty sella in 4 (2 partial) patients. Overall, 6/26 (23 %) patients with an AI had evidence of pituitary imaging pathology but only 8 % had a PI; none had any evidence of abnormalities in pituitary function. Subclinical hypercortisolism was the only hyperfunctional status detected in 4 patients with AI but was unrelated to the pituitary findings. No abnormality of insulin secretion and action was found between patients with or without pituitary pathology. In the present study 23 % of patients with AI had some alteration in pituitary morphology, and 2 a PI without accompanying pituitary hormonal deficit or metabolic derangement. Further studies are required to address this issue and identify a potential pathogenetic mechanism. [ABSTRACT FROM AUTHOR]