The present data confirm the high prevalence of LV hypertrophy in primary hyperparathyroidism also in a group of patients with an asymptomatic clinical presentation. The correlation between PTH values and left ventricular mass index suggests an action of the hormone in the pathogenesis of LV hypertrophy confirmed also by the decrease of left ventricular mass index after the reduction of PTH levels. The reversal of left ventricular mass index after parathyroidectomy could affect mortality in primary hyperparathyroidism. An echocardiographic study could be suggested in the clinical work-up of primary hyperparathyroidism in order to evaluate heart involvement and the response to successful parathyroidectomy.

This study provides a clear demonstration of the current opinion that some patients with incidentally discovered adrenal adenomas may be exposed to a subtle, silent hypercortisolism. In some patients, in whom the clustering of more abnormalities in the hypothalamo-pituitary-adrenal axis occurs, subclinical Cushing's syndrome could be assumed. This term should be preferred to that of pre-clinical Cushing's syndrome since the biochemical abnormalities do not become clinically manifest, at least in the short term.

Our data in a large and modern day pHPT series, with a preponderance of asymptomatic patients, confirm increased insulin resistance and pre-valence of IGT and undiagnosed diabetes.

Our study shows that VDD occurs in about one-third of patients with pHPT resident in a Southern European area, a lower figure than previously reported. Moreover, VDD is related to a more severe bone disease, and its prevalence is higher in patients with pHPT than in healthy matched subjects.

The present data suggest that the CRH test is more reliable than the desmopressin test in determining the aetiology of Cushing's syndrome. The desmopressin test resulted in a high frequency of false positive results in patients with ectopic ACTH secondary to carcinoid tumours. This finding may be due to the capability of these tumours to express the V3 vasopressin receptor through which desmopressin acts. However, the clinical endocrinologist may be confronted with some disturbing cases which are misdiagnosed because it is almost impossible to set a diagnostic criterion providing complete specificity in the differentiation of (occult) ectopic Cushing's syndrome using either CRH or desmopressin tests.