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Familial pituitary adenomas are found in multitumoral syndromes such as multiple endocrine neoplasia type 1 (NEM1) and type 4 (NEM4) and the Carney complex (CNC); it remains at present the only known condition in the category of familial isolated pituitary adenomas (FIPA). Familial adenomas account for 3-5% of all pituitary adenomas. Their pathogenesis is known in part: mutations of the menin gene in NEM1 (80%), of the CDKN1B gene in NEM4 (several cases described), of the PRKR1A gene in CNC (50%) and the AIP gene in 15% of FIPA cases (50% of the FIPA cases with a homogeneous somatotropic phenotype). The clinical course of familial adenoma with NEM1 or FIPA is more aggressive than that of sporadic adenoma, with more macroadenomas and more patients diagnosed younger. Familial pituitary adenomas are distinguished from the sporadic forms in their genetic, epidemiologic and clinical characteristics. They require a differentiated management, especially concerning screening.

Prevalence:The prevalence of pituitary tumors has been a topic of controversy for many years. Autopsy and radiological series show that pituitary incidentalomas may be present in one of six people. Recent epidemiological data suggest that clinically apparent pituitary adenomas have a prevalence of approximately one in 1,000 people in the general population. The disconnect between these two prevalence rates underlines the common clinical quandary of how to manage pituitary incidentalomas, particularly those lacking clinical signs/symptoms or hormonal abnormalities. Management:The natural history of incidentalomas suggests that periodic hormonal, clinical and radiological follow-up is the optimal approach. In the absence of tumor growth or relevant symptoms, screening can be continued intermittently or curtailed based on the clinical judgment of the physician. In the presence of hormonal hypersecretion, the management of pituitary incidentalomas, whether they are micro- or macroadenomas, should follow accepted clinical guidelines. For incidental pituitary macroadenomas without hormonal hypersecretion, clinical management should also include assessments for visual field impairment or hypopituitarism. In such cases, regular radiological and hormonal follow-up is required to identify tumor growth or the appearance of new symptoms. In the presence of tumor growth or new hormonal abnormalities, surgical options should be considered and discussed with the patient.

ObjectiveGenetic disorders of calcium metabolism arise in a familial or sporadic setting. The calcium-sensing receptor (CASR) plays a key role in maintaining calcium homeostasis and study of theCASRgene can be clinically useful in determining etiology and appropriate therapeutic approaches. We report two cases of novelCASRgene mutations that illustrate the varying clinical presentations and discuss these in terms of the current understanding of CASR function.Patients and methodsA 16-year-old patient had mild hypercalcemia associated with low-normal urinary calcium excretion and normal-to-high parathyroid hormone (PTH) levels. Because of negative family history, familial hypocalciuric hypercalcemia was originally excluded. The second patient was a 54-year-old man with symptomatic hypocalcemia, hyperphosphatemia, low PTH, and mild hypercalciuria. Familial investigation revealed the same phenotype in the patient's sister. The coding region of theCASRgene was sequenced in both probands and their available first-degree relatives.ResultsThe first patient had a novel heterozygous inactivatingCASRmutation in exon 4, which predicted a p.A423K change; genetic analysis was negative in the parents. The second patient had a novel heterozygous activatingCASRmutation in exon 6, which predicted a p.E556K change; the affected sister of the proband was also positive.ConclusionsWe reported two novel heterozygous mutations of theCASRgene, an inactivating mutation in exon 4 and the first activating mutation reported to date in exon 6. These cases illustrate the importance of genetic testing ofCASRgene to aid correct diagnosis and to assist in clinical management.

Many causes of thyroxine malabsorption are described in the literature, but the most common cause of failure of thyroxine therapy is poor patient compliance, or pseudomalabsorption. We describe the case of a female patient who underwent total thyroidectomy for Basedow-Graves disease. Post-operatively, several treatment regimens were employed to achieve euthyroidism, but only injectable thyroxine was found to be effective. To exclude levothyroxine malabsorption, the patient was hospitalized in a hypothyroid state while a single oral test dose of levothyroxine (1000 microg) was administered. Within 4 hours a decrease of TSH level (from 59.7 to 55.6 microUI/ml) and a significant increase in free T4 levels (from 0.8 to 15.5 pg/ml) was observed, eliminating a malabsorption problem. The cause of resistance to thyroid hormone therapy was poor patient compliance, leading to the designation of this as a case of pseudomalabsorption.

SCOPO: Non e noto il rischio valvolare cardiaco associato all’esposizione a basse dosi di cabergolina nelle comuni lesioni endocrine come l’iperprolattinemia. METODI: Uno studio ecocardiografico cross-sezionale trasversale per valutare lo stato valvolare cardiaco e stato eseguito in 102 pazienti in trattamento con cabergolina per malattie endocrine e in 51 soggetti di controllo. Il trattamento con cabergolina era stato mantenuto per 12–228 mesi, con una dose cumulativa di 18–1718 mg. RISULTATI: In entrambi i gruppi era presente la stessa prevalenza di insufficienza valvolare, quasi esclusivamente di grado lieve. Due pazienti, trattati con cabergolina, presentavano insufficienza mitralica moderata; non e stata trovata alcuna relazione tra la dose di cabergolina impiegata e la presenza o la severita di insufficienza valvolare mitralica (p=NS). L’area valvolare mitralica era significativamente maggiore nel gruppo di pazienti trattati con cabergolina rispetto ai pazienti del gruppo di controllo (p=0,03). Nel 5, 9% dei soggetti trattati con cabergolina veniva osservato un ispessimento dei lembi della valvola mitralica; comunque non e stata trovata alcuna relazione con la dose cumulativa di cabergolina. In nessun paziente e stata dimostrata stenosi valvolare aortica o tricuspidale. CONCLUSIONE: Nei soggetti trattati a lungo con cabergolina alle dosi usate nella pratica endocrinologica non e stato trovato alcun aumento significativo di interessamento valvolare cardiaco. Mentre l’esposizione alla cabergolina appare sicura durante un trattamento prolungato a bassa dose, non si puo escludere completamente un’associazione tra trattamento e alterazioni subcliniche nella geometria valvolare mitralica.