title: Hypoglycemic syndrome in a patient with proinsulin-only secreting pancreatic adenoma (proinsulinoma).
abstract: We describe an unusual case of hypoglycemic syndrome in a 69-year old woman with a proinsulin-only secreting pancreatic endocrine adenoma. The clinical history was highly suggestive of an organic hypoglycemia, with normal or relatively low insulin concentrations and elevated proinsulin levels. Magnetic resonance and computed tomography of the abdomen showed a 1 cm pancreatic nodule and multiple accessory spleens. The diagnosis was confirmed by selective angiography, showing location and vascularization of the nodule, despite no response to intra-arterial calcium. After resection, the hypoglycemic syndrome resolved. The surgical specimen was comprised of a neuroendocrine adenomatous tissue with high proinsulin immunoreactivity. Study of this unusual case of proinsulinoma underlines (i) the need to assay proinsulin in patients with hypoglycemia and normal immunoreactive insulin, (ii) the differential diagnosis in the presence of accessory spleens, (iii) the unresponsiveness to intra-arterial calcium stimulation, and (iv) the extensive evaluation needed to reach a final diagnosis.
authors.affiliation: Department of Clinical and Experimental Medicine, Metabolic Division, Medical School, University of Padova, 35100 Padova, Italy.
authors.forename: Gian Paolo
authors.initials: GP
authors.lastname: Fadini
authors.forename: Alberto
authors.initials: A
authors.lastname: Maran
authors.forename: Anna
authors.initials: A
authors.lastname: Valerio
authors.forename: Francesco
authors.initials: F
authors.lastname: Meduri
authors.forename: Mariarosa
authors.initials: M
authors.lastname: Pelizzo
authors.forename: Diego
authors.initials: D
authors.lastname: Miotto
authors.forename: Cristiano
authors.initials: C
authors.lastname: Lanza
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Altavilla
authors.forename: Angelo
authors.initials: A
authors.lastname: Avogaro