title: Insulin and somatostatin releasing islet cell tumor caused hypoglycemia.
abstract: We report a hypoglycemic case with normal insulin levels, which was caused by an islet cell tumor that was releasing insulin and somatostatin. A fasting test suggested the over secretion of insulin. Moreover, this hypoglycemia was enhanced by the inhibitory effect of somatostatin on the secretion of insulin counter-regulatory hormones, such as glucagon, in addition to the autonomous secretion of insulin from the tumor. In cases of hypoglycemia with apparently normal insulin levels, the measurement of somatostatin and various provocative tests are recommended. Arterial stimulation venous sampling (ASVS) was useful to detect the location of this functioning islet cell tumor.
authors.affiliation: Department of Internal Medicine 2, Shinshu University Medical School, Matsumoto.
authors.forename: Y
authors.initials: Y
authors.lastname: Karasawa
authors.forename: T
authors.initials: T
authors.lastname: Mochizuki
authors.forename: S
authors.initials: S
authors.lastname: Kawa
authors.forename: Y
authors.initials: Y
authors.lastname: Aoki
authors.forename: T
authors.initials: T
authors.lastname: Ueno
authors.forename: T
authors.initials: T
authors.lastname: Watanabe
authors.forename: S
authors.initials: S
authors.lastname: Kawasaki
authors.forename: S
authors.initials: S
authors.lastname: Miyagawa
authors.forename: N
authors.initials: N
authors.lastname: Itoh
authors.forename: C
authors.initials: C
authors.lastname: Tamai
authors.forename: A
authors.initials: A
authors.lastname: Sakurai
authors.forename: K
authors.initials: K
authors.lastname: Kiyosawa
mesh_terms: D007516:Adenoma, Islet Cell / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology / Q000601:surgery; D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D005934:Glucagon / Q000097:blood; D006801:Humans; D007003:Hypoglycemia / Q000209:etiology*; D066298:In Vitro Techniques; D007328:Insulin / Q000097:blood / Q000378:metabolism*; D000078790:Insulin Secretion; D008279:Magnetic Resonance Imaging; D010190:Pancreatic Neoplasms / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology / Q000601:surgery; D013004:Somatostatin / Q000097:blood / Q000378:metabolism*
chemical_list: D001786:Blood Glucose; D007328:Insulin; D013004:Somatostatin; D005934:Glucagon