title: Electrical short-circuit in β-cells from a patient with non-insulinoma pancreatogenous hypoglycemic syndrome (NIPHS): a case report.
abstract: BACKGROUND
  Non-insulinoma pancreatogenous hypoglycemic syndrome is a rare disorder among adults, and, to our knowledge, only about 40 cases have been reported in the literature.
  
  
  METHODS
  The patient is a previously healthy 35-year-old Caucasian man. His symptoms began four years ago when he suddenly felt weakness in his legs and started sweating for unknown reasons. The symptoms worsened, and laboratory tests revealed hypoglycemia and hyperinsulinemia at the time of the symptoms. All diagnostics attempts using magnetic resonance imaging, computed tomography, and endoscopic ultrasound did not reveal any abnormalities. At this stage, surgical intervention was planned, and a distal 80% pancreatectomy was performed. The histopathologic and immunohistochemical investigations of the pancreas showed an increased number of islets of different sizes, more or less evenly distributed in the gland, but no insulinoma. Patch-clamp recordings from isolated pancreatic β-cells showed that, even at a low glucose concentration (3 mmol/L), the β-cell membrane was depolarized, and action potentials were seen. Surprisingly, in patch-clamp experiments, the addition of diazoxide had a marked effect on K-ATP channel activity and membrane potential, but no effect on insulin levels in vivo before surgery.
  
  
  CONCLUSIONS
  This case report adds new information on the pathogenesis of non-insulinoma pancreatogenous hypoglycemic syndrome, as we performed an electrophysiologic characterization of isolated islet cells. We show, for the first time, that β-cells isolated from a non-insulinoma pancreatogenous hypoglycemic syndrome patient are constantly depolarized, even at low glucose levels, but display normal K-ATP channel physiology.
authors.affiliation: The Rolf Luft Research Center for Diabetes and Endocrinology, Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden. robert.branstrom@ki.se.
authors.forename: Robert
authors.initials: R
authors.lastname: Bränström
authors.forename: Erik
authors.initials: E
authors.lastname: Berglund
authors.forename: Pontus
authors.initials: P
authors.lastname: Curman
authors.forename: Lars
authors.initials: L
authors.lastname: Forsberg
authors.forename: Anders
authors.initials: A
authors.lastname: Höög
authors.forename: Lars
authors.initials: L
authors.lastname: Grimelius
authors.forename: Per-Olof
authors.initials: PO
authors.lastname: Berggren
authors.forename: Per
authors.initials: P
authors.lastname: Mattsson
authors.forename: Per
authors.initials: P
authors.lastname: Hellman
authors.forename: Lisa
authors.initials: L
authors.lastname: Juntti-Berggren