title: Nesidioblastosis in adults: a challenging cause of organic hyperinsulinism.
abstract: BACKGROUND
  Nesidioblastosis in adults has been reintroduced into the differential diagnosis of organic hyperinsulinism by the description of 'noninsulinoma pancreatogenous hypoglycaemia syndrome (NIPHS)'.
  
  
  METHODS
  Pathologic specimens of all adult patients (n = 66) operated on for organic hyperinsulinism were re-examined. Five patients fulfilled the histomorphological criteria of nesidioblastosis. Retrospective review of clinical presentation, results of 72-h fasts, intravenous tolbutamide tolerance tests, pre- and intraoperative localization studies and surgical therapy was performed.
  
  
  RESULTS
  In contrast to NIPHS, fasting tests became positive after 8-14 h. Tolbutamide tests were positive and preoperative imaging showed negative results in all patients. At first operation distal pancreatic resections were performed in three patients, resection of the pancreatic body in one patient and biopsy of the pancreatic tail in one patient. Two of three patients with recurrent disease had to be reoperated. One patient showed a coexistence of nesidioblastosis and multiple small insulinomas and is part of a kindred with autosomal dominantly inherited 'familial islet-cell adenomatosis'.
  
  
  CONCLUSIONS
  Surgical exploration is indicated only after thorough biochemical diagnosis. An aggressive strategy for preoperative localization including selective arterial calcium stimulation testing seems justified. There may be a combination of nesidioblastosis and islet cell tumours. A link between beta-cell hyperplasia and progression to insulinoma based on not yet known genetic causes can be suspected.
authors.affiliation: University of Vienna, Medical School, Vienna, Austria. Klaus.Kaczirek@akh-wien.ac.at
authors.forename: K
authors.initials: K
authors.lastname: Kaczirek
authors.forename: A
authors.initials: A
authors.lastname: Soleiman
authors.forename: M
authors.initials: M
authors.lastname: Schindl
authors.forename: C
authors.initials: C
authors.lastname: Passler
authors.forename: C
authors.initials: C
authors.lastname: Scheuba
authors.forename: G
authors.initials: G
authors.lastname: Prager
authors.forename: K
authors.initials: K
authors.lastname: Kaserer
authors.forename: B
authors.initials: B
authors.lastname: Niederle
mesh_terms: D000328:Adult; D003937:Diagnosis, Differential; D005215:Fasting; D005260:Female; D006801:Humans; D006946:Hyperinsulinism / Q000175:diagnosis* / Q000601:surgery; D007150:Immunohistochemistry; D007340:Insulinoma / Q000175:diagnosis; D008297:Male; D008875:Middle Aged; D009377:Multiple Endocrine Neoplasia / Q000175:diagnosis / Q000601:surgery; D010182:Pancreatic Diseases / Q000175:diagnosis* / Q000601:surgery