title: Lasting 18F-DOPA PET uptake after clinical remission of the focal form of congenital hyperinsulinism.
abstract: BACKGROUND
  Positron emission tomography (PET) using (18)F-DOPA is a useful tool for detecting the focal forms of congenital hyperinsulinism. (18)F-DOPA is taken up by aromatic L-amino acid decarboxylase in pancreatic β-cells. However, the role of this enzyme in insulin secretion is unknown.
  
  
  METHODS
  A Japanese boy who presented with symptomatic hyperinsulinemic hypoglycemia at the age of 2 days and spontaneous resolution at 1 year and 10 months was subjected to mutational analysis and repeated (18)F-DOPA PET scans.
  
  
  RESULTS
  Mutational analysis revealed a paternally inherited monoallelic mutation, c.4186G>T (p.D1396Y), in the ABCC8 gene, and an (18)F-DOPA PET scan revealed focal uptake in the body of the pancreas. The patient was successfully treated with frequent feeding. A follow-up PET scan revealed virtually identical uptake to that observed previously. However, in the arterial stimulation-venous sampling procedure, no significant insulin release was observed. He was placed on a normal diet, and no hypoglycemia recurrence was observed.
  
  
  CONCLUSIONS
  This case demonstrates two important findings. Firstly, the uptake of (18)F-DOPA does not correlate with the insulin-secreting capacity of the lesion. Secondly, clinical remission could be a functional process not necessarily accompanied by the apoptotic death of abnormal β-cells.
authors.affiliation: Department of Pediatric Endocrinology and Metabolism, Children's Medical Center, Osaka City General Hospital, Osaka, Japan.
authors.forename: Tohru
authors.initials: T
authors.lastname: Yorifuji
authors.forename: Yuki
authors.initials: Y
authors.lastname: Hosokawa
authors.forename: Rika
authors.initials: R
authors.lastname: Fujimaru
authors.forename: Rie
authors.initials: R
authors.lastname: Kawakita
authors.forename: Hiraku
authors.initials: H
authors.lastname: Doi
authors.forename: Takako
authors.initials: T
authors.lastname: Matsumoto
authors.forename: Hironori
authors.initials: H
authors.lastname: Nishibori
authors.forename: Michiya
authors.initials: M
authors.lastname: Masue
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000235:genetics; D044903:Congenital Hyperinsulinism / Q000175:diagnosis*; D004295:Dihydroxyphenylalanine / Q000031:analogs & derivatives*; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D050417:Insulin-Secreting Cells / Q000378:metabolism; D008297:Male; D010179:Pancreas / Q000378:metabolism; D049268:Positron-Emission Tomography / Q000379:methods; D024661:Potassium Channels, Inwardly Rectifying / Q000235:genetics; D011955:Receptors, Drug / Q000235:genetics; D064233:Sulfonylurea Receptors
chemical_list: D018528:ATP-Binding Cassette Transporters; D024661:Potassium Channels, Inwardly Rectifying; D011955:Receptors, Drug; D064233:Sulfonylurea Receptors; C043437:fluorodopa F 18; D004295:Dihydroxyphenylalanine