title: Posterior pituitary (PP) evaluation in patients with anterior pituitary defect associated with ectopic PP and septo-optic dysplasia.
abstract: OBJECTIVE
  Controversies exist about posterior pituitary (PP) function in subjects with ectopic PP (EPP) and with cerebral midline defects and/or their co-occurrence. We investigate water and electrolyte disturbances in patients at risk for PP dysfunction.
  
  
  METHODS
  The study was conducted in a single Pediatric Endocrinology Research Unit.
  
  
  METHODS
  Forty-two subjects with childhood-onset GH deficiency were subdivided into five groups: normal magnetic resonance imaging (n=8, group 1); EPP (n=15, group 2); septo-optic dysplasia (SOD) with normal PP (n=4, group 3); EPP and SOD without (n=7, group 4), and with additional midline brain abnormalities (n=8, group 5). At a mean age of 16.0±1.1 years, they underwent a 120 min i.v. infusion with hypertonic 5% saline and evaluation of plasma osmolality (Posm), arginine vasopressin (AVP), thirst score (in groups 1 and 2), and urinary osmolality were performed.
  
  
  RESULTS
  Mean Posm and AVP significantly increased from baseline scores (284.7±4.9 mosm/kg and 0.6±0.2 pmol/l) to 120 min after saline infusion (300.5±8.0 mosm/kg and 10.3±3.3 pmol/l, P<0.0001). Group 5 showed higher mean Posm and lower mean AVP at all time points (P<0.0001). Mean thirst score did not show a significantly different trend between the groups 1 and 2. Urine osmolality was above 750 mosm/kg in all but seven patients after osmotic challenge.
  
  
  CONCLUSIONS
  Patients with midline brain abnormalities and EPP have defective osmoregulated AVP. Patients with EPP and congenital hypopituitarism have normal PP function.
authors.affiliation: Department of Pediatrics Epidemiology and Biostatistics Section, Scientific Directorate Pediatric Neuroradiology, IRCCS G. Gaslini Institute, University of Genova, Largo Gerolamo Gaslini 5, 16147 Genova, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Secco
authors.forename: Anna Elsa Maria
authors.initials: AE
authors.lastname: Allegri
authors.forename: Natascia
authors.initials: N
authors.lastname: di Iorgi
authors.forename: Flavia
authors.initials: F
authors.lastname: Napoli
authors.forename: Annalisa
authors.initials: A
authors.lastname: Calcagno
authors.forename: Enrica
authors.initials: E
authors.lastname: Bertelli
authors.forename: Irene
authors.initials: I
authors.lastname: Olivieri
authors.forename: Giovanna
authors.initials: G
authors.lastname: Pala
authors.forename: Stefano
authors.initials: S
authors.lastname: Parodi
authors.forename: Roberto
authors.initials: R
authors.lastname: Gastaldi
authors.forename: Andrea
authors.initials: A
authors.lastname: Rossi
authors.forename: Mohamad
authors.initials: M
authors.lastname: Maghnie
mesh_terms: D000293:Adolescent; D001127:Arginine Vasopressin / Q000097:blood / Q000172:deficiency; D002828:Choristoma; D005260:Female; D006801:Humans; D007018:Hypopituitarism / Q000151:congenital / Q000503:physiopathology; D007031:Hypothalamus / Q000503:physiopathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D009994:Osmolar Concentration; D010904:Pituitary Gland, Posterior / Q000473:pathology / Q000503:physiopathology; D011446:Prospective Studies; D012462:Saline Solution, Hypertonic; D025962:Septo-Optic Dysplasia / Q000503:physiopathology*; D013894:Thirst; D014883:Water-Electrolyte Imbalance / Q000503:physiopathology
chemical_list: D012462:Saline Solution, Hypertonic; D001127:Arginine Vasopressin