title: Pituitary magnetic resonance imaging in 15 patients with Prop1 gene mutations: pituitary enlargement may originate from the intermediate lobe.
abstract: Pituitary morphology in patients with Prop1 gene mutations varies. Most patients demonstrate a normal or small pituitary gland. Occasionally, pituitary enlargement of undetermined origin has also been detected. In the present study we use long-term magnetic resonance imaging findings to characterize the morphological abnormalities of the pituitary gland in 15 patients (aged 2.5-45 yr) with combined pituitary hormone deficiency caused by Prop1 gene mutations (GA296del/GA296del in seven, GA296del/A150del in two, A150del/A150del in five, and GA296del/R73H in one patient) and attempt to uncover the origin and nature of the pituitary enlargement. Small pituitary gland was detected in seven patients (25.2 +/- 14.4 yr of age), normal pituitary size in three patients (10.2 +/- 5.8 yr of age), and pituitary enlargement in five patients (6.5 +/- 2.7 yr of age). The pituitary enlargement consisted of a nonenhancing mass lesion interposed between the normally enhancing anterior lobe and the neurohypophysis. The pituitary stalk was displaced anteriorly, whereas the neurohypophysis was orthotopic, displaying a normal signal. Spontaneous regression of the mass lesion with normalization of the pituitary stalk position was observed in three patients. Our data indicate that although a small pituitary gland is usually observed in older subjects, a significant number of young patients with Prop1 gene mutations demonstrate pituitary enlargement with subsequent regression. The distinct magnetic resonance imaging characteristics of the pituitary enlargement in our patients in conjunction with pertinent data from Prop1-deficient mice suggest that the mass causing the pituitary enlargement most likely originates from the intermediate lobe.
authors.affiliation: First Pediatric Department, Athens University School of Medicine, Aghia Sophia Children's Hospital, Athens, Greece 11527.
authors.forename: Antonis
authors.initials: A
authors.lastname: Voutetakis
authors.forename: Maria
authors.initials: M
authors.lastname: Argyropoulou
authors.forename: Amalia
authors.initials: A
authors.lastname: Sertedaki
authors.forename: Sarantis
authors.initials: S
authors.lastname: Livadas
authors.forename: Paraskevi
authors.initials: P
authors.lastname: Xekouki
authors.forename: Maria
authors.initials: M
authors.lastname: Maniati-Christidi
authors.forename: Ioannis
authors.initials: I
authors.lastname: Bossis
authors.forename: Nicolas
authors.initials: N
authors.lastname: Thalassinos
authors.forename: Nicholas
authors.initials: N
authors.lastname: Patronas
authors.forename: Catherine
authors.initials: C
authors.lastname: Dacou-Voutetakis
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D005260:Female; D015894:Genome, Human; D018398:Homeodomain Proteins / Q000235:genetics*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008661:Metabolism, Inborn Errors / Q000175:diagnosis / Q000235:genetics; D009154:Mutation; D010902:Pituitary Gland / Q000473:pathology*; D010907:Pituitary Hormones / Q000097:blood / Q000172:deficiency*
chemical_list: D018398:Homeodomain Proteins; D010907:Pituitary Hormones; C102134:Prophet of Pit-1 protein