title: Pituitary magnetic resonance imaging and function in patients with growth hormone deficiency with and without mutations in GHRH-R, GH-1, or PROP-1 genes.
abstract: Pituitary stalk interruption and ectopic posterior lobe on magnetic resonance imaging (MRI) are frequently observed in patients with GH deficiency (GHD), but their pathogenesis remains controversial. We performed pituitary stimulation tests, MRI, and studied GH-1, GHRH receptor (GHRH-R), and Prophet of Pit-1 (PROP-1) genes in 76 patients with GHD. Of 33 patients with isolated GHD, 4 had GH-1 deletions and 4 had GHRH-R mutations; of 43 patients with combined pituitary hormone deficiency, 1 had PIT-1 and 5 had PROP-1 mutations. Compared with the 62 patients without mutations, 14 patients with mutations had higher frequency of consanguinity (57 vs. 2%, P < 0.001), familial cases (21 vs. 3%, P < 0.05), and lower frequency of breech delivery or hypoxemia at birth (0 vs. 39%, P < 0.005). On MRI, all patients with mutations had an intact stalk, whereas it was interrupted or thin in 74% without mutations (P < 0.001). The posterior pituitary lobe was in normal position in 92% of patients with mutations against 13% without mutations (P < 0.001). Among patients with combined pituitary hormone deficiency, hormonal deficiencies were of pituitary origin in all with PROP-1 and PIT-1 mutations and suggestive of hypothalamic origin in 81% without mutations. Perinatal insults were associated with thin/interrupted pituitary stalk, ectopic posterior lobe, and hypothalamic origin of hormonal deficiencies. In contrast, GH-1, GHRH-R, and PROP-1 mutations were associated with consanguineous parents, intact pituitary stalk, normal posterior lobe, and pituitary origin of hormonal deficiencies. We conclude that pituitary MRI and hormonal response to stimulation tests are useful in selection of patients and candidate genes to elucidate the etiological diagnosis of GHD.
authors.affiliation: Unidade de Endocrinologia do Desenvolvimento, Laboratório de Hormônios e Genética Molecular, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, Av. Eneas de Carvalho Aguiar 155, PAMB 2 Andar Bloco 6, 01065-970 São Paulo, Brazil.
authors.forename: Maria Geralda F
authors.initials: MG
authors.lastname: Osorio
authors.forename: Suemi
authors.initials: S
authors.lastname: Marui
authors.forename: Alexander A L
authors.initials: AA
authors.lastname: Jorge
authors.forename: Ana C
authors.initials: AC
authors.lastname: Latronico
authors.forename: Leonard S S
authors.initials: LS
authors.lastname: Lo
authors.forename: Claudia C
authors.initials: CC
authors.lastname: Leite
authors.forename: Vivian
authors.initials: V
authors.lastname: Estefan
authors.forename: Berenice B
authors.initials: BB
authors.lastname: Mendonca
authors.forename: Ivo J P
authors.initials: IJ
authors.lastname: Arnhold
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D003241:Consanguinity; D005260:Female; D017353:Gene Deletion; D018398:Homeodomain Proteins / Q000235:genetics*; D019382:Human Growth Hormone / Q000172:deficiency* / Q000235:genetics*; D006801:Humans; D007031:Hypothalamus / Q000503:physiopathology; D007223:Infant; D008279:Magnetic Resonance Imaging; D008297:Male; D009154:Mutation; D010902:Pituitary Gland / Q000473:pathology* / Q000503:physiopathology; D010904:Pituitary Gland, Posterior / Q000473:pathology; D018013:Receptors, Neuropeptide / Q000235:genetics*; D018017:Receptors, Pituitary Hormone-Regulating Hormone / Q000235:genetics*
chemical_list: D018398:Homeodomain Proteins; C102134:Prophet of Pit-1 protein; D018013:Receptors, Neuropeptide; D018017:Receptors, Pituitary Hormone-Regulating Hormone; D019382:Human Growth Hormone; C048250:somatotropin releasing hormone receptor