title: [Discrepancy between IGF-1 and GH during 75 g oral glucose tolerance test measures to acromegaly screening in a patient with macroprolactinoma--case report and literature review].
abstract: We describe a patient with macroprolactinoma and discrepant insulin-like growth factor (IGF-1) concentration (elevated) and growth hormone (GH) values during a 75 g oral glucose tolerance test (normal), that were measured to evaluate the co-secretion of GH by tumor. With the bromocriptin use, the patient achieved normalization of prolactin, but persisted with high levels of IGF1, suggesting to be subclinical acromegaly. After the development of new more sensitive GH assays, cases of discrepant GH and IGF-1 results have been observed and taken to some authors to suggest that GH nadir concentration during 75 g OGTT used to acromegaly diagnosis and treatment could be lower than values considered currently normal. Thus, if this is confirmed, subclinical and oligosymptomatic acromegaly cases could have earlier diagnoses.
authors.affiliation: Serviço de Endocrinologia, Hospital de Clínicas, Universidade Federal de Uberlândia, MG.
authors.forename: Fabrícia Torres
authors.initials: FT
authors.lastname: Gonçalves
authors.forename: Taciana C Maia
authors.initials: TC
authors.lastname: Feibelmann
authors.forename: Maria Luiza M P
authors.initials: ML
authors.lastname: Fernandes
authors.forename: Alessandra R C
authors.initials: AR
authors.lastname: Fonseca
authors.forename: Henrique Pierotti
authors.initials: HP
authors.lastname: Arantes
authors.forename: Paulo Tannús
authors.initials: PT
authors.lastname: Jorge
mesh_terms: D000172:Acromegaly / Q000097:blood / Q000175:diagnosis*; D001971:Bromocriptine / Q000627:therapeutic use; D005951:Glucose Tolerance Test; D013006:Growth Hormone / Q000097:blood / Q000378:metabolism*; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000032:analysis* / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D010911:Pituitary Neoplasms / Q000097:blood* / Q000188:drug therapy; D015175:Prolactinoma / Q000097:blood* / Q000188:drug therapy
chemical_list: D001971:Bromocriptine; D007334:Insulin-Like Growth Factor I; D013006:Growth Hormone