title: Total and free insulin-like growth factor I, insulin-like growth factor binding protein 3 and acid-labile subunit reflect clinical activity in acromegaly.
abstract: The aim was to evaluate, markers of disease activity in acromegaly in relation to perceived disease activity. Thirty-seven consecutively treated, acromegalic patients, classified by clinical symptoms as inactive (n=16), slightly active (n=10) and active (n=11), entered the study. When evaluating the inactive and the active groups, we found that positive and negative predictive values (PV(pos), PV(neg)) for clinical disease activity of total and free insulin-like growth factor-I (IGF-I) were 0.59, 0.90 and 1.00, 0.82 respectively. Acid-labile subunit (ALS) showed diagnostic merit similar to insulin-like growth factor binding protein-3 (IGFBP-3) with PV(pos) of 0.69 and 0.71 and PV(neg) of 0.91 and 0.92 respectively. We conclude that free IGF-I is more closely related than total IGF-I to perceived disease activity and is as such useful when evaluating previously treated acromegaly for disease activity. Total IGF-I, IGFBP-3 and ALS possess a higher PV(neg) for the clinical disease activity. None of the parameters can at present be claimed to be superior to the others and thus all the measured parameters are recommended to be part of the evaluation of acromegalic patients.
authors.affiliation: Department of Endocrinology, Rigshospitalet, Denmark
authors.forename: S B
authors.initials: SB
authors.lastname: Sneppen
authors.forename: M
authors.initials: M
authors.lastname: Lange
authors.forename: L M
authors.initials: LM
authors.lastname: Pedersen
authors.forename: L Ø
authors.initials: LØ
authors.lastname: Kristensen L
authors.forename: K M
authors.initials: KM
authors.lastname: Main
authors.forename: A
authors.initials: A
authors.lastname: Juul
authors.forename: N E
authors.initials: NE
authors.lastname: Skakkebaek
authors.forename: U
authors.initials: U
authors.lastname: Feldt-Rasmussen
mesh_terms: D000172:Acromegaly / Q000097:blood* / Q000175:diagnosis / Q000473:pathology / Q000503:physiopathology; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D002352:Carrier Proteins / Q000097:blood*; D005260:Female; D006023:Glycoproteins / Q000097:blood*; D006801:Humans; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000097:blood*; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D008297:Male; D008875:Middle Aged
chemical_list: D015415:Biomarkers; D002352:Carrier Proteins; D006023:Glycoproteins; D018972:Insulin-Like Growth Factor Binding Protein 3; C075944:insulin-like growth factor binding protein, acid labile subunit; D007334:Insulin-Like Growth Factor I