title: Macroprolactinemia in patients with prolactinomas: prevalence and clinical significance.
abstract: BACKGROUND
  Data on the prevalence of macroprolactinemia in patients with prolactinomas is quite limited as the presence of high-molecular prolactin forms is suspected mainly in subjects with mild hyperprolactinemia and negative pituitary imaging.
  
  
  OBJECTIVE
  The main objective of this observational case-control study was to assess the prevalence and clinical significance of macroprolactinemia among patients with prolactinomas.
  
  
  METHODS
  The study population consisted of 239 subjects: 131 prolactinoma patients and 108 sex-, age- and ethnicity- matched healthy controls. Macroprolactinemia was defined by a PRL recovery after PEG precipitation of<40%.
  
  
  RESULTS
  The prevalence of macroprolactinemia among newly diagnosed prolactinoma patients did not differ statistically from the prevalence in the control group (3.5 vs. 3.7%; p=1.000) but was lower although non-significantly than the subgroup of patients treated with dopamine agonists (DA) (3.5 vs.10.8%; p=0.072). Significant association between disruptions of ovarian function and serum levels of the monomeric as well as high-molecular prolactin isoform was found.
  
  
  CONCLUSIONS
  In few cases, the presence of typical hyperprolactinemia-related clinical symptoms and their disappearance after treatment with DA suggests biological activity of macroprolactin comparable with that of monomeric prolactin isoform. Decrease of macroprolactin levels after DA treatment could suggest tumoral origin of the high-molecular isoform in these rare cases. Although macroprolactinemia is considered a benign condition, pituitary imaging, DA treatment, and prolonged follow-up may be necessary in certain cases. An individualized approach to the management of patients with macroprolactinemia should be applied.
authors.affiliation: Clinical Centre of Endocrinology and Gerontology, Medical University, Sofia. atanaskae@yahoo.com
authors.forename: A
authors.initials: A
authors.lastname: Elenkova
authors.forename: N
authors.initials: N
authors.lastname: Genov
authors.forename: Z
authors.initials: Z
authors.lastname: Abadzhieva
authors.forename: G
authors.initials: G
authors.lastname: Kirilov
authors.forename: V
authors.initials: V
authors.lastname: Vasilev
authors.forename: K
authors.initials: K
authors.lastname: Kalinov
authors.forename: S
authors.initials: S
authors.lastname: Zacharieva
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D018491:Dopamine Agonists / Q000627:therapeutic use; D005260:Female; D006801:Humans; D006966:Hyperprolactinemia / Q000097:blood / Q000188:drug therapy / Q000503:physiopathology; D008279:Magnetic Resonance Imaging; D008297:Male; D010053:Ovary / Q000503:physiopathology; D010911:Pituitary Neoplasms / Q000097:blood* / Q000175:diagnosis / Q000188:drug therapy; D011388:Prolactin / Q000097:blood*; D015175:Prolactinoma / Q000097:blood* / Q000175:diagnosis / Q000188:drug therapy
chemical_list: D018491:Dopamine Agonists; C060678:prolactin, polymeric; D011388:Prolactin