Journal of Reproduction & Infertility

Journal of Reproduction & Infertility

Macroprolactin; A Frequent Cause of Misdiagnosed Hyperprolactinemia in Clinical Practice

Authors
1 Guru Nanak Eye Center, New Delhi, New Delhi, India
2 Department of Neurosurgery, G.B. Pant Hospital, New Delhi, India
3 Department of Biochemistry, Lady Hardinge Medical College and S.S.K. Hospital, New Delhi, India
Abstract
Introduction: Macroprolactin is a significant cause of misdiagnosis, unnecessary investigation, and inappropriate treatment in patients with hyperprolactinemia. Its frequency has not been clearly established due to technical difficulties in identifying it. Most laboratories and clinicians are unaware of macroprolactin interferences in prolactin assays. Materials and Methods: A comprehensive literature search was conducted on the websites of the National Library of Medicine (http://www.ncbl.nlm.nih.gov) and PubMed Central, the US National Library of Medicine’s digital archive of life sciences literature (http://www.pubmedcentral.nih.gov/). The data were also looked for in relevant books and journal. Results: Macroprolactin is a non-bioactive prolactin isoform usually composed of a prolactin monomer and an IgG molecule having a prolonged clearance rate similar to that of immunoglobulins. This isoform is clinically non-reactive but it interferes with immunological assays used for the detection of prolactin. Conclusion: There is a need to understand and explore the recent progress in the diagnosis and pathophysiology of macroprolactinemia for improving patient care.
Keywords

  1. Suh HK, Frantz AG. Size heterogeneity of human prolactin in plasma and pituitary extracts. J Clin Endocrinol Metab. 1974;39(5):928-35.
  2. Rogol AD, Rosen SW. Prolactin of apparent large molecular size: the major immunoactive prolactin component in plasma of a patient with a pituitary tumor. J Clin Endocrinol Metab. 1974;38(4):714-7.
  3. Whittaker PG, Wilcox T, Lind T. Maintained fertileity in a patient with hyperprolactinemia due to big, big prolactin. J Clin Endocrinol Metab. 1981;53(4): 863-6.
  4. Andersen AN, Pedersen H, Djursing H, Andersen BN, Friesen HG. Bioactivity of prolactin in a woman with an excess of large molecular size prolactin, persistent hyperprolactinemia and spontaneous conception. Fertil Steril. 1982;38(5):625-8.
  5. Jackson RD, Wortsman J, Malarkey WB. Macroprolactinemia presenting like a pituitary tumor. Am J Med. 1985;78(2):346-50.
  6. Sluijmer AV, Lappöhn RE. Clinical history and outcome of 59 patients with idiopathic hyperprolactinemia. Fertil Steril. 1992;58(1):72-7.
  7. Hattori N, Ishihara T, Ikekubo K, Moridera K, Hino M, Kurahachi H. Autoantibody to human prolactin in patients with idiopathic hyperprolactinemia. J Clin Endocrinol Metab. 1992;75(5):1226-9.
  8. Leite V, Cosby H, Sobrinho LG, Fresnoza MA, Santos MA, Friesen HG. Characterization of big, big prolactin in patients with hyperprolactinaemia. Clin Endocrinol (Oxf). 1992;37(4):365-72.
  9. Bonhoff A, Vuille JC, Gomez F, Gellersen B. Identification of macroprolactin in a patient with asymptomatic hyperprolactinemia as a stable PRL-IgG complex. Exp Clin Endocrinol Diabetes. 1995; 103(4):252-5.
  10. Hattori N, Ikekubo K, Ishihara T, Moridera K, Hino M, Kurahachi H. Correlation of the antibody titers with serum prolactin levels and their clinical course in patients with anti-prolactin autoantibody. Eur J Endocrinol. 1994;130(5):438-45.
  11. Cavaco B, Prazeres S, Santos MA, Sobrinho LG, Leite V. Hyperprolactinemia due to big big prolactin is differently detected by commercially available immunoassays. J Endocrinol Invest. 1999;22(3):203-8.
  12. Jackson RD, Wortsman J, Malarkey WB. Persistence of large molecular weight prolactin secretion during pregnancy in women with macroprolactinemia and its presence in fetal cord blood. J Clin Endocrinol Metab. 1989;68(6):1046-50.
  13. Suliman AM, Smith TP, Gibney J, McKenna TJ. Frequent misdiagnosis and mismanagement of hyperprolactinemic patients before the introduction of macroprolactin screening: application of a new strict laboratory definition of macroprolactinemia. Clin Chem. 2003;49(9):1504-9.
  14. Carotenuto A, D'Ursi AM, Nardi E, Papini AM, Rovero P. Conformational analysis of a glycosylated human myelin oligodendrocyte glycoprotein peptide epitope able to detect antibody response in multiple sclerosis. J Med Chem. 2001;44 (14):2378-81.
  15. Coudevylle N, Rokas D, Sakarellos-Daitsiotis M, Krikorian D, Panou-Pomonis E, Sakarellos C, et al. Phosphorylated and nonphosphorylated epitopes of the La/SSB autoantigen: comparison of their antigenic and conformational characteristics. Biopoly-mers. 2006;84(4):368-82.
  16. Sinha YN. Structural variants of prolactin: occurrence and physiological significance. Endocr Rev. 1995;16(3):354-69.
  17. Hattori N, Ikekubo K, Nakaya Y, Kitagawa K, Inagaki C. Immunoglobulin G subclasses and prolactin (PRL) isoforms in macroprolactinemia due to anti-PRL autoantibodies. J Clin Endocrinol Metab. 2005;90(5):3036-44.
  18. Hattori N, Inagaki C. Anti-prolactin (PRL) auto-antibodies cause asymptomatic hyperprolactinemia: bioassay and clearance studies of PRLimmunoglobulin G complex. J Clin Endocrinol Metab. 1997;82(9):3107-10.
  19. Cavaco B, Leite V, Santos MA, Arranhado E, Sobrinho LG. Some forms of big big prolactin behave as a complex of monomeric prolactin with an immunoglobulin G in patients with macroprolactinemia or prolactinoma. J Clin Endocrinol Metab. 1995;80(8):2342-6.
  20. Kavanagh-Wright L, Smith TP, Gibney J, Mc Kenna TJ. Characterization of macroprolactin and assessment of markers of autoimmunity in macroprolactinaemic patients. Clin Endocrinol (Oxf). 2009;70(4):599-605.
  21. Hattori N, Nakayama Y, Kitagawa K, Li T, Inagaki C. Development of anti-PRL (prolactin) autoantibodies by homologous PRL in rats: a model for macroprolactinemia. Endocrinology. 2007;148(5): 2465-70.
  22. Fahie-Wilson MN, Ellis AR, Seth J. Macroprolactin-a major problem in immunoassays for prolactin. Clin Chem. 1999;45 Suppl:A83.
  23. Hattori N. The frequency of macroprolactinemia in pregnant women and the heterogeneity of its etiologies. J Clin Endocrinol Metab. 1996;81(2): 586-90.
  24. Vallette-Kasic S, Morange-Ramos I, Selim A, Gunz G, Morange S, Enjalbert A, et al. Macropro-lactinemia revisited: a study on 106 patients. J Clin Endocrinol Metab. 2002;87(2):581-8.
  25. Leslie H, Courtney CH, Bell PM, Hadden DR, McCance DR, Ellis PK, et al. Laboratory and clinical experience in 55 patients with macroprolactinemia identified by a simple polyethylene glycol precipitation method. J Clin Endocrinol Metab. 2001;86(6):2743-6.
  26. Olukoga AO, Kane JW. Macroprolactinaemia: validation and application of the polyethylene glycol precipitation test and clinical characterization of the condition. Clin Endocrinol (Oxf). 1999; 51(1):119-26.
  27. Fahie-Wilson MN. Polyethylene glycol precipitation as a screening method for macroprolactinemia. Clin Chem. 1999;45(3):436-7.
  28. Sandoval C, González B, Cheng S, Esquenazi Y, Mercado M. [Macroprolactinemia identification in patients with hyperprolactinemia]. Ginecol Obstet Mex. 2007;75(8):459-64. Spanish.
  29. Dzeranova LK, Goncharov NP, Dobracheva AD, Kolesnikova GS, Giniiatullina EN, Mel'nichenko GA. [The diagnostic value of macroprolactin in hyperprolactinemia]. Klin Lab Diagn. 2007;(10): 16-9. Russian.
  30. Ram S, Harris B, Fernando JJ, Gama R, FahieWilson M. False-positive polyethylene glycol precipitation tests for macroprolactin due to increased serum globulins. Ann Clin Biochem. 2008;45(Pt 3):256-9.
  31. Donadio F, Barbieri A, Angioni R, Mantovani G, Beck-Peccoz P, Spada A, et al. Patients with macroprolactinaemia: clinical and radiological features. Eur J Clin Invest. 2007;37(7):552-7.
  32. Taghavi M, Sedigheh F. Macroprolactinemia in patients presenting with hyperandrogenic symptoms and hyperprolactinemia. Int J Endocrinol Metab. 2008;6(3):140-3.
  33. Taghavi M, Khadjeh Dalouie M. [Evaluating the prevalence of macroprolactinemia and hyperprolactinemia and comparing their clinical and radiological signs in infertile women]. J Reprod Infertil. 2007;8(2):182. Persian.
  34. Hattori N, Nakayama Y, Kitagawa K, Ishihara T, Saiki Y, Inagaki C. Anti-prolactin (PRL) autoantibody-binding sites (epitopes) on PRL molecule in macroprolactinemia. J Endocrinol. 2006;190(2): 287-93.
  35. Ahlquist JA, Fahie Wilson MN. On the origin and distribution of macroprolactin. J Endocrinol. 2000; 164 suppl:P34.
  36. Olukoga AO. Macroprolactinemia is clinically important. J Clin Endocrinol Metab. 2002;87(10): 4833-4.
  37. Alfonso A, Rieniets KI, Vigersky RA. Incidence and clinical significance of elevated macroprolactin levels in patients with hyperprolactinemia. Endocr Pract. 2006;12(3):275-80.