The recent report on “macroprolactin and hyperprolactinaemia” is very interesting. Jamaluddin et al. noted that 4.4 % of the patients have macroprolactin and concluded that “macroprolactin is a significant cause of misdiagnosis, unnecessary investigation, and inappropriate treatment.” Similar to many other “macro” phenomenon (macroCK, macroamylase, etc.), the macroprolactin can result in aberra...

(range, 250% to 86%) indicates a highly variable, sampledependent response of the ACS:180 assay to macroprolactin. The great disparity of values observed when comparing results from macroprolactinemic samples measured by the Elecsys or the Immulite assay with the results obtained by a low-reading method such as ACS:180 may reflect variation in the structure of macroprolactin. Macroprolactin is ...

Autonomous secretion of prolactin (PRL) by a pituitary prolactinoma is a relatively common endocrine disorder characterized by increased serum concentrations of PRL and symptoms of menstrual irregularity, infertility, and galactorrhea in women and impotence and lack of libido in men (1 ). These clinical symptoms are common, and measurement of serum PRL is a key investigation used to identify th...

To the Editor: Vieira et al. (1) used the Wallac Delfia immunofluorometric assay to demonstrate that macroprolactin is a common cause of apparent hyperprolactinemia, and this confirms our experience (2) and that of others (3). However, their data validating the polyethylene glycol (PEG) precipitation as a screening method for detecting macroprolactinemia are substantially different than ours (2...

Sir: Hyperprolactinemia is of particular concern with antipsychotic medication, as symptoms associated with high prolactin levels, e.g., sexual dysfunction, can have a negative impact on the patient’s adherence to treatment, and has significant implications for the short-term and long-term health of patients. In general, second-generation antipsychotics (SGAs) produce lower increases in prolact...

INTRODUCTION Prolactin (PRL) exists in different forms in human serum. The predominant form is monomeric PRL (molecular mass 23 kDa) with smaller amounts of big PRL (molecular mass 50-60 kDa) and at times macroprolactin (molecular mass 150-170 kDa). Macroprolactin, generally considered to be biologically inactive, accounts for the major part of prolactin in some patients. Different immunoassays...

BACKGROUND Macroprolactin (big big prolactin) has reduced bioactivity and is measured by immunoassays for prolactin when it accumulates in the plasma of some individuals. We applied normative data for serum prolactin after treatment of sera to remove macroprolactin to elucidate the contribution of macroprolactin to misleading diagnoses, inappropriate investigations, and unnecessary treatment. ...

Human prolactin (PRL) is synthesized as a prehormone with a molecular weight of 26,000 kDa. When the preprolactin is cleaved, the resulting polypeptide has a molecular weight of 23,000 kDa, and this monomeric form accounts for the majority of total PRL. Serum also contains a 50,000-kDa form that is termed big PRL and another species with a molecular weight of greater than l00,000 kDa, which is ...

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 lit...

BACGROUND To assess the contribution of macroprolactin to high serum prolactin levels and their association with thyroid status and thyroid autoimmunity during pregnancy. METHODS 138 pregnant women who suspected of having thyroid dysfunction were studied and divided into three groups according to the thyroid status; group 1; euthyroidism (n 40), group 2; hypothyroidism (n 54), and group 3; hy...