Strachan Mark W J, Teoh Wei Leng, Don-Wauchope Andrew C, Seth John, Stoddart Mary, Beckett Geoffrey J
Metabolic Unit, Western General Hospital, Edinburgh and Department of Clinical Biochemistry, Royal Infirmary of Edinburgh, Edinburgh, UK.
Clin Endocrinol (Oxf). 2003 Sep;59(3):339-46. doi: 10.1046/j.1365-2265.2003.01852.x.
Macroprolactin is a complex of prolactin (PRL) and IgG and may account for a significant proportion of cases of 'idiopathic hyperprolactinaemia'. In this study, we sought to determine the prevalence and clinical features of macroprolactinaemia in patients diagnosed with hyperprolactinaemia in our region, with a view to determining how patients with macroprolactinaemia should be investigated and managed.
An Immuno-1 automated immunoassay system with polyethylene glycol (PEG) precipitation was used to identify macroprolactin, with a recovery of </= 50% taken as indicating significant macroprolactinaemia. Macroprolactin was found in 58 (21%) of 273 patients with a total PRL > 700 mU/l. The clinical records of 51 (44 female) were available for retrospective review.
The mean (range) age of patients was 39.5 (18-82) years. The median (range) concentrations for the various forms of PRL were: total PRL 1130 mU/l (728-5116), monomeric PRL 240 mU/l (50-656) and macroprolactin 895 mU/l (381-4854). Classical symptoms of hyperprolactinaemia were present in 39% of patients, although in many there were other possible explanations for their symptomatology. Pituitary adenomas were identified in six out of 36 people who underwent neuroimaging. Five of these patients had a microadenoma and one had a 10-mm macroadenoma (although, in this patient macroprolactin was identified after the discovery of the tumour). There was no relationship between macroprolactin concentrations and the presence of hyperprolactinaemic symptoms or neuroimaging abnormalities.
Macroprolactinaemia is a common occurrence in patients with hyperprolactinaemia, but associated symptomatology may not necessarily be linked. The neuroimaging abnormalities were also probably incidental findings and it is questionable whether neuroimaging is necessary when significant macroprolactinaemia is identified and the concentration of monomeric PRL is not elevated (using the Immuno-1 assay system, following PEG precipitation).
大分子催乳素是催乳素（PRL）与IgG的复合物，可能在“特发性高催乳素血症”病例中占相当比例。在本研究中，我们试图确定本地区诊断为高催乳素血症患者中大分子催乳素血症的患病率和临床特征，以确定对大分子催乳素血症患者应如何进行检查和处理。
使用配备聚乙二醇（PEG）沉淀的Immuno-1自动免疫分析系统鉴定大分子催乳素，回收率≤50%被视为存在显著大分子催乳素血症。在273例总PRL>700 mU/l的患者中，有58例（21%）检测到大分子催乳素。51例（44例女性）患者的临床记录可供回顾性分析。
患者的平均（范围）年龄为39.5（18 - 82）岁。各种形式PRL的中位数（范围）浓度分别为：总PRL 1130 mU/l（728 - 5116）、单体PRL 240 mU/l（50 - 656）和大分子催乳素895 mU/l（381 - 4854）。39%的患者出现高催乳素血症的典型症状，不过在许多患者中，其症状可能还有其他原因。在接受神经影像学检查的36人中，有6人发现垂体腺瘤。其中5例患者为微腺瘤，1例为10 mm的大腺瘤（不过，该患者在肿瘤发现后才检测到大分子催乳素）。大分子催乳素浓度与高催乳素血症症状或神经影像学异常的存在之间无关联。
大分子催乳素血症在高催乳素血症患者中很常见，但相关症状不一定与之相关。神经影像学异常可能也是偶然发现，当确定存在显著大分子催乳素血症且单体PRL浓度未升高时（使用Immuno-1分析系统，PEG沉淀后），神经影像学检查是否必要值得怀疑。
