催乳素免疫测定法和钩状效应

Prolactin immunometric assays and hook effect

血清催乳素（PRL）免疫测定法存在高剂量钩状效应，主要是由于较高浓度的抗原饱和抗体，阻止抗体-抗原-抗体夹心复合物的形成，产生假性低值。临床上已报道许多侵袭性巨催乳素瘤的病例因PRL钩状效应而被误诊，中年男性多见，稀释前PRL水平呈轻、中度升高，主要表现为垂体占位效应，手术或放射治疗效果不佳。多巴胺受体激动剂能使PRL水平下降，使肿瘤缩小。可通过血清稀释后测定PRL或采用其他不存在钩状效应的测定方法等避免假性低值和错误治疗。

Serum prolactin （PRL） immunometric assays have the pitfall of high dose hook effect. A very high concentration of antigen saturates the antibodies and prevents the formation of the ＂sandwich complexes＂ ,which results in falsely low values. Many cases of invasive macroprolactinoma have been misdiagnosed because of PRL hook effect. Most patients were middle age men,with moderately elevated PRL levels before dilution and pituitary compression effect. Surgical procedures or irradiation have no effect, but dopamine agonists can normalize serum prolactin levels and reduce tumor size in most patients. Measurements of PRL in diluted serum samples or using an assay with a proven lack of hook effect may avoid falsely low estimation and management errors.