Leonardi G P, Seitz M, Edstrom R, Cruz J, Costello P, Szabo K
Department of Pathology, Nassau County Medical Center, East Meadow, New York 11554.
J Clin Microbiol. 1992 Nov;30(11):2793-6. doi: 10.1128/jcm.30.11.2793-2796.1992.
The performances of three commercially available immunoassays (Chlamydiazyme/Antibody Blocking Assay [Abbott Diagnostics, Abbott Park, Ill.], IDEIA [Analytab Products, Plainview, N.Y.], and Microtrak EIA [Syva Co. Palo Alto, Calif.]) were evaluated for the detection of Chlamydia trachomatis in urine specimens from asymptomatic males. Assay results were compared with direct specimen immunofluorescence (DFA) analysis of urine sediment (Syva Microtrak; Syva Co.), which was chosen as the study confirmation assay. An overall Chlamydia prevalence of 7% (24 of 340) was found in our study population, with peak incidences occurring in the adolescent (8 of 93 specimens) and young adult (11 of 146 specimens) age groups. Sensitivity and specificity data among the Chlamydiazyme, IDEIA, and Microtrak enzyme immunoassays (EIAs) were determined to be 79.1 and 99%, 91.7 and 98%, and 95.8 and 99%, respectively. The Microtrak EIA and IDEIA products demonstrated sensitivities and specificities equal to or greater than those claimed for urine specimens. The diagnostic accuracies of these assays on asymptomatic subjects, along with the ease of this collection method, suggest a role for these products as screening tools. The sensitivity of the Chlamydiazyme assay was lower than that claimed previously in symptomatic patients, with 5 of 24 positive specimens demonstrating false-negative results. In those cases, centrifugation of the original immunoassay aliquot material and then DFA examination confirmed specimen positivity. Urine immunoassay screening in combination with DFA confirmation (which was chosen because it has antibody epitopic specificity different from that of the primary assay) provides a high degree of diagnostic precision. The use of noninvasive collection methods could result in greater testing compliance among asymptomatic males and, subsequently, could reduce the incidences of both symptomatic and silent chlamydial infections.
对三种市售免疫测定法（衣原体酶/抗体阻断测定法[雅培诊断公司，伊利诺伊州雅培公园]、IDEIA[分析实验室产品公司，纽约州普莱恩维尤]和微捕酶免疫测定法[赛瓦公司，加利福尼亚州帕洛阿尔托]）检测无症状男性尿液标本中沙眼衣原体的性能进行了评估。将测定结果与尿液沉淀物的直接标本免疫荧光（DFA）分析（赛瓦微捕；赛瓦公司）进行比较，后者被选作研究确认测定法。在我们的研究人群中，衣原体总体患病率为7%（340例中的24例），发病率高峰出现在青少年（93例标本中的8例）和青年成人（146例标本中的11例）年龄组。衣原体酶法、IDEIA法和微捕酶免疫测定法（EIA）的敏感性和特异性数据分别确定为79.1%和99%、91.7%和98%、95.8%和99%。微捕EIA和IDEIA产品显示出的敏感性和特异性等于或高于针对尿液标本所宣称的水平。这些测定法对无症状受试者的诊断准确性，以及这种采集方法的简便性，表明这些产品可作为筛查工具发挥作用。衣原体酶测定法的敏感性低于先前对有症状患者所宣称的水平，24例阳性标本中有5例显示假阴性结果。在这些病例中，对原始免疫测定等分试样材料进行离心，然后进行DFA检查证实了标本阳性。尿液免疫测定筛查结合DFA确认（之所以选择DFA是因为其抗体表位特异性与主要测定法不同）提供了高度的诊断精确度。使用非侵入性采集方法可能会使无症状男性的检测依从性更高，随后可降低有症状和无症状衣原体感染的发病率。
