Kato S, Tachikawa T, Ozawa K, Konno M, Okuda M, Fujisawa T, Nakazato Y, Tajiri H, Iinuma K
Department of Pediatrics, Tohoku University School of Medicine, Sendai, Japan.
Pediatrics. 2001 Jun;107(6):E87. doi: 10.1542/peds.107.6.e87.
Serology and (13)C-urea breath test have been widely used as noninvasive tests to detect Helicobacter pylori infection. However, easier collection of samples and lower costs are desirable for diagnosis of the individual patient or for use in epidemiologic studies. Our aim was to study the diagnostic accuracy of a recently developed urine-based enzyme-linked immunosorbent assay (ELISA) kit for the detection of H pylori-specific immunoglobulin G (IgG) antibodies in children.
Specimens of serum and randomly voided urine were collected from 816 children (0-15 years old) and were analyzed using 2 serum-based ELISA kits and a urine-based ELISA kit, respectively. Based on results of serology, the sensitivity, specificity, and accuracy of the urine-based ELISA kit were evaluated. With regard to false-positive and false-negative results, urinary IgG concentrations and IgG/creatinine levels were studied.
Both serum-based ELISAs were positive in 41 children and were negative in 666, who were enrolled in this study. The remaining 109 children were excluded because of disagreement between the results of the 2 serum-based ELISAs, including indeterminate values. Overall sensitivity, specificity, and accuracy of urine-based ELISA test compared with serology were 85.4%, 95.5%, and 94.9%, respectively. On positivity rates, the urine-based ELISA was closely coincident with the serum-based ELISA in each age group. There was no correlation between antibody levels detected by urine-based ELISA and each serum-based ELISA. Urinary IgG concentrations and IgG/creatinine levels were significantly higher in false-positives and were lower in false-negatives than in true-positives plus true-negatives for serology. Most of those with false-positive results had trace to moderate proteinuria.
The urine-based ELISA is an alternative to serum-based ELISA for diagnosis of H pylori infection in children and should be suitable for large-scale epidemiologic studies concerning the organism. In children with proteinuria, results of the test should be interpreted with caution. It is possible that the urine-based ELISA method would be applicable to diagnosis of other infectious diseases.
血清学检测和碳-13尿素呼气试验已被广泛用作检测幽门螺杆菌感染的非侵入性检测方法。然而，对于个体患者的诊断或流行病学研究而言，更简便的样本采集方法和更低的成本是可取的。我们的目的是研究一种新开发的基于尿液的酶联免疫吸附测定（ELISA）试剂盒检测儿童幽门螺杆菌特异性免疫球蛋白G（IgG）抗体的诊断准确性。
收集了816名0至15岁儿童的血清样本和随机尿液样本，分别使用两种基于血清的ELISA试剂盒和一种基于尿液的ELISA试剂盒进行分析。根据血清学检测结果，评估基于尿液的ELISA试剂盒的敏感性、特异性和准确性。针对假阳性和假阴性结果，研究了尿IgG浓度和IgG/肌酐水平。
在本研究纳入的儿童中，两种基于血清的ELISA检测结果均为阳性的有41名，阴性的有666名。其余109名儿童因两种基于血清的ELISA检测结果不一致（包括不确定值）而被排除。与血清学检测相比，基于尿液的ELISA检测的总体敏感性、特异性和准确性分别为85.4%、95.5%和94.9%。在阳性率方面，基于尿液的ELISA在各年龄组与基于血清的ELISA密切一致。基于尿液的ELISA检测到的抗体水平与每种基于血清的ELISA检测结果之间无相关性。血清学检测中，假阳性组的尿IgG浓度和IgG/肌酐水平显著高于真阳性加真阴性组，假阴性组则低于真阳性加真阴性组。大多数假阳性结果的儿童有微量至中度蛋白尿。
基于尿液的ELISA可作为儿童幽门螺杆菌感染诊断中基于血清的ELISA的替代方法，应适用于有关该病原体的大规模流行病学研究。对于有蛋白尿的儿童，该检测结果的解释应谨慎。基于尿液的ELISA方法有可能适用于其他传染病的诊断。
