Marchildon P, Balaban D H, Sue M, Charles C, Doobay R, Passaretti N, Peacock J, Marshall B J, Peura D A
Enteric Products, Inc., Stony Brook, New York 11790, USA.
Am J Gastroenterol. 1999 Aug;94(8):2105-8. doi: 10.1111/j.1572-0241.1999.01285.x.
Prior studies have suggested that IgG antibody titers may be useful to confirm successful treatment of Helicobacter pylori (H. pylori) infection. However, the diagnostic value of decreasing IgG titers is limited by the necessity to perform pre and posttreatment tests in parallel which requires stored sera. Our objective was to assess the accuracy of IgG antibody titers using the HM-CAP IgG EIA kit (Enteric Products) in monitoring treatment of H. pylori infection and to compare the relative accuracy of parallel versus serial determinations.
The 14C urea breath test (UBT) was used to confirm H. pylori infection in 83 dyspeptic patients and eradication of the organism at 4 wk and 6 months posttreatment. IgG titers pretherapy and 6 months posttherapy were determined either serially (separate EIA plates) or in parallel (same EIA plate), and the relative percent decline in antibody titer was calculated.
When a decline of > or = 25% at 6 months was used as the cut-off for H. pylori eradication, mean sensitivities of serial and parallel determinations were 87.5% and 86.8%, respectively, and mean specificities of both were 100%. In 68 of 75 patients in whom the organism was eradicated, the mean decrease in IgG titer at 6 months was 41.1% for serial determinations and 41.5% for parallel determinations.
Serial or parallel IgG titers offer equivalent diagnostic accuracy for confirming H. pylori eradication after therapy. A > or = 25% decline in titer 6 months after therapy is a sensitive and specific marker for eradication of the infection. Serial evaluation of IgG titers does not require serum storage, and is a cost-effective and accurate alternative to the UBT or endoscopy-based methods.
既往研究表明，IgG抗体滴度可能有助于确认幽门螺杆菌（H. pylori）感染的治疗是否成功。然而，IgG滴度降低的诊断价值受到限制，因为需要同时进行治疗前和治疗后的检测，这就需要保存血清。我们的目的是评估使用HM-CAP IgG酶免疫分析试剂盒（肠道产品）检测IgG抗体滴度在监测H. pylori感染治疗中的准确性，并比较平行检测和系列检测的相对准确性。
采用14C尿素呼气试验（UBT）对83例消化不良患者进行H. pylori感染确认，并在治疗后4周和6个月时检测该菌的根除情况。治疗前和治疗后6个月的IgG滴度采用系列检测（单独的酶免疫分析板）或平行检测（同一酶免疫分析板）进行测定，并计算抗体滴度的相对下降百分比。
以治疗后6个月抗体滴度下降≥25%作为H. pylori根除的临界值时，系列检测和平行检测的平均灵敏度分别为87.5%和86.8%，两者的平均特异性均为100%。在75例细菌被根除的患者中，有68例患者系列检测的IgG滴度在6个月时平均下降41.1%，平行检测平均下降41.5%。
系列或平行IgG滴度在确认治疗后H. pylori根除方面具有同等的诊断准确性。治疗后6个月滴度下降≥25%是感染根除的敏感且特异的标志物。IgG滴度的系列评估不需要保存血清，是一种经济有效且准确的替代UBT或基于内镜检查方法的检测手段。
