Modified two-tier testing (MTTT) for Lyme borreliosis (i.e. confirmation with an EIA instead of an immunoblot) has been shown to have improved sensitivity compared with standard two-tier testing (STTT) in samples from American patients, without losing specificity. The current study assesses the sensitivity and specificity of various algorithms of MTTT in European patients with erythema migrans (EM) as a model disease for early Lyme borreliosis, and in appropriate controls. Four different immunoassays were used in the first tier, followed by either an immunoblot or the C6-EIA, or were used as standalone single-tier test. These tests were performed on consecutively collected sera of 228 Dutch patients with physician-diagnosed EM in the setting of general practice, 231 controls from the general population, and 50 controls with potentially cross-reactive antibodies. All the variants of MTTT that were studied had significantly higher sensitivity compared with their equivalent STTT, while retaining comparable specificity. Within the MTTT algorithms, classifying equivocal results as positive yielded better diagnostic parameters than classifying equivocal results as negative. The best diagnostic parameters were found using the Enzygnost-2 assay in the first tier, followed by a C6-ELISA in the second tier (sensitivity 77.6%, 95% CI 71.7–82.9; specificity 96.1%, 95% CI 92.7–98.2). This algorithm performed significantly better than the equivalent STTT algorithm in terms of sensitivity (p < 0.001), while maintaining comparable specificity (population controls p = 0.617). Our results show that MTTT can be a useful tool for the serodiagnosis of European patients with early Lyme borreliosis.

在美国患者的样本中，与标准的两层检测（STTT）相比，针对莱姆病的改良的两层检测（MTTT）（即用EIA代替免疫印迹进行确认）具有更高的敏感性。本研究评估了MTTT的各种算法在欧洲红斑病（EM）患者中的敏感性和特异性，该患者是早期莱姆病患者的模型疾病，并在适当的对照组中进行了研究。在第一层中使用了四种不同的免疫测定，然后进行了免疫印迹或C6-EIA，或被用作独立的单层检测。这些测试是在一般情况下，对228位荷兰医生诊断为EM的荷兰患者的连续血清进行的，其中231名来自普通人群，50个具有潜在交叉反应抗体的对照。与同等的STTT相比，所研究的MTTT的所有变体均具有明显更高的灵敏度，同时保留了相当的特异性。在MTTT算法中，将模糊结果分类为阳性比将模糊结果分类为阴性产生更好的诊断参数。在第一级使用Enzygnost-2测定法发现最佳诊断参数，然后在第二级使用C6-ELISA（灵敏度77.6％，95％CI 71.7–82.9；特异性96.1％，95％CI 92.7–98.2） 。就灵敏度而言，该算法的性能明显优于等效的STTT算法（在MTTT算法中，将模糊结果分类为阳性比将模糊结果分类为阴性产生更好的诊断参数。在第一级使用Enzygnost-2测定法发现最佳诊断参数，然后在第二级使用C6-ELISA（灵敏度77.6％，95％CI 71.7–82.9；特异性96.1％，95％CI 92.7–98.2） 。就灵敏度而言，该算法的性能明显优于等效的STTT算法（在MTTT算法中，将模糊结果分类为阳性比将模糊结果分类为阴性产生更好的诊断参数。在第一级使用Enzygnost-2测定法发现最佳诊断参数，然后在第二级使用C6-ELISA（灵敏度77.6％，95％CI 71.7–82.9；特异性96.1％，95％CI 92.7–98.2） 。就灵敏度而言，该算法的性能明显优于等效的STTT算法（p  <0.001），同时保持相当的特异性（人群对照p  = 0.617）。我们的结果表明，MTTT可以作为欧洲早期莱姆病患者的血清学诊断的有用工具。