Abstract：
OBJECTIVE: We examined the frequency of cross-reactions to Rickettsia typhi in patients with Japanese spotted fever (JSF) and evaluated the differences between two rickettsiae using antibody endpoint titers.
METHODS: Patients\' immunoglobulin (Ig)M and IgG titers against Rickettsia japonica and Rickettsia typhi in two phases were measured using an indirect immunoperoxidase assay at two reference centers for rickettsiosis in Japan. Cross-reaction was defined as a higher titer against R. typhi in convalescent sera than in acute sera among patients fulfilling the criteria for JSF diagnosis. The frequencies of IgM and IgG were also evaluated.
RESULTS: Approximately 20% of cases showed positive cross-reactions. A comparison of antibody titers revealed the difficulty in identifying some positive cases.
CONCLUSIONS: Cross-reactions of 20% in serodiagnosis may lead to the misclassification of rickettsial diseases. However, with the exception of some cases, we were able to successfully differentiate JSF from murine typhus using each endpoint titer.
METHODS: Patients\' immunoglobulin (Ig)M and IgG titers against Rickettsia japonica and Rickettsia typhi in two phases were measured using an indirect immunoperoxidase assay at two reference centers for rickettsiosis in Japan. Cross-reaction was defined as a higher titer against R. typhi in convalescent sera than in acute sera among patients fulfilling the criteria for JSF diagnosis. The frequencies of IgM and IgG were also evaluated.
RESULTS: Approximately 20% of cases showed positive cross-reactions. A comparison of antibody titers revealed the difficulty in identifying some positive cases.
CONCLUSIONS: Cross-reactions of 20% in serodiagnosis may lead to the misclassification of rickettsial diseases. However, with the exception of some cases, we were able to successfully differentiate JSF from murine typhus using each endpoint titer.
摘要：
目的：我们检查了日本斑点热（JSF）患者对伤寒立克次体的交叉反应频率，并使用抗体终点滴度评估了两种立克次体之间的差异。
方法：在日本的两个立克次体病参考中心使用间接免疫过氧化物酶测定法测量了两个阶段的患者针对日本立克次体和伤寒立克次体的免疫球蛋白（Ig）M和IgG滴度。交叉反应定义为在符合JSF诊断标准的患者中，恢复期血清中抗伤寒R.还评估了IgM和IgG的频率。
结果：大约20%的病例显示阳性交叉反应。抗体滴度的比较表明，难以识别某些阳性病例。
结论：血清诊断中20％的交叉反应可能导致立克次体疾病的分类错误。然而,除了某些情况，我们能够使用每个终点滴度成功区分JSF和鼠斑疹伤寒.
方法：在日本的两个立克次体病参考中心使用间接免疫过氧化物酶测定法测量了两个阶段的患者针对日本立克次体和伤寒立克次体的免疫球蛋白（Ig）M和IgG滴度。交叉反应定义为在符合JSF诊断标准的患者中，恢复期血清中抗伤寒R.还评估了IgM和IgG的频率。
结果：大约20%的病例显示阳性交叉反应。抗体滴度的比较表明，难以识别某些阳性病例。
结论：血清诊断中20％的交叉反应可能导致立克次体疾病的分类错误。然而,除了某些情况，我们能够使用每个终点滴度成功区分JSF和鼠斑疹伤寒.
