近期肺炎衣原体感染与强直性脊柱炎疾病活动的研究

Investigation of relationship between recent chlamydia pneumoniae infection and active ankylosing spondylitis

目的研究近期肺炎衣原体感染与强直性脊柱炎（As）疾病活动的关系。方法测定79例门诊As患者和73名健康者血中lgM、lgA和IgG抗肺炎衣原体抗体（CpIgA，CplgM和CpIgG）。收集临床和实验室资料以及疾病活动指数（BASDAI）。阳性CpIgM或CpIgA抗体被认为存在近期肺炎衣原体感染。Wilcoxon检验膏检验、Fisher确切概率法、t检验、方差分析和多因素回归分析用于数据分析。结果89％（70／79）的As患者和92％（67／73）的健康者均存在CpIgG抗体，但As患者CpIgA和CpIgM阳性率[分别为52％（41／79）、80％（63／79）]明显高于健康者[分别为32％（23／73）、21％（15／73）]x2=6．61，P=0．010；x2=44．0，P〈0．01）。其中CplgM相对危险度（0R）=17．1，95％可信区间（c，）7．4～39．5；CpIgA的OR：3．1，95％CI1．3-7．2。此外，阳性CpIgM抗体与疾病活动有关，且CpIgM转阴伴随疾病活动指数下降。CpIgM或CpIgA与外周关节病变和肌腱附着点无关。结论近期肺炎衣原体感染与AS高度相关，CplgM抗体与疾病活动有关，提示近期肺炎衣原体感染是诱发AS疾病活动的关键因素之一。

Objective To investigate the relationship between recent chlamydia pneumoniae （Cp） infection and active ankylosing spondylitis （AS）. Methods Seventy nine AS outpatients and 73 normal controls （NC） were enrolled into this study. Serum anti-Cp antibodies （Cplg） were tested using the enzyme- linked immunosorbent assay （ELISA）. Clinical and experimental data were collected. Patients with positive CplgM or CplgA were considered as having a recent Cp infection. Wilcoxon test, Student＇s t test, X2 test and multivariate logistic regression were used for statistical analysis. Results Both AS patients and normal controls had a high prevalence for sero-positive CplgG, which was 89%（70/79） vs 92%（67/73） respectively, while AS patients had a higher frequency of CplgA and CplgM when compared with NC I52%（41/79） vs 32% （23/73）, X2=6.61, P=0.010 for CplgA; 80%（63/79） vs 21%（15/73）, X2=44.031, P〈0.01 for CplgM]. The presence of CplgM or CplgA favored AS, the OR was 17.1 （95%CI 7.4-39.5）, or 3.1 （95%CI 1.3-7.2）, respectively. In addition, CplgM was associated with disease activity parameters including ESR （x2=2.56, P= 0.021 ）, CRP 0（2=7.28, P=0.007） and BASDAI （x2=6.79, P=0.009）. Furthermore, consecutive positive Cp!gM favored the persistent active or relapsed disease, while negative CplgM favored a reduced disease activity. There was no correlation between CplgM/CplgA and peripheral joint disease and enthesitis. Conclusion Recent Cp infection is highly associated with AS and CplgM antibody relates with active AS, which indicates that Cp infections may be a critical triggering factor for active AS.