弓形虫脑病在HIV/AIDS中患病的危险因素和MRI特征分析

Risk factors and MR characteristics of toxoplasma encephalopathy in HIV/AIDS

目的探讨HIV/AIDS患者罹患弓形虫脑病的危险因素,总结弓形虫脑病的MRI特征。方法采用病例-对照研究,按照年龄、性别进行11配对,病例组纳入标准为穿刺活检病理证实或参照血清IgG抗体阳性予以试验性抗弓形虫治疗2周后好转,对照组选择同期住院的HIV/AIDS患者。采用11配对Logistic回归模型进行危险因素分析。以CD4^+细胞计数水平100个/ul为界,分析不同水平的MRI特征的差异。结果共收集两组各21例,通过条件Logistic回归分析调整其他影响因素后,未行HAART治疗是HIV/AIDS患者罹患弓形虫脑病危险因素,相对危险比(RR)为6.5。对病例组21例患者的188个病灶MRI特征进行统计分析,依据CD4^+细胞计数100个/ul为界分为两组,两组间病灶形态存在统计差异(χ^2=8.937,P=0.003)。CD4^+细胞计数大于≥100个/ul时,病灶全部为斑片或环形14个(100%);CD4^+细胞计数<100个/ul时,病灶结节、斑片或环形比例相当,分别为70个(40.2%)、104个(50.9%)。“偏心靶征”12个(6%)见于CD4^+细胞计数<小于100个/ul时。对1cm以上的病变强化“环”的内缘和外缘可见DWI高信号,相应ADC图为低信号,中心弥散不受限或受限,随着延迟时间的延长强化“环”的厚度增加。结论未行HAART治疗是HIV/AIDS患者罹患弓形虫脑病的危险因素,不同CD4^+细胞计数水平,弓形虫脑病磁共振影像存在一定特征性。

Objective To investigate the risk factors of toxoplasma encephalopathy in HIV/AIDS patients and to summarize the MR characteristics of toxoplasma encephalopathy.Methods A case-control study was conducted,and 11 matches were conducted according to age and gender.The inclusion criteria of the case group were pathological confirmation by puncture biopsy or improvement after 2 weeks of experimental anti-toxoplasma therapy with reference to positive serum IgG antibody.HIV/AIDS patients hospitalized at the same time in the control group were selected.Risk factors were analyzed by 11 paired Logistic regression model.The CD4^+ cell count level of 100 cells per ul was bounded to analyze the differences of MR characteristics at different levels.Results A total of 21 cases in each group were collected.After adjusting other influencing factors through conditional Logistic regression analysis,the relative risk ratio(RR)of HIV/ARDS patients without HAART treatment was 6.5.MR characteristics of 188 lesions of 21 patients in the case group were statistically analyzed.They were divided into two groups according to CD4^+cell counts 100 cells per ul,and the morphology of lesions was statistically different between the two groups(χ^2=8.937,P=0.003).When CD4^+cell count was greater than or equal to 100 cells per ul,all lesions were patches or annular 14(100%).When CD4^+ cell count was less than 100 cells per ul,there were 70(40.2%)and 104(50.9%)nodules,plaques or rings,respectively.Twelve(6%)"eccentric targets"were found when CD4^+cell count was less than 100 cells per ul.High DWI signal can be seen on the inner and outer edges of the enhanced"ring"for lesions over 1 cm,and the corresponding ADC map showed low signal,with no or limited central diffusion,and the thickness of the enhanced"ring"increasesd with the extension of the delay time.Conclusion The absence of HAART therapy is a risk factor for toxoplasma encephalopathy in HIV/AIDS patients.Different CD4^+ cell count levels have certain characteristics in magnetic resonance imaging of toxoplasma encephalopathy.