摘要目的 了解儿童社区获得性肺炎(CAP)中支原体肺炎的临床及影像学特点,以及阿奇霉素体外耐药菌株所致支原体肺炎的治疗效果.方法 前瞻性连续入选首都医科大学附属北京朝阳医院儿科病房2010年9月1日至2011年8月31日收治的179例CAP患儿,均进行咽分泌物肺炎支原体核酸检测及肺炎支原体体外培养,培养阳性者进行体外药物敏感度测定.结果 179例CAP中确诊支原体肺炎的患儿83例(46％),肺炎支原体培养阳性45例,其中44株体外药敏试验结果显示对大环内酯类药物高度耐药(MR),1例大环内酯体外敏感.44例MR肺炎患儿的临床表现为持续性发热、咳嗽,大多为高热[(39.5±0.7)℃],咳嗽呈刺激性干咳；外周血白细胞大多正常[(8±4)×109/L],中性粒细胞比例正常或升高(0.60±0.94),ESR[(24± 14) mm/1 h]及C反应蛋白(12.8 mg/L)均增高.44例MR肺炎X线胸部正位片显示大叶性实变影10例(23％,10/44),其中左下肺3例,左肺2例,右下肺3例,右上肺2例；少量胸腔积液1例合并右下肺实变；斑片样炎性渗出影27例；肺纹理增重7例.44例MR肺炎支原体肺炎患者中19例进行了胸部CT检查,13例存在肺叶或肺段实变.44例MR肺炎平均在发病第4天接受阿奇霉素治疗,平均疗程为(9±4)d.12例初选抗生素为头孢或青霉素(1例青霉素),41例使用阿奇霉素过程中联合使用头孢或青霉素类抗生素(1例联合青霉素类抗生素).阿奇霉素治疗后平均发热时间为(6±3)d；治疗后咳嗽持续时间为(17±5)d；将44例MR肺炎患儿根据肺部影像学检查分为大叶性肺实变组及无肺实变组,大叶性肺实变组患儿发热时间及给予大环内酯类药物(阿奇霉素)后发热时间均较非实变组长,差异有统计学意义(P＜0.05).结论 肺炎支原体对大环内酯的耐药率高达98％ (44/45).MR感染合并大叶性肺实变者发热时间及给予大环内酯类药物后发热时间较非肺实变者延长.本组44例MR肺炎患儿预后良好,无肺外严重并发症.

abstractsObjective To investigate the drug resistance of Mycoplasma pneumoniae among children with community-acquired pneumonia (CAP),and to explore the clinical and radiological characteristics of and the role of azithromycin in the treatment of of macrolide-resistant (MR) Mycoplasma pneumoniae pneumonia.Methods Cases of CAP in children (n =179) were prospectively enrolled in the Pediatric ward of Beijing Chaoyang Hospital from 1 st September,2010 to 31st August 2011.Pharyngeal swabs were collected for detection of Mycoplasma pneumoniae DNA.Mycoplasma pneumoniae culture and in vitro susceptibility testing were also performed.Results Eighty-three cases met the diagnostic criteria of mycoplasma pneumonia,accounting for 46％ of the CAP patients.Mycoplasma pneumoniae culture was positive in 45 cases,including 44 highly resistant to macrolides (MR) in vitro,and 1 sensitive.The 44 cases caused by MR pathogen presented with fever for (8 ± 3) d and cough for (17 ± 5) d,with higher fever (39.5 ± 0.7) ℃ and more irritating dry cough.In most of the children,peripheral blood leukocytes (8 ± 4) × 109/L were normal,with normal or elevated (0.60 ± 0.94) neutrophils,normal or slightly elevated erythrocyte sedimentation rate [(24 ± 14) mm/1 h] and CRP (12.8 mg/L).Chest X-ray showed lobar consolidation in 10 cases (23％,10/44),among them 3 in the lower left lung,2 in the left lung,3 in the right lower lung,2 in the right upper lung.Pleural effusion (small amount),combined with right lower lung consolidation,was found in 1 case.Patchy shadows were found in 27 cases,and interstitial lung infiltrate in 7 cases.Of the 44 cases caused by MR Mycoplasma pneumoniae,19 had lung computed tomography (CT) scanning,among them 13 had lobar or segmental consolidation.Azithromycin therapy started in an average of 4.0 days after onset of illness,with duration of therapy averaging (9 ± 4) d.Cephalosporin or penicillin (n =1) was the initial antibiotic choice in 12 of them,while combination therapy with azithromycin and cephalosporin or penicillin antibiotics was given in 41 of them.The duration of fever averaged (6 ± 3) d after treatment of azithromycin and duration of cough averaged (17 ± 5) d after treatment.Among patients with MR Mycoplasma pneumonia,those with lobar consolidation had longer duration of fever after treatment with azithromycin,compared with those without consolidation (P ＜ 0.05).Conclusions The macrolide resistance rate was 98％ (44/45) in our patients.Fever and duration of therapy with azithromycin in MR infection was longer in patients with lobar consolidation.The 44 children with MR Mycoplasma pneumonia recovered with no serious complications.