安徽省非结核分枝杆菌临床分离率及人群分布和耐药性分析

Analysis of the clinical isolation rate,population distribution and drug resistance of non-tuberculous mycobacteria in Anhui

目的分析安徽省非结核分枝杆菌(NTM)临床分离率和人群分布及耐药性情况,为NTM的防治提供科学依据。方法按照分层整群抽样方法从全省86个结核病门诊抽取42个调查点,连续纳入2015年9月15日至2016年8月31日的涂阳疑似肺结核患者3047例,对痰标本酸性罗氏培养阳性的2652株菌株行菌种鉴定[对硝基苯甲酸(PNB)培养和早期分泌蛋白(MPB64)胶体金法]和基因测序(16S rRNA和hsp65 DNA测序),再对其中的NTM临床分离株在不同人群中的分布特征和耐药性检测(微孔板法)进行研究和分析。结果2652株培养阳性菌株经初步菌种鉴定获得122株NTM菌株,进一步经基因测序获得NTM临床分离株107株[符合率为87.70%(107/122),分离率为4.03%(107/2652)]、结核分枝杆菌12株、诺卡菌1株、污染菌2株;其中107株NTM共计分离出6种优势菌种,以胞内分枝杆菌[65.42%(70/107)]和脓肿分枝杆菌[25.23%(27/107)]为主。NTM菌株在复治[9.26%(41/443)]、女性[6.32%(39/617)]、≥40岁[5.11%(100/1956)]、退休[8.82%(12/136)]和农民[4.38%(86/1965)]、初中及以下学历([4.43%(97/2189)]、家庭年收入<2万元[4.98%(75/1506)]人群中的分离率均明显高于初治[2.99%(66/2209)]、男性[3.34%(68/2035)]、<40岁[1.01%(7/696)]、工人[0.96%(1/104)]、高中及以上[2.16%(10/463)]、家庭年收入≥2万元[2.83%(27/955)]者[χ^2值分别为37.434、10.854、36.387、17.021、18.995、8.748,P值分别为0.000、0.001、0.000、0.002、0.001、0.033]。104株(排除1株复苏失败的胞内分枝杆菌、1株草分枝杆菌和1株马赛分枝杆菌)菌株的药物敏感性试验结果显示,不同NTM对阿米卡星、利福布汀、克拉霉素和利福平的敏感度较高[分别为87.50%(91/104)、86.54%(90/104)、83.65%(87/104)、75.00%(78/104)],对亚胺培南/西司他丁、头孢西丁、米诺环素、多西环素等的耐药率较高[分别为100.00%(104/104)、95.19%(99/104)、94.23%(98/104)、93.27%(97/104)]。结论安徽省NTM的分离率较低,以复治、女性、40岁及以上、农民、低学历、低收入人群为主,且耐药率较高,应提升实验室鉴别和监测NTM的水平。

Objective To analyze the clinical isolation rate,population distribution and drug resistance of non-tuberculous mycobacteria(NTM)in Anhui to provide a scientific basis for the prevention and treatment of NTM.Methods Using the stratified cluster sampling method,42 investigation points were collected from86 tuberculosis clinics in Anhui,and 3047 cases of smear-positive suspected pulmonary tuberculosis patients from September 15,2015 to August 31,2016 were continuously included.The 2652 positive strains with acid L-G medium were identified for strains(p-nitrobenzoic acid(PNB)culture and early secreted protein(MPB64)colloidal gold method)and gene sequencing(16 S rRNA and hsp65 DNA sequencing),and then the NTM was clinically isolated.The distribution characteristics and drug resistance detection(microplate method)of strains in different populations were studied and analyzed.Results The 2652 culture-positive strains obtained 122 NTM strains through preliminary strain identification;and by genetic sequencing,107 NTM clinical isolates(the coincidence rate was 87.70%(107/122),and the isolation rate was 4.03%(107/2652)),12 strains of Mycobacterium tuberculosis,1 strain of Nocardia,and 2 strains of contaminated bacteria were further obtained.Among them,a total of 6 dominant bacterial species were isolated from the 107 strains of NTM,mainly of Mycobacterium intracellulare(65.42%(70/107))and Mycobacterium abscessus(25.23%(27/107)).The rate of NTM isolation in retreatment(9.26%(41/443)),female(6.32%(39/617)),40 years old and above(5.11%(100/1956)),retirement(8.82%(12/136))and farmers(4.38%(86/1965)),junior high school and below(4.43%(97/2189))and family annual income<20000 CNY(4.98%(75/1506))were significantly higher than those in the initial treatment(2.99%(66/2209)),male(3.34%(68/2035)),under 40 years old(1.01%(7/696)),workers(0.96%(1/104)),high school and above(2.16%(10/463)),and family annual income≥20000 CNY(2.83%(27/955))(χ^2 values were 37.434,10.854,36.387,17.021,18.995 and 8.748,respectively;P values were 0.000,0.001,0.000,0.002,0.001 and 0.033,respectively).The drug susceptibility test results of 104 strains(excluding 1 strain of Mycobacterium intracellulare,1 strain of Mycobacterium phlei,and 1 strain of Mycobacterium marseille which were failed to recover)showed that amikacin,rifabutin,clarithromycin and rifampicin were more sensitive(87.50%(91/104),86.54%(90/104),83.65%(87/104)and 75.00%(78/104),respectively),the resistance rates to imipenem/cilastatin sodium,cefoxitin,minocycline,doxycycline,etc.were higher(100.00%(104/104),95.19%(99/104),94.23%(98/104)and 93.27%(97/104),respectively).Conclusion The isolation rate of NTM in Anhui is lower,mainly in the retreatment,females,40 years old and above,farmers,less educated and low income.The drug resistance rate is high,the laboratory identification and monitoring of NTM should be improved.