2017—2018年陕西省涂阳肺结核患者临床分离株的耐药性检测结果分析

目的 了解陕西省涂阳肺结核患者临床分离株的耐药情况。方法 采用整群随机抽样(抽签法)在陕西省选取26个调查点,收集2017年1月至2018年12月各调查点新登记涂阳肺结核患者的临床分离株987株。987株分枝杆菌经菌种鉴定,非结核分枝杆菌(NTM)为22株(2.23%,22/987),结核分枝杆菌(MTB)为965株(97.77%,965/987)。采用比例法药物敏感性试验(简称“药敏试验”)对965株MTB进行6种抗结核药物的耐药性检测,药物包括异烟肼(INH)、利福平(RFP)、乙胺丁醇(EMB)、链霉素(Sm)、氧氟沙星(Ofx)、卡那霉素(Km)。应用SPSS 18.0软件进行统计学分析,计数资料采用χ²检验或Fisher精确检验,P<0.05为差异有统计学意义。结果 965株MTB的耐药率为28.50%(275/965),初治和复治患者的耐药率分别为26.07%(219/840)和44.80%(56/125);单耐药率为14.30%(138/965),初治和复治患者分别为14.76%(124/840)和11.20%(14/125);多耐药率为4.56%(44/965),初治和复治患者分别为4.40%(37/840)、5.60%(7/125);耐多药率为6.53%(63/965),初治和复治患者分别为4.40%(37/840)和20.80%(26/125);广泛耐药率为0.62%(6/965),初治和复治患者分别为0.24%(2/840)和3.20%(4/125);RFP耐药率为9.84%(95/965),初治和复治患者分别为7.14%(60/840)和28.00%(35/125)。复治患者的耐药率、耐多药率和RFP耐药率均明显高于初治患者,差异均有统计学意义(χ²值分别为18.730、47.930、53.331,P值均为0.000)。对一线和二线抗结核药物的耐药率分别为26.01%(251/965)和8.50%(82/965)。6种抗结核药物耐药顺位为Sm(17.62%,170/965)>INH(15.03%,145/965)>RFP(9.84%,95/965)>Ofx(6.84%,66/965)>EMB(5.08%,49/965)>Km(2.59%,25/965)。耐药谱有39种类型,其中单耐药6种,多耐药5种,耐多药13种(含广泛耐药3种),含二线药的多耐药组合15种。结论 陕西省近年耐药结核病防控工作取得了一定成效,但耐药谱呈现多态性和复杂性,耐多药和利福平耐药疫情依然严峻。

Analysis of drug resistance of clinical isolates of smear positive pulmonary tuberculosis patients in Shaanxi Province from 2017 to 2018

Objective To explore the drug resistance of Mycobacterium tuberculosis(MTB) isolated from smear-positive pulmonary tuberculosis (TB) patients in Shaanxi Province.Methods Twenty-six survey points in Shaanxi Province were extracted with stratified cluster random sampling. All the culture positive isolated strains from new smear positive pulmonary TB patients registered from January 2017 to December 2018 were collected. Twenty-two strains were identified as non-tuberculosis mycobacteria (NTM) which accounted for 2.23% (22/987), and 965 strains were identified as MTB which accounted for 97.77% (965/987). Drug susceptibility test of 6 anti-TB drugs (including isoniazid (INH), rifampicin (RFP), ethambutol (EMB), streptomycin (Sm), ofloxacin (Ofx), kanamycin (Km)) with proportional method were performed on 965 strains of MTB. SPSS 18.0 was used for statistical analysis, and the counting data were analyzed by Chi-square test or Fisher exact test. P<0.05 was considered statistically significant.Results The drug resistance rate of 965 MTB strains was 28.50% (275/965), 26.07% (219/840) for initially-treated patients and 44.80% (56/125) for re-treated patients. The mono-resistance rate was 14.30% (138/965), 14.76% (124/840) for initially-treated patients and 11.20% (14/125) for re-treated patients. The poly-drug resistance rate was 4.56% (44/965), 4.40% (37/840) for initially-treated patients and 5.60% (7/125) for re-treated patients. The multi-drug resistance rate was 6.53% (63/965), 4.40% (37/840) for initial patients and 20.80% (26/125) for re-treated patients. The extensive drug resistance rate was 0.62% (6/965), 0.24% (2/840) for initially-treated patients and 3.20% (4/125) for re-treated patients. The rifampicin resistance rate was 9.84% (95/965), 7.14% (60/840) for initially-treated patients and 28.00% (35/125) for re-treated patients. The drug resistance rate, multi-drug resistance rate and rifampicin resistance rate of re-treated patients were significantly higher than those of initially-treated patients (χ²=18.730, 47.930 and 53.331 respectively, all P=0.000). The drug resistance rate to 4 first-line and 2 second-line anti-TB drugs were 26.01% (251/965) and 8.50% (82/965), respectively. It showed the highest resistance to Sm (17.62%, 170/965), followed by INH (15.03%, 145/965), RFP (9.84%, 95/965), Ofx (6.84%, 66/965), EMB (5.08%, 49/965) and Km (2.59%, 25/965).There were 39 types of drug resistance spectrum, which included 6 mono-resistance, 5 poly-drug resistance, 13 multi-drug resistance and 15 kinds of poly-drug resistance of second-line drugs.Conclusion In recent years, some achievements have been made in the prevention and control of drug-resistant TB in Shaanxi Province, but the drug resistance spectrum presents polymorphism and complexity, and the epidemic of multi-drug resistance and rifampicin resistance is still severe.