鸟-胞内分枝杆菌复合群鸟和胞内分枝杆菌亚种对20种药物的敏感性特征及亚种间药物敏感性比较

目的分析鸟-胞内分枝杆菌复合群鸟分枝杆菌亚种和胞内分枝杆菌亚种对20种药物的敏感性特征及比较2个亚种间的药物敏感性差异。方法用微孔板Alamar blue显色法分别检测97株鸟分枝杆菌和172株胞内分枝杆菌对克拉霉素、卷曲霉素和利福布丁等20种药物的最小抑菌浓度,判断其敏感性,分析2个亚种菌株对20种药物的敏感性特征以及对利福霉素类、氨基糖苷类和大环内酯类内药物的交叉耐药性,并比较2个亚种对20种药物的敏感性差异。结果对鸟分枝杆菌敏感率高于80%的药物依次是卷曲霉素(100%,97/97)、阿米卡星(97.9%,95/97)、利福布丁(96.9%,94/97)、利福平和卡那霉素(83.5%,81/97)及克拉霉素(82.5%,80/97);对胞内分枝杆菌敏感率高于80%的药物依次是阿米卡星(99.4%,171/172)、卡那霉素(95.9%,165/172)、利福布丁(95.4%,164/172)、克拉霉素(94.2%,162/172)、氯法齐明(87.2%,150/172)、卷曲霉素和罗红霉素(86.1%,148/172)及利福喷丁(82.6%,142/172)。97株鸟分枝杆菌分别有1株、1株和17株而172株胞内分枝杆菌中分别有0株、7株和6株同时对氨基糖苷类、利福霉素类和大环内酯类内各种药物同时耐药或中度敏感。鸟分枝杆菌对利福平和卷曲霉素的敏感率明显高于胞内分枝杆菌。胞内分枝杆菌对利福喷丁、妥布霉素、卡那霉素、乙胺丁醇、莫西沙星、克拉霉素、阿奇霉素和罗红霉素的敏感率均高于鸟分枝杆菌。结论鸟和胞内分枝杆菌均对卷曲霉素、阿米卡星、利福布丁和克拉霉素敏感性较高,对胞内分枝杆菌敏感的药物多于鸟分枝杆菌,利福喷丁仅对胞内分枝杆菌抗菌性较好,而利福平仅对鸟分枝杆菌抗菌性较好,乙胺丁醇对两个亚种敏感性均较差;对同一种类的药物做药物敏感性试验可为临床医生治疗鸟或胞内分枝杆菌感染选择合适的替代药物做依据。

Drug susceptibility patterns and comparism on susceptibility in Mycobacterium avium-intracellulare complex subspecies Mycobacterium avium and Mycobacterium intracellulare against 20 drugs

Drug susceptibility testing (DST) with microplate Alamar Blue assay was peformed in 97 Mycobacterium avium and 172 Mycobacterium intracellulare of Mycobacterium avium-intracellulare complex (MAC) against 20 drugs. The susceptibility and resistance patterns of each strains were then defined, and the susceptibility patterns of each subspecies were analysed and then compared between M. avium and M. intracellulare clinical isolates. The results shown that the drugs which were susceptible to more than 80% M. avium clinical isolates were capreomycin (100%), amikacin(97.9%), rifabutin (96.9%), rifampicin or kanamycin (83.5%) and clarithromycin (82.5%); the drugs which were susceptible to more than 80% M. intracellulare clinical isolates were amikacin (99.4%), kanamycin (95.9%), rifabutin (95.4%), clarithromycin (94.2%), clofazimine (87.2%), capreomycin or roxithromycin (86.1%) and rifapentine (82.6%). There were one, one and 17 out of 97 M. avium resistant to the drugs of the aminoglycosides, the rifamycins and the macrolides tested, respectively, whilst there were zero, seven and six out of 172 M. intracellulare simutaneously resistant to the aminoglycosides, the rifamycins and the macrolides, respectively. The susceptibility frequency of M. avium to rifampicin and capreomycin were significantly higher than that of M. intracellulare. The susceptibility frequency of M. intracellulare to rifapentine, tobramycin, kanamycin, ethambutol, moxifloxacin, clarithromycin, azithromycin and roxithromycin were significantly higher than that of M.avium. Both M. avium and M. intracellulare showed excellent susceptibility to capreomycin, amikacin, rifabutin and clarithromycin. The number of drugs that M. intracellulare were susceptible to were more than that M. avium susceptible to. Rifapentine were only found to have good antibacterial activity against M. intracellulare but not M. avium, whilst rifampicin was in contrast. Both MAC subspecies showed low susceptibility to ethambutol. DST on the drugs belonging to the same category could supply clues for clinicians choosing substitutes when treating M. avium and M. intracellulare infectious diseases.