Krüüner Annika, Pehme Lea, Ghebremichael Solomon, Koivula Tuija, Hoffner Sven E, Mikelsaar Marika
Institute of Microbiology, Tartu University, Estonia.
Clin Infect Dis. 2002 Jul 15;35(2):146-55. doi: 10.1086/340980. Epub 2002 Jun 14.
We investigated the means by which drug resistance emerges among drug-susceptible Mycobacterium tuberculosis strains during antituberculosis therapy. Patients who experienced failure of treatment for active pulmonary tuberculosis, who initially received diagnoses of infection with drug-susceptible M. tuberculosis, and who had had at least 3 isolates tested for drug susceptibility were selected from a 6-year period in the Estonian National Reference Laboratory archive. Eleven patients from whom 35 sequential isolates of M. tuberculosis had been obtained were recruited into the study. Their clinical data and treatment charts were analyzed and correlated with drug-susceptibility patterns and IS6110 restriction fragment-length polymorphism (RFLP) profiles. Six patients excreted isogenic drug-susceptible M. tuberculosis strains, whereas, in the other 5 patients, the isolated strain shifted from a susceptible to a resistant phenotype. In all cases, this shift correlated to a shift in RFLP pattern, which showed reinfection with a new strain. Exogenous reinfection with drug-resistant M. tuberculosis may be misinterpreted as the emergence of drug resistance if molecular testing techniques are not used.
我们研究了抗结核治疗期间药物敏感的结核分枝杆菌菌株产生耐药性的方式。从爱沙尼亚国家参考实验室档案中6年期间选取了患有活动性肺结核治疗失败、最初被诊断为感染药物敏感结核分枝杆菌且至少有3株菌株进行药敏试验的患者。招募了11名患者，从他们身上获取了35株连续的结核分枝杆菌菌株用于研究。分析了他们的临床数据和治疗图表，并将其与药敏模式以及IS6110限制性片段长度多态性（RFLP）图谱相关联。6名患者排出了同基因的药物敏感结核分枝杆菌菌株，而在其他5名患者中，分离出的菌株从敏感表型转变为耐药表型。在所有病例中，这种转变与RFLP模式的转变相关，表明再次感染了新菌株。如果不使用分子检测技术，耐药结核分枝杆菌的外源性再次感染可能会被误诊为耐药性的出现。
