Bactec 9120系统检测382例需氧血培养结果分析

Analysis or 382 Cases of Aerobic Blood Culture by Bactec 9120 System

用Ｂａｃｔｅｃ９１２０全自动血培养系统检测了３８２例需氧血培养标本，分离出的病原菌用ＶｉｔｅｋＡＭＳ－３２进行鉴定和药敏试验。结果，系统阳性报警７７例，其中７１例分离出病原菌３０种７１株，平均阳性报警时间为２８．４ｈ。病原菌中葡萄球菌８种３７株，其中凝固酶阴性葡萄球菌（ＣＮＳ）３２株，耐甲氧西林葡萄球菌（ＭＲＳ）２２株。其余６例为假阳性报警，其模拟生长曲线多没有明显的对数生长期。阴性报警标本转种均无细菌生长。已用抗生素治疗病人的血培养，树脂瓶的阳性率高于普通瓶。表明，细菌增殖速度是影响系统阳性报警时间的重要因素。培养瓶选择不当可导致系统不能检测的假阴性。模拟生长曲线有助于鉴别假阳性报警。ＣＮＳ已成为当前菌（败）血症的重要病原菌。

Blood samples from 382 cases were aerobicly cultured by Bactec 9120 system. Pathogens isolated from thesamples were identified on Vitek AMS-32. The results showed that 71 strains of 30 species of pathogens were isolated from 71 of 77 samples with positive alarm, and the average time of detection was 28. 4 h. Of all isolatedpathogens, there were 37 strains of & species of staphylococcus [32 strains of coagulase-negative staphylococcus(CNS) and 22 strains of methicillin resistant staphylococcus (MRS)]. No pathogens were isolated from all samples with negative alarm and the other 6 samples with positive alarm which had no obvious logarithmic growthphases and had been confirmed as false positive alarms. The results also showed that the recovery rate of the resincontaining vials was higher than that of the standard vials on patients being treated with antibiotics. It indicatedthat the proliferative speed of organism was an important factor affecting the time of positive alarm, and the reasonable selection of vials could improve the recovery rate. The simulated growth curves could be used to distinguish the false positive alarm, and CNS had become important pathogens of bacteremia and septicemia at present.