目的 利用基质辅助激光解吸电离飞行时间质谱系统(VITEK-MS)对体液培养阳性瓶进行直接鉴定,探索快速诊断临床致病菌的新策略。方法 收集体液培养阳性瓶,不经琼脂平板培养,直接利用VITEK-MS进行鉴定,并与传统生化鉴定的方法进行比较分析。结果 50例体液培养阳性瓶中,传统细菌鉴定法检出47株阳性菌,3例阴性;而VITEK-MS直接鉴定法检出31株阳性菌,同样3例阴性。VITEK-MS直接鉴定法灵敏度达65.96%,特异度为100%,临床符合率为68%。鉴定时间从24小时缩短到2小时。结论 利用VITEK-MS质谱系统直接鉴定体液培养阳性标本中的病原菌,能有效缩短细菌鉴定时间,准确快速地诊断临床致病菌。
Objective To find a fast method for detection of pathogens in positive culture bottles by using the VITEK-MS system. Methods VITEK-MS microbial identification system was used to directly identify the bacteria in the positive culture bottles, without culture on agar plates. The identification results were further compared with those by the traditional biochemical identification. Results Forty-seven bacterial strains were identified by traditional biochemical methods among 50 positive culture bottles, and 3 of them were negative. Of these 50 samples, thirty-one bacterial strains were identified by VITEK-MS and 3 were also negative. The sensitivity and specificity for direct VITEK-MS identification were 65.96% and 100%, and the clinical coincidence rate was 68%. The turn around time for identification was reduced from 24 to 2 hours. Conclusion Direct identification of bacterial pathogens in positive culture bottles by VITEK-MS could reduce turn around time, and lead to accurate and fast diagnosis.
目的 了解河源市无偿献血人群中丙型肝炎病毒(HCV)感染情况及HCV感染合并乙型肝炎病毒(HBV)、人类免疫缺陷病毒(HIV)以及梅毒螺旋体(TP)感染的情况,为当地预防和控制输血传播性疾病提供实验室依据。方法 选择2010年1月1日—2015年12月31日河源市中心血站无偿献血者71 618例,采用酶联免疫吸附试验(ELISA)方法检测其血浆抗-HCV、乙型肝炎表面抗原(HBsAg)、抗-TP及HIV(Ag/Ab),统计分析抗HCV阳性无偿献血者合并感染HBV、HIV和TP的情况。结果 71 618例无偿献血者标本中抗-HCV、HBsAg 、抗-TP及HIV(Ag/Ab) 阳性率分别为0.56％(402例)、1.48％(1 062例)、1.14％(821例)、0.09％(61例);初次献血者抗-HCV、HBsAg 、抗-TP及HIV(Ag/Ab)阳性率均高于多次献血者(P＜0.05);402例抗-HCV阳性无偿献血者中合并HBsAg、抗-TP、HIV(Ag/Ab) 阳性率分别为1.74%(7例)、4.98%(20例)、0.25%(1例)。结论 抗-HCV阳性献血者合并TP感染率显著高于抗-HCV阴性无偿献血者, HCV合并HBV、HIV感染率低。
目的 分析重症烧伤患者血培养标本中检测出念珠菌的临床分布，探究重症烧伤患者血流念珠菌感染的病原学特征。方法 选取2012—2023年在广州市红十字会医院住院治疗的重症烧伤患者血培养标本1 148份，分析分离出念珠菌的非重复患者病死率、菌种分布、同时送检的其他类型标本念珠菌培养结果及患者念珠菌血流感染的检出时间与季节分布、抗菌药物使用情况及对常用抗真菌药物的耐药情况。结果 1 148份血培养标本中77份检出真菌，阳性率为6.71%。检出念珠菌感染的非重复患者27例，其中近平滑念珠菌13例，构成比为48.15%、白念珠菌8株，构成比为29.63%。血与静脉导管培养均检出念珠菌的有22例（81.48%）；血与伤口分泌物培养圴检出念珠菌的有10例（37.04%）；血、静脉导管、伤口分泌物培养圴检出念珠菌的有4例（14.81%）。静脉导管检出念珠菌高于其他类型标本。27例重症烧伤患者血流感染检出念珠菌的时间主要分布在入院后第2~3周、季节主要分布在春夏季。近平滑念珠菌、白念珠菌、热带念珠菌对氟康唑敏感率分别为83.33%、87.50%和75.00%。结论 重症烧伤患者血流近平滑念珠菌检出率最高，发生血流感染时间主要在春夏季及烧伤入院后第2~3周，静脉导管留置是增加重症烧伤患者念珠菌血流感染的因素。我院念珠菌对抗真菌药物具有较高敏感性。
Objective To retrospective analyze the clinical distribution of Candida species detected in blood cultures of patients with severe burns and to investigate the etiological characteristics of Candida bloodstream infections in these patients．Methods A total of 1 148 blood culture specimens were collected from patients with severe burns hospitalized at an institution between 2012 and 2023．Patients data with Candida bloodstream infections isolated from 1 148 blood culture specimens were analyzed，including mortality rates，species distribution，Candida culture results from other simultaneously collected specimen types，and the timing and seasonal distribution of Candida bloodstream infections，the use of antibiotics and resistance to commonly-used antifungal drugs．Results A total of 1 148 blood culture samples，77 fungi were separated，resulting in a positive rate of 6.71%．Among the 27 patients with Candida infections，13 cases（48.15%）were caused by Candida parapsilosis and 8 cases（29.63%）by Candida albicans．Candida was isolated from both blood and intravenous catheter cultures in 22 cases，with a positivity rate of 81.48%．Candida was isolated from both blood and wound secretion cultures in 10 cases（positivity rate of 37.04%），and 4 cases from blood，intravenous catheter and wound secretion cultures（positivity rate of 14.81%）．The detection rate of Candidafrom intravenous catheters was higher than that from other specimen types．Candida bloodstream infections were most commonly observed during the 2nd and 3rd week after admission，with a seasonal peak in spring and summer．The susceptibility rates of Candida parapsilosis、Candida albicans and Candida tropicalis to fluconazole were 83.33%、87.50% and 75.00%，respectively．Conclusions The detection rate of Candida parapsilosis in bloodstream infections among patients with severe burns was the highest．These infections predominantly occur during the spring and summer and in the 2nd and 3rd week post-admission．The presence of intravenous catheters significantly contributes to Candida infections．The Candida in the hospital has high sensitivity to antifungal drugs．
