Lau Susanna K P, Woo Patrick C Y, Woo Gibson K S, Yuen Kwok-Yung
Department of Microbiology, The University of Hong Kong. HKU-Pasteur Research Centre, Hong Kong.
J Clin Microbiol. 2002 Jul;40(7):2681-5. doi: 10.1128/JCM.40.7.2681-2685.2002.
We describe the application of 16S rRNA gene sequencing in defining two cases of catheter-related Microbacterium bacteremia. In the first case, a gram-positive bacillus was isolated from both the blood culture and central catheter tip of a 39-year-old woman with chronic myeloid leukemia. The API Coryne system identified the isolate as 98.9% Aureobacterium or Corynebacterium aquaticum. In the second case, a gram-positive bacillus was recovered from five sets of blood cultures from both central catheter and percutaneous venipuncture of a 5-year-old girl with acute myeloid leukemia. The isolate was identified by the API Coryne system as 99.7% Cellulomonas or Microbacterium species. Further phenotypic tests failed to identify the two isolates. 16S rRNA gene sequencing showed 99.4% similarity between the first isolate and Microbacterium oxydans and 98.7% similarity between the second isolate and Microbacterium trichotecenolyticum, indicating that both isolates were Microbacterium species. Microbacterium infections are rarely reported in the literature. Although the central venous catheter was previously proposed to be a source of bacteremia, the first case in this report represents the first culture-documented case of catheter-related Microbacterium bacteremia.
我们描述了16S rRNA基因测序在确诊两例导管相关微小杆菌血症病例中的应用。在第一例中，从一名患有慢性髓性白血病的39岁女性的血培养物和中心导管尖端均分离出一株革兰氏阳性杆菌。API棒状杆菌系统鉴定该分离株为98.9%的水生金色杆菌或水生棒状杆菌。在第二例中，从一名患有急性髓性白血病的5岁女孩的中心导管和经皮静脉穿刺采集的五组血培养物中均分离出一株革兰氏阳性杆菌。API棒状杆菌系统将该分离株鉴定为99.7%的纤维单胞菌或微小杆菌属菌种。进一步的表型试验未能鉴定出这两种分离株。16S rRNA基因测序显示，第一株分离株与氧化微小杆菌的相似度为99.4%，第二株分离株与解木霉素微小杆菌的相似度为98.7%，表明这两种分离株均为微小杆菌属菌种。微小杆菌感染在文献中鲜有报道。尽管先前有人提出中心静脉导管是菌血症的一个来源，但本报告中的第一例代表了首例经培养证实的导管相关微小杆菌血症病例。
