Identification and antibiotics sensitivity analysis of Herbaspirillum huttiense in catheter-related bloodstream infection / 中华检验医学杂志

ABSTRACT

Objective:To analyze the identification and antibiotics susceptibility of Herbaspirillum in catheter-related bloodstream infection, and improve the awareness and attention of the rare pathogenic microorganisms for clinicians and microbiologists. Methods:The bacterium was isolated from a positive blood culture of a hemodialysis patient with chronic renal failure. The smear of isolate was prepared, stained and observed by microscope. The single colonies were identified by mass spectrometry and VITEK 2 Compact identification and antibiotics sensitivity analysis system, respectively. Then, 16S ribosomal DNA (rDNA) was amplified and sequenced, and bacterial genome was sequenced.Results:The gram-negative bacilli was found in the positive blood culture bottle. After incubated on blood agar for 16 hours, milky white, bulging and non-haemolytic colonies were observed. The identification result was Burkholderia cepacian by VITEK 2_Compact and antimicrobial susceptibility testing showed resistance to aztreonam and polymyxin but sensitive to other drugs in N335 card. The isolate could not be identified by VITEK MS with clinical database. However, it was identified as Herbaspirillum huttiense/Herbaspirillum aquaticum with research database. The 16S rDNA of the strain was consistent with Herbaspirillum huttiense and Herbaspirillum aquaticum (more than 99%). High-throughput bacterial genome sequencing revealed that the isolate in this case shared 100% homology with Herbaspirillum huttiense subsp putei IAM 15032 in Genbank database, which confirmed that the isolate was Herbaspirillum huttiense. Conclusions:There are more and more environmental microorganisms evolved into human pathogenic bacteria. Herbaspirillum species are easy to be misidentified because its biochemical characteristics are similar to other strains.