Hasbek Mürşit, Fırtına Topçu Kübra, Özüm Ünal
Sivas Cumhuriyet University Faculty of Medicine, Department of Medical Microbiology, Sivas, Turkey.
Sivas Cumhuriyet University Faculty of Medicine, Department of Neurosurgery, Sivas, Turkey.
Mikrobiyol Bul. 2019 Jul;53(3):343-347. doi: 10.5578/mb.68131.
Globicatella sanguinis is catalase-negative, alpha-hemolytic, nonmotile, facultative anaerobic grampositive cocci, identified as a new species in 1992. Since the colony morphology in blood agar and microscopic appearance resembles streptococci, it is thought that some of the isolates previously identified in the Streptococcus viridans group were G.sanguinis species. G.sanguinis has been isolated from various clinical specimens, its species identification and antibiotic susceptibility have been tested since the year it was identified. Clinical specimens in which it is isolated include various mucosal surfaces, blood, urine, wound and cerebrospinal fluid. In this report, considering also the literature information, a case of G.sanguinis which is thought to cause meningitis was presented. Our case is a 39-year-old female patient with a lumboperitoneal shunt. The patient was admitted to the neurosurgery clinic with a headache and vision loss and was hospitalized in the service with a pre-diagnosis of pseudotumor cerebri. Neurological examination revealed no pathological findings. Eye examination revealed mild papillary edema, local retinal hemorrhage, and bilateral expansion in retinal vascularization. There was no pathologic findings in the brain magnetic resonance imaging. The colonies resembling alpha hemolytic streptococci were isolated from the cerebrospinal fluid taken upon the development of neck stiffness, fever, and tachycardia on the 10th day of hospitalization of the lumbo-peritoneal shunt administered patient. The identification of the isolate was determined in Bruker IVD MALDI Biotyper 2.3 (Bruker Daltonik GmbH, Bremen, Germany), available in our laboratory and it was identified as G.sanguinis (KJ680157.1) with a score of > 2. The definite identification of the isolate at the species level was made by 16S rDNA sequence analysis and it was determined that the bacterium was G.sanguinis with 100% similarity and coverage. The minimum inhibitory concentration (MIC) for some of the antibiotics was determined by the agar gradient method. The MIC values were found as; linezolid 0.50 µg/ml, vancomycin 0.75 µg/ ml, imipenem 0.75 µg/ml, meropenem 3 µg/ml, penicillin G 6 µg/ml and cefotaxime > 32 µg/ml. It is known that these rare isolates can be isolated in greater numbers along with the introduction of MALDITOF MS-based devices in many laboratories. Following greater numbers of isolation of this rare species of bacteria, our knowledge about its clinical significance, placement in the flora and antibiotic susceptibility will also be expanded.
血源环球菌是过氧化氢酶阴性、α溶血、无动力、兼性厌氧的革兰氏阳性球菌,于1992年被鉴定为一个新物种。由于其在血琼脂中的菌落形态和显微镜下外观与链球菌相似,人们认为先前在草绿色链球菌群中鉴定出的一些分离株实际上是血源环球菌。血源环球菌已从各种临床标本中分离出来,自其被鉴定以来,一直在检测其菌种鉴定和抗生素敏感性。分离出该菌的临床标本包括各种黏膜表面、血液、尿液、伤口和脑脊液。在本报告中,结合文献信息,介绍了一例被认为由血源环球菌引起脑膜炎的病例。我们的病例是一名39岁的女性患者,有腰大池腹腔分流术史。该患者因头痛和视力丧失入住神经外科门诊,初步诊断为假性脑瘤并住院治疗。神经学检查未发现病理结果。眼科检查发现轻度视乳头水肿、局部视网膜出血以及视网膜血管双侧扩张。脑磁共振成像未发现病理结果。在接受腰大池腹腔分流术的患者住院第10天,出现颈部僵硬、发热和心动过速后,从采集的脑脊液中分离出了类似α溶血链球菌的菌落。使用我们实验室现有的布鲁克IVD MALDI Biotyper 质谱仪(德国不来梅的布鲁克道尔顿公司)对分离株进行鉴定,鉴定结果为血源环球菌(KJ680157.1),得分>2。通过16S rDNA 序列分析在物种水平上对分离株进行了明确鉴定,确定该细菌为血源环球菌,相似度和覆盖率均为100%。采用琼脂梯度法测定了部分抗生素的最低抑菌浓度(MIC)。MIC 值如下:利奈唑胺0.50 µg/ml、万古霉素0.75 µg/ml、亚胺培南0.75 µg/ml、美罗培南3 µg/ml、青霉素G 6 µg/ml 和头孢噻肟>32 µg/ml。众所周知,随着许多实验室引入基于MALDITOF MS 的设备,这些罕见的分离株可能会被更多地分离出来。在更多地分离出这种罕见细菌后,我们对其临床意义以及它在菌群中的地位和抗生素敏感性的了解也将得到扩展。