格特隐球菌在河北地区引起1例脑膜炎的临床与实验研究

Clinical presentation and laboratory study for a case of cryptococcal meningitis caused by Cryptococcus gattii in Hebei province

目的报道1例我国河北地区由格特隐球菌引起的脑膜炎,并对该菌进行试验研究。方法将分离自患者脑脊液中的隐球菌分别接种于Chromagar显色培养基和刀豆氨酸-甘氨酸-溴麝香草酚蓝(CGB)培养基35℃培养,使用API 20C AUX、全自动微生物鉴定仪Vitek 2 Compact、生物梅里埃基质辅助激光解析电离飞行时间质谱分析(MALDI-TOF MS)、r DNA ITS和IGS序列分析等方法对该菌进行菌种鉴定,并使用ATB FUNGUS 3进行抗真菌药敏试验。结果该菌在显色培养基上35℃培养48 h后为白色略带粉色菌落,在CGB培养基35℃培养5 d后使CGB培养基由黄色变为蓝色。API 20C AUX、Vitek 2 Compact和MALDI-TOF MS的鉴定结果均为新生隐球菌,r DNA ITS和IGS序列分析均提示该菌为格特隐球菌。5-氟胞嘧啶、两性霉素B、氟康唑、伊曲康唑、伏立康唑对该菌的最小抑菌浓度分别是≤4μg/m L、≤0.5μg/m L、≤1μg/m L、≤0.125μg/m L、≤0.06μg/m L。结论 CGB培养基、r DNA ITS和IGS序列分析能够区分新生隐球菌和格特隐球菌,应重视格特隐球菌的分离鉴定。

Objective To report a case of meningitis caused by Cryptococcus gattii in North China and related laboratory investi-gation.Methods The strain isolated from the patient mentioned above was inoculated on the Chromagar media and Canavanine-gly-cine-bromthymol blue （CGB）media at 35℃.API 20C AUX、Vitek 2 Compact、Matrix-Assisted Laser Desorption Ionization-Time-of-Flight Mass Spectrometry （ MALDI-TOF MS）、ribosomal ITS and IGS sequence analysis were performed for identification. Antifungal susceptibility test was also performed with ATB FUNGUS 3.Results The color of the strain on the Chromagar media was colorless and slight pink.It turned the CGB media blue five days later.It was identified as Cryptococcus neoformans by API 20C AUX、Vitek 2 Compact and MALDI-TOF MS.It was considered as Cryptococcus gattii by sequence analysis of genes of ribosomal ITS and IGS.The minimal inhibitory concentrations of 5-Flucytosine、AmphotericinB、Fluconazole、Voriconazole、Itriconazole against the isolate were≤4μg/mL、≤0.5μg/mL、≤1μg/mL、≤0.125μg/mL、≤0.06μg/mL respectively.Conclusions CGB media、ribosomal ITS and IGS sequence analysis can discriminate Cryptococcus gattii from Cryptococcus neoformans . CGB is an easy method to identify C.gattii . I-solation and identification of C.gattii need to be paid more attention.