To investigate the charicteristics of clinic and pathogen of crytococcal meningoencephalitis caused by Cryptococcus gattii and to provide assistance for clinical diagnosis and therapy.

The clinical data, laboratory examination, diagnosis and treatment were analyzed, respectively, and the isolation and identification of pathogenic fungus, antimicrobial susceptibility testing and 18S rRNA sequence were determined to the isolate.

The patient had a history of long-term chronic hepatitis and immunodeficiency. Clinical manifestations were strenuous headache, high fever and vomiting. Brain imaging showed that parenchymal was damaged. The detection results of cerebrospinal fluid showed that CSF pressure, the white blood cell count, and protein increased significantly, but the glucose and chloride reduced. The ink staining result of CSF was positive. The isolate of CSF in Chromogenic medium was white colonies and Canavanine-glycine-bromthymol blue (CGB) medium showed blue. The isolate was identified as cryptococcus neoformans by Vitek-2 Compact, which was identified as Cryptococcus gattii by 18S rRNA sequencing (similarity > 99%) and phylogenetic analysis. Drug susceptibility results showed that Cryptococcus gattii was sensitive tothe 5-fluorouracil, amphotericin B, fluconazole, itraconazole and voriconazole. Patients symptoms and signs improved after combined application of fluconazole, amphotericin B and 5-fluorouracil.

Molecular method for identification of Cryptococcus gattii was rapid and accurate. Early pathogenic diagnosis, early combined treatment with amphotericin B and 5-fluorouracil, sufficient and full course of treatment are the key for treatment of crytococcal meningoencephalitis.