Clinical Features,Strain Genotype And Their Correlation Of Cryptococcal Meningitis In AIDS Patients

BackgroundCryptococcal disease is an aggressive fungal disease mainly caused by Cryptococcal neoformans(CN),which is one of the main opportunistic infections in human immunodeficiency virus(HIV)infections and AIDS patients.Cryptococcal meningitis(CM)is the most common form of cryptococcal disease.HIV-negative CM has a variety of clinical manifestations,usually chronic onset,mainly manifested as fever,headache,nausea,vomiting and blurred vision and other symptoms,may have positive signs of meningeal irritation,and severe cases can appear consciousness disorders,cerebral herniation and other life-threatening conditions.There was no significant difference in clinical symptoms of AIDS with CM compared with HIV-negative CM,but its duration was longer and less atypical.Studies have found that impaired consciousness,increased intracranial pressure,decreased blood cholinesterase levels,decreased albumin levels,and high serum HIV RNA quantification levels are independent risk factors for the poor prognosis of AIDS and CM.Without early diagnose and effectively treatement,the fatality rate of CM is extremely high.Cryptococcus neoformans(VN)and Cryptococcus gattii(VG),and their genotypes can be divided into VNI,VNII,VNIII,VNIV,VNB,VGI,VGII,VGIII and VGIV.Among them,the global trend is mainly VNI-type popularity.Cryptococcal genotypes have been found to be associated with clinical symptoms,antifungal susceptibility,and prognosis.In HIV-negative people,VNI is more likely to have central nervous system infections,with vomiting and increased intracranial pressure more pronounced.VNB is associated with higher mortality.The sensitivity of VNI to in vitro antifungals of Amphotericin B(AMB)was significantly higher than that of VNII,and the sensitivity of VGII to fluconazole in vitro antifungals was significantly higher than that of other genotypes.However,there are few studies on AIDS combined with CM Cryptococcus genotype,and reports of its genotype and clinical features are even rarer.Content and purpose of the studyTo understand the clinical features of CM in AIDS patients(clinical symptoms,cerebrospinal fluid examination,in vitro antifungal drug sensitivity,etc.),multi-site sequence typing technology(MLST)to identify the genotype of Cryptococcus generos,and compare the relationship between different genotypes and clinical features of Cryptococcus CM in AIDS patients,in order to provide a more scientific basis for the treatment of CM in AIDS patients.Research objects and methods1.Clinical features of cryptococcal meningitis in AIDS patients1.1 Study subjects:102 HIV-positive CM patients admitted to the Infectious Disease Center of the Eighth Affiliated Hospital of Guangzhou Medical University,and 19 HIV-negative CM patients admitted during the same period were used as controls.1.2 Detection method:The method of ATB FUNGUS 3 was used to determine the sensitivity of each clinical strain of Cryptococcus to 5 commonly used antifungal drugs(5-FC、AMB、FCA、ITR、VRC)in vitro.1.3 Follow-up points,observation indicators and endpoints:Follow-up points included baseline and 4 weeks,12 weeks,24 weeks and 48 weeks after admission.Observation index:clinical features of CM patients.Primary Observational Endpoint:24 w after diagnosis of CM or at death,Secondary Endpoint:4 w after CM diagnosis.2.Comparison of genotype and clinical features of cryptococcal meningitis strains in AIDS patients2.1Study subjects:121 strains of Cryptococcus bacteria isolated and cultured and well preserved by cerebrospinal fluid were isolated from the above 102 patients of CM in AIDS patients and 19 patients of HIV-negative CM.2.2 Detection method:The internationally recognized multi-locus sequence typing technique(MLST)was used as the clinical strain typing method of Cryptococcus,and seven housekeeping genes(CAP59,GPD1,LAC1,PLB1,SOD1,URA5 and IGS1)were analyzed to identify each Cryptococcus clinical strain to the genotype level.3.Statistical method:SPSS 26.0 statistical software is used for data analysis,andc~2tests and Fisher exact probability method are used for counting data,expressed as absolute numbers and percentages;The measureds were measured using either an independent sample t-test or the Mann-Whitney U test,expressed as mean plus or minus standard deviation or median and interquartile ranges.The factors P<0.05 or0.10 in the results of univariate logistic regression analysis were excluded by collinearity diagnosis and multivariate loginess,and then included in binary logistic or multivariate logistic regression model for multivariate analysis,and the risk factors were described by odds ratio(OR)and 95%confidential intervals(95%CI).All statistical tests are two-sided and are considered statistically significant with P<0.05.Result1.Clinical features of cryptococcal meningitis in AIDS patientsCompared with 19 HIV-negative CM patients,the time from neurological symptoms to clinical diagnosis was shorter,encephalitis was lower,cerebrospinal fluid biochemical white blood cell number,protein content and Pane’s globulin test positive rate were lower,cerebrospinal fluid glucose content was higher,the proportion of abnormal results in head imaging was lower,and the sensitivity to in vitro antifungal drugs of amphotericin B was higher(P<0.05).The results of multivariate logistic regression analysis in the survival group and death group of patients with AIDS and CM showed that baseline consciousness impairment and fluconazole insensitivity were independent risk factors for death at4w and 24w(P<0.05).2.Comparison of genotype and clinical features of cryptococcal meningitis strains in AIDS patientsThe 102 clinical strains of Cryptococcus neoformans in HIV-positive CM patients were all Cryptococcus neoformans,and their genotypes were VNI 99,VNII 1and VG 2.Cryptococcus neoformans(VN)sequence types were divided into ST5 83(83.0%),ST4 5(5.0%),ST31 3(3.0%),ST43 1(1.0%),ST93 4(4.0%),ST395 1(1.0%),and possibly new STx 3(3.0%).3.There was no significant difference between the 83 ST5 sequence type of cryptococcal meningitis strains in AIDS patients and the 17 non-ST5 sequence types(clinical symptoms,cerebrospinal fluid examination,in vitro antifungal drug sensitivity,etc.)in HIV-positive CM patients(P>0.05).Conclusion1.The clinical features of CM in AIDS patients are mainly fever,headache,nausea and vomiting,and the inflammatory response of cerebrospinal fluid is less severe than that of HIV-negative CM.Baseline impaired consciousness and fluconazole insensitivity are independent risk factors for death at 4w and 24w of CM in AIDS patients2.The CM in AIDS patients is mainly Cryptococcus neoformans,and the MLST classification VNI(ST5)genotype accounts for the vast majority.Clinical features are similar across genotypes.