The Clinical Value Of G Test/GM Test Of Bronchoalveolar Lavage Fluid In The Diagnosis Of Invasive Pulmonary Fungal Infecttion

Objective:To investigate the detection of(1,3)-β-D glucan(1,3-β-D-glucan)antigen(G test)and galactomannan in bronchoalveolar lavage fluid(BALF)Galactomannan)Antigen detection(GM test)for the diagnostic value of Invasive pulmonary fungal infections(IPFI).Methods:Thirty children who were hospitalized in the Department of Pediatrics,Minhang Hospital of Hubei University for Nationalities from January 2016 to December 2018 were enrolled in the children with invasive pulmonary fungal infection(IPFI group).The 30 patients were randomly selected at the time of admission or during hospitalization.Children who were diagnosed but excluded IPFI before discharge(non-IPFI group),collected general information,drug treatment and disease outcomes,clinical symptoms,signs,imaging features,qualified specimens(sputum,blood,Bronchoalveolar lavage fluid and other specimens)fungal microscopy and culture results,blood routine and C-reactive protein(CRP)results,serum and bronchoalveolar lavage fluid G and GM test results,all data were recorded,organized and analyzed To calculate the sensitivity,specificity,positive predictive value,negative predictive value,etc.of serum and bronchoalveolar lavage fluid G and/or GM test(parallel experiment),and draw the receiver operating characteristic curve of each parallel experiment(receiver operating Characteristic,ROC)curve,and calculate the area under the curve(AUC),compare the diagnostic value of each experiment for IPFI.Results:1.From January 2016 to December 2018,a total of 60 children met the inclusion criteria,30 in the IPFI group and 30 in the non-IPFI group.There were no statistically significant differences in age,height,weight,length of hospital stay,and gender between the two groups.2.Thirty patients with IPFI who were eligible for bronchoalveolar lavage were positive for fungal culture(4 cases of Candida albicans and Candida glabrata,3 cases of Aspergillus,1 case of Pneumocystis),blood Fungal culture was positive in 14 cases(5 cases of Candida albicans,4 cases of Aspergillus,3 cases of Candida glabrata,1case of Candida albicans near Candida),including bronchoalveolar lavage fluid and 1case of blood culture was positive(both Candida glabrata),3 cases of cysts of Pneumocystis were found in qualified sputum samples,and the same hyphae were found by multiple microscopy and 2 cases of fungal culture were positive(Candida albicans)bacteria).Among all the specimens,the number of Candida species was the highest,accounting for 19 cases,followed by 7 cases of Aspergillus and 4 cases of Pneumocystis.3.There was no statistically significant difference between the IPFI group and the non-IPFI group in the combined use of broad-spectrum antibiotics for 2 weeks,secondary neutropenia,and invasive procedures.The difference in risk factors between weeks,leukemia and exposure to fungal environment was statistically significant.The IPFI group had a longer hospital stay than the non-IPFI group,had more underlying diseases with leukemia,and had a higher probability of exposure to the fungal environment than the latter.Be high.4.The clinical symptoms and signs of pulmonary fungal infection in the two groups showed that there was a statistically significant difference in blood between the IPFI group and the non-IPFI group(P<0.05).There was no significant difference in the incidence of cough,cough,fever,wheezing,dyspnea,and auscultation of the lungs(P>0.05).5.30 children in the IPFI group were treated with standardized antifungal therapy,30 cases were effective(25 cases cured,5 cases improved).Among them,13 cases were cured with fluconazole,3 cases were improved,10 cases were cured by voriconazole,2 cases were improved,and 2 cases were cured by caspofungin.6.The chest CT imaging of 30 children in the IPFI group was most common with pleural effusion,followed by lung consolidation,pleural thickening,thickening of the bronchial walldiffuse miliary shadow,ground glass shadow and interstitial lung.Sexual lesions.7.The number of white blood cells and the percentage of neutrophils in the IPFI group were higher than those in the control group,and the difference was statistically significant(P<0.001).There was no significant difference in CRP between the two groups(P>0.05).8.Among the 30 patients in the IPFI group,20 were positive for BALF G,10were negative,12 were positive for serum G test,and 18 were negative.The results of the two specimens G test were compared with aχ~2value of 4.286 and a P value of0.038.Among the 60 patients in the IPFI group and the non-IPFI group,the sensitivity of the BALF G and/or GM test(parallel test)for the diagnosis of IPFI was 73.3%,the specificity was 86.7%,the positive predictive value was 84.6%,and the negative predictive value was 76.5.%,and according to the results,the misdiagnosis rate was13.3%%,the missed diagnosis rate was 26.7%,and the Youden index was 60.0%.The sensitivity of the above experimental diagnosis of IPFI was 53.3%,the specificity was80.0%,the positive predictive value was 72.7%,the negative predictive value was63.2%,and the misdiagnosis rate was 20.0%,the missed diagnosis rate was 46.7%,and the Youden index was calculated according to the results.33.4%.Conclusion:1.Long-term use of broad-spectrum antibiotics is one of the more common high-risk factors in children with IPFI.The basic disease with leukemia and the clear history of contact with fungal environment are the warning signs of the disease.It is necessary to be alert to the possibility of IPFI.2.The clinical signs,symptoms and imaging features of children with IPFI are lack of specificity,so it is difficult to distinguish them from common pulmonary infectious diseases.3.Clinically,children with IPFI have a better therapeutic effect.The antifungal drugs commonly used in our department are fluconazole and voriconazole,and caspofungin is relatively less used.4.When the BALF G test is compared with the serum G test,the positive rate of the former is higher than that of the latter.The sensitivity,specificity,positive predictive value and negative predictive value of the tracheal alveolar lavage G test and/or GM parallel test were higher than the serum,and the area under the ROC curve of the BALF experiment was larger than the area under the ROC curve of the serum test.The former’s misdiagnosis rate and missed diagnosis rate are lower than the latter,That is to say,the combined detection of(1,3)-β-D glucan and galactomannan antigen in BALF is more accurate and valuable for the diagnosis of invasive pulmonary fungal infection,and has a certain clinical application value.