The Early Diagnostic Value Of G Test For Pneumocystis Carinii Pneumonia In Renal Transplant Recipients

Objective: To explore the early diagnostic value of G test for pneumocystis carinii pneumonia in renal transplant recipients,the plasma(1,3)-beta-D-glucosan content of PCP patients and non-pcp patients was compared and the sensitivity,specificity,positive predictive value and negative predictive value of G test were calculated.Methods:From Jan 2012 to Dec 2017,58 cases of renal transplant recipients treated in our hospita were enrolled as the research object,which were divided into comfirmed group,clinical diagnosis group and non-PCP group,the results of the first G test after admission were compared with patients in each group.The cut-off value for diagnosis of PCP were determined to be 10pg/ml,then analysis the sensitivity,specificity,positive predictive value as well as negative predictive value.Draw the receiver operating characteristic(ROC)curve and calculate the area under the curve as well as the best cut-off value by statistical software,then analysis the sensitivity,specificity,positive predictive value(PPV),negative predictive value(NPV)based on this cut-off value.Result:1,There was no statistically significant difference in baseline data(Gender,age)between the three groups,the measurement data of G test in each group were not in normal distribution..The median value of plasma BG concentration in the confirmed group was 99.05(30.64~938.80)pg/ml,the median value of plasma BG concentration in the clinical diagnosis group was 58.18(22.62~201.73)pg/ml,the median value of plasma BG concentration in the non-pcp group was 4.12(3.84~5.11)pg/ml.The level of plasma(1,3)-beta-D-glucosan in comfirmed group and clinical diagnosis group were significantly higher than that in non-PCP group(P<0.01),there was no significant difference in the level of(1,3)-beta-D-glucosan between the comfirmed group and the clinical diagnosis group(P>0.05).2,One of the 14 patients in the confirmed group was false negative,and 2 of the 19 patients in the clinical diagnosis group were false negative,and 4 of the 25 patients in the non-pcp group were false positive.The sensitivity,specificity,positive predictive value and negative predictive value of G test were 90.91%,84.00%,88.24%,87.50%.3,The area under the curve was 0.972(CI:0.937~1.000),and G test become more efficient with cutoff level 9.05 in this study,with this standard,the Se and Sp were 100.00% and 84.00%,the PPV and NPV were 89.19% and 100.00%.4,In the fourteen patients of confirmed group,the report time of G test positive results was 3.73 days earlier than that of pathologic examination.Among them,the oldest was fifteen days,and there are two laboratory tests returned the same day in two patients.Conclusion:1,G test has important clinical value in early diagnosis of pneumocystis pneumonia after kidney transplantation,which has high sensitivity.2,Proper reduction of the positive threshold of G test could increase the sensitivity of G test to the diagnosis of pneumocystis pneumonia after kidney transplantation.3,The G test had a better time advantage in the early diagnosis of renal transplantation than the pathologic examination,it may have positive significance for early anti-pcp treatment,delayed disease progression,and mortality risk reduction.4,The false positive of G test may be related to the application of cephalosporin antibiotics,however,there was no significant increase for G test in this case.5,The PCP should be highly suspected when renal transplant recipients developed fever,dry cough,dyspnea,and lung signs and chest CT in the three to five months after kidney transplantation.