Diagnosis Of Pneumocystis Pneumonia By Metagenomic Next-generation Sequencing In The Peripheral Blood Of Patients With Kidney Disease

Background and Aims:Pneumocystis jirovecii is an opportunistic infectious pathogen that can cause pneumocystis pneumonia(PCP)in HIV patients.The kidney transplant recipients and patients with kidney diseases receive immunosuppressive therapy.PCP is not uncommon in such patients,but early etiological diagnosis is difficult.Metagenomic next-generation sequencing(mNGS)has higher sensitivity for pathogen identification in a variety of infections.In this study,mNGS was used to detect the peripheral blood samples of Kidney disease patients complicated with PCP,and to evaluate the diagnostic performance of mNGS in the peripheral blood for the etiology of PCP.Methods:From August 2018 to December 2019,We collected 36 cases with kidney disease complicated with pneumonia and clinically diagnosed with PCP after receiving immunosuppressive therapy.mNGS was used to analyze the pathogen types and sequences in peripheral blood samples to evaluate the detection efficiency to PCP.To compare the efficacy of mNGS and traditional clinical diagnosis(fungal G combined with lactate dehydrogenase detection)of PCP.In addition,patients with Bacterial,fungal,or viral pneumonia were established as positive controls.Results:36 peripheral blood samples were collected from 37 patients,and results for all samples were obtained within 72 hours.Pneumocystis jirovecii was detected by mNGS in 35 of the 37 samples,with a sensitivity of 94.59%,specificity of 100%.Sequences of other pathogens were detected in 31 patients.Cytomegalovirus(CMV)was detected in 19 of the 37 cases,Epstein-Barr virus(EBV)detected in 6 cases,herpes simplex virus(HSV)detected in 5 cases,and torque teno virus detected in 7 cases.Bacterial sequences were detected in 8 patients,including 2 cases of Staphylococcus,2 cases of Acinetobacter,1 case of Escherichia coli,1 case of Klebsiella pneumoniae,and 4 cases of uncommon bacteria.There were 33 patients with positive fungal G test and elevated lactate dehydrogenase(BG/LDH),and 4 patients with multiple negative fungal G test.The sensitivity of BG/LDH was 89.19%,the specificity 56.0%.Conclusion:mNGS has obvious advantages over the traditional method of diagnosing PCP.It has the characteristics of accuracy,simplicity and noninvasiveness,and is of great value for the early diagnosis of PCP.