Abstract:Objective To compare the value of 16S rDNA sequencing and traditional culture in the detection of pathogens in liver and renal abscess, analyze characteristics and composition of pathogens in liver and renal abscess. Methods Abscess drainage fluid of 32 patients (24 cases of liver abscess and 8 cases of renal abscess) who underwent percutaneous drainage in a hospital from December 2019 to December 2020 were collected, pathogens were identified by traditional culture and 16S rDNA sequencing, flora characteristics of liver and renal abscess were compared and analyzed. Results The traditional culture results of abscess drainage fluid were 26 cases (81.25%) positive and 6 cases (18.75%) negative (including 3 cases of liver abscess and 3 cases of renal abscess), while the positive rate of 16S rDNA sequencing was 100%. The abundance of microbial flora in liver and renal abscess groups was similar, but the stacked bar chart and principal component analysis (PCA) indicated significant differences in the composition of pathogens between two groups. Linear discriminant analysis (LDA) showed that the flora of liver abscess group was mainly characterized by Deltaproteobacteria, Enterobacterales, Enterobacteriaceae and Klebsiella spp.; the flora of renal abscess group was mainly characterized by Comamonadaceae, Mycobacteriaceae, Proteus spp., Brevibacillus spp., Cellulosilyticum spp., Lachnospira spp., Leptotrichia spp., Pelomonas spp., Mycobacterium spp., Thermicanus spp. and Saccharimonadaceae spp.. Conclusion 16S rDNA sequencing is superior to traditional culture in the detection of pathogens in liver and renal abscess, there are significant differences in the composition of pathogens between liver and renal abscess, 16S rDNA sequencing is an effective method to deeply understand the characteristics of pathogens in liver and renal abscess.

Abstract:Objective To explore the feasibility and practicability of metagenomic next-generation sequencing (mNGS) technique in rapid identification of infection sources in hospital-associated cluster infection events. Methods Pharyngeal, anal swabs and blood specimens of 6 neonates with fever and diarrhea (or rash), as well as specimens (pharyngeal and anal swabs) of other neonates and health care workers (HCWs) in the same neonatal center of a hospital during the same period and environmental specimens were collected, traditional culture method, enterovirus universal polymerase chain reaction (PCR), mNGS and Echovirus 18 (ECO18) specific PCR were adopted for detection. Results No pathogen was found in the bacterial culture of 6 neonates' blood, anal and pharyngeal swabs, enterovirus universal PCR and ECO18 specific PCR were both positive for anal swabs. At least one specimen from different specimens of 6 neonates was found ECO18 by mNGS, positive rates from high to low were anal swabs (66.66%), blood (50.00%) and pharyngeal swabs (0). The pharyngeal and anal swab specimens of 18 asymptomatic neonates in the same ward during the same period were detected by mNGS, anal swab specimens of 2 cases were positive for ECO18, HCWs and environmental specimens didn't found ECO18 or other enterovirus. Conclusion mNGS can detect low copy number of ECO18 in feces or serum of patients infected with ECO18, it is an effective auxiliary method for the diagnosis of enterovirus infection, and has the potential to trace the pathogen of hospital cluster enterovirus infection.

Abstract:Objective To explore whether HIV-1 provirus DNA in peripheral blood of patients with HIV-1 low viral load (LVL) carries dominant drug-resistant mutations (DRMs), and the potential clinical significance of HIV-1 provirus DNA resistance detection. Methods The whole blood specimens of HIV-1 infected persons who received antiviral treatment in the outpatient department of a hospital for more than 6 months and plasma viral load (VL) of HIV-1 RNA was 50-1 000 copies/mL in two consecutive DNA genotype resistance detection between May 2020 and May 2021 were collected, HIV-1 pol gene was amplified by nested polymerase chain reaction (PCR) and Sanger sequencing, the sequence information was analyzed by Stanford University HIV resistance database. Results The dominant DRMs of HIV-1 provirus DNA in 26 LVL specimens with known pol region sequence were analyzed. It was found that 7 cases of HIV-1 provirus DNA carried dominant DRMs, including 1 case (3.85%) with nucleoside reverse transcriptase inhibitor (NRTIs) dominant DRMs, 4 cases (15.38%) with non-nucleoside reverse transcriptase inhibitor (NNRTIs) dominant DRMs, 1 case (3.85%) with protease inhibitor (PIs) dominant DRMs and 1 case with integrase inhibitor dominant DRMs. A total of 3 cases showed low to moderate drug resistance, 1 of which had low resistance to drugs in the current antiviral treatment scheme, and the rest were potentially drug-resistant. Conclusion There are dominant DRMs in peripheral blood HIV-1 provirus DNA of patients with HIV-1 LVL, suggesting that the detection of DNA resistance of HIV-1 provirus can provide certain reference for the formulation and adjustment of AIDS treatment scheme.

Abstract:Objective To understand the disease characteristics and treatment of a pregnant COVID -19 woman who gave birth to triplets, as well as delivery outcome of triplets. Methods Clinical data, diagnosis and treatment process of the first pregnant COVID -19 woman who gave birth to triplets in China, as well as accompany delivery, monitoring methods and outcomes of premature infants were analyzed. Results One woman who was 28-week pregnancy and with 13-hour severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleic acid positive was admitted in a hospital, persistent high fever and dyspnea occurred during disease course. Convalescent plasma (CP) of COVID -19 patient and methylprednisolone were given, condition improved after timely treatment of relevant symptoms. At 32⁺⁵ weeks of gestation, cesarean section was performed due to severe intrahepatic cholestasis in pregnancy (ICP), as well as three chorionic villus and three amniotic cavity (the fetuses were in head, hip and transverse position respectively). Patient was discharged after two consecutive negative test result of SARS-CoV-2 nucleic acid. Each premature infant delivered by caesarean section was individually transported to a single neonatal intensive care unit by the neonatal escort transport team (wearing secondary protective clothing) for isolated treatment. During hospitalization, SARS-CoV-2 nucleic acid and SARS-CoV-2 IgM test were both negative; SARS-CoV-2 IgG test was positive, value gradually decreased. Pregnant woman and three premature infants were treated suc-cessfully and reached the discharge standard. Conclusion Convalescent plasma and methylprednisolone are effective for the treatment of COVID -19 pregnant woman with triplets, timely treatment of anemia, anxiety, insomnia and other related symptoms is helpful for the treatment of pregnant woman with triplets. The progress of ICP in pregnant COVID -19 woman with triplets is fast, and delivery is an effective treatment. Three premature infants by cesarean section of COVOD-19 pregnant woman did not have intrauterine vertical transmission.

Abstract:Objective To investigate the clinical characteristics of COVID -19 complicated with Pneumocystis pneumonia (PCP). Methods Medical record of a patient with PCP confirmed by pathological examination of bronchoalveolar lavage fluid during convalescence period of COVID -19 were analyzed, the relevant literatures were searched and reviewed. Results A total of 99 literatures were retrieved, 19 of which were case reports of COVID -19 combined with PCP. COVID -19 combined with PCP mostly occurred in critically ill patients with T-cell immunosuppression, and PCP occurred in 2 convalescent patients. Most clinical manifestations were fever, dry cough and dyspnea in varying degrees, laboratory examination showed elevation of serum 1, 3-β-D-glucan, chest imaging showed multi-lobe ground-glass infiltration, small reticular changes, consolidation, cyst-like lesions and pneumothorax. It was difficult for CT to distinguish whether COVID -19 was complicated with PCP, combined with sputum/bronchoalveolar lavage fluid Grocott's silver staining, immunofluorescence microscopy, polymerase chain reaction and serum 1, 3-β-D-glucan, the accuracy of Pneumocystis detection could be effectively improved. Compound sulfamethoxazole (TMP/SMZ) was the first choice for the treatment of PCP, dapsone, clindamycin and capofungin also had effective clinical efficacy. Conclusion Patients with severe COVID -19 and their convalescence period are at risk of PCP, but early identification is difficult. TMP/SMZ is the first choice for PCP treatment, combination therapy with dapsone, clindamycin and caspofungin can also be adopted.

Abstract:Objective To evaluate the regulatory effect of recombinant human interferon α1b(rhIFN-α1b)on immune function of children with infectious mononucleosis (IM) through regulating the expression of Foxp3. Methods 98 children with IM treated in the department of pediatrics of a hospital from March 2019 to March 2020 were randomly divided into interferon group (n=49) and ganciclovir group (n=49) by simple randomized number table method. Interferon group received rhIFN-α1b atomization inhalation treatment, ganciclovir group received ganciclovir intravenous drip, treatment courses were both 7 days. Clinical efficacy and safety of two groups of children were observed, expression level of Foxp3 mRNA in peripheral blood mononuclear cells (PBMC), immune function and serum-related cytokines of two groups of children before and after treatment were compared. Results The total effective rate and negative conversion rate of serum EB virus DNA (EBV-DNA) in interferon group were both higher than those in ganciclovir group (87.8% [43/49] vs 71.4% [35/49], 89.8% [44/49] vs 73.5% [36/49]; both P < 0.05). Compared with ganciclovir group, children in interferon group had shorter time of heat course and pharyngitis, shorter recovery time of abnormal laboratory indexes (leukocyte count, proportion of hetero-lymphocytes, ala-nine aminotransferase [ALT], creatine kinase isoenzyme MB [CK-MB]), and shorter hospitalization time (all P < 0.05). The Levels of peripheral blood CD3⁺ and CD8⁺, as well as serum tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in both groups of patients after treatment decreased compared with those before treatment (all P < 0.05), the values of CD4⁺ and CD4⁺/CD8⁺ in peripheral blood, expression level of Foxp3 mRNA in PBMC, as well as concentrations of serum immunoglobulin A(IgA), IgG and interleukin-2(IL-2) in both groups were all hi-gher than those before treatment (all P < 0.05); however, the improvement was more obvious in interferon group (all P < 0.05). The adverse reaction rate of interferon group was lower than that of control group (4.1% vs 20.4%, P < 0.05). Conclusion rhIFN- α1b may correct the abnormal cellular immune function of children with IM and improve their humoral immune level by up-regulating the expression level of Foxp3 mRNA in PBMC.

Abstract:Objective To evaluate the pathogenic characteristics and risk factors of multidrug-resistant organism (MDRO) infection after Stanford type A aortic dissection (TAAD). Methods Medical data of TAAD patients in a thoracic hospital from January 2019 to December 2020 were retrospectively analyzed, patients with MDRO infection after operation were selected as case group, case-control matching was conducted according to 1∶3 matching, the influencing factors of MDRO infection were analyzed by univariate and multivariate logistic regression. Results A total of 578 patients with TAAD were investigated, 34 of whom developed MDRO infection after operation. The main pathogens were Klebsiella pneumoniae (28 strains, 47.46%), Acinetobacter baumannii (16 strains, 27.12%) and Pseudomonas aeruginosa (8 strains, 13.56%). 105 non-infection cases were matched in control group. Univariate analysis showed that the duration of operation, length of stay in intensive care unit (ICU), duration of invasive ventilation, constituent ratio of continuous renal replacement therapy and duration of post-operative enteral nutrition in case group were all higher than those in control group; the amount of blood transfusion (red blood cells, platelets and plasma) in case group were all higher than control group; differences were all significant (all P < 0.05). Multivariate analysis showed that the length of stay in ICU (OR=1.071), duration of invasive ventilation (OR=1.013) and continuous renal replacement therapy (OR=6.739) were independent risk factors for MDRO infection after TAAD operation (all P < 0.05). Conclusion MDRO infection after TAAD operation is mainly Gram-negative bacterial infection, duration of invasive ventilation in patients should be shortened to ensure renal blood supply, timely and effective renal replacement therapy should be considered to reduce complications, shortening the length of stay in ICU can reduce the risk of MDRO infection after operation.

Abstract:Objective To analyze the characteristics of cardiovascular lesion caused by Mycoplasma pneumoniae (MP) infection in children with Kawasaki disease (KD), and provide guidance for clinical diagnosis and treatment. Methods Clinical data of children with KD who were admitted to the department of pediatric cardiology of a tertiary general hospital from January 2018 to March 2021 were analyzed retrospectively, patients were divided into KD complicated with MP infection group(KD-MP group)and KD without MP infection group (KD group), differences in platelet parameters, coagulation-related indexes, myocardial enzyme spectrum and incidence of adverse outcomes between two groups of children were compared. Results A total of 270 children with KD were included in analysis, including 70 cases in KD-MP group and 200 cases in KD group. The median level of mean platelet volume (MPV) in KD-MP group was higher than that in KD group (10.00 [9.08, 11.00] fL vs 9.60 [8.83, 10.68] fL, P < 0.05). The proportions of coronary artery lesion, mild coronary artery dilatation and pericardial effusion in KD-MP group were 55.71%, 47.14% and 15.71% respectively, which were higher than 38.50%, 30.50% and 5.50% in KD group (all P < 0.05). Conclusion KD patients complicated with MP infection are more likely to suffer from coronary artery lesion and pericardial effusion, and face a greater risk of cardiovascular lesion, clinicians should take anti-infective treatment in time.

Abstract:Objective To explore the application effect of precise prevention and control measures on reducing central venous catheter-related bloodstream infection (CRBSI). Methods Patients with central venous catheterization ≥48 hours in a tertiary first-class hospital from January 2019 to December 2020 were selected. January to December 2019 was pre-intervention period, the whole hospital began to implement precise prevention and control measures at the end of December 2019, and January to December 2020 was post-intervention period. Implementation rate of CRBSI prevention and control measures of health care workers and incidence of CRBSI among patients before and after intervention was compared. Results The implementation rate of CRBSI prevention and control measures in 2020 was 99.06%(191 504/193 324), which was higher than 87.90%(382 550/435 194)in 2019, difference was significant (χ²=21 046.64, P < 0.001). There were 54 and 11 cases of CRBSI in 2019 and 2020 respectively, there were no significant differences in gender, age, leukocyte count, procalcitonin and C-reactive protein between two groups of patients (all P>0.05). The total catheterization days in 2019 was 350 473 days, incidence of CRBSI was 0.15‰; the total catheterization days in 2020 was 186 856 days, incidence of CRBSI was 0.06‰, difference in incidence of CRBSI between two groups of patients was significant(χ²=5.912, P=0.015). Conclusion Implementation of precise prevention and control measures can reduce the incidence of central venous CRBSI in patients undergoing central venous catheterization.

Abstract:Objective To analyze the molecular biological characteristics and antimicrobial resistance of Staphylococcus aureus (SA) isolated from hands of medical staff in Shanghai City. Methods From 2018 to 2020, medical staff of 16 different levels of hospitals in Shanghai were selected as the research objects, hands of medical staff in key departments of medical institutions were sampled, SA was isolated, identified and performed antimicrobial susceptibility testing, pulsed-field gel electrophoresis (PFGE) and whole genome sequencing, the whole genome data were assembled by BioNumerics software, the assembled genomes were conducted multilocus sequence typing (MLST), core genome multilocus sequence typing (cgMLST), virulence genes, drug resistance genes and disinfec-tant resistance genes analysis. Results The isolation rate of SA from hands of medical staff in Shanghai from 2018 to 2020 was 2.9%. Methicillin-resistant SA (MRSA) accounted for 13.6% (3/22), methicillin-susceptible SA (MSSA) accounted for 86.4% (19/22). Three MRSA strains were from doctors, nurses and carers respectively, and 1 MRSA strain from doctors carried qacB gene. MSSA has different resistance to erythromycin, ciprofloxacin, tetracycline and levofloxacin; PFGE and cgMLST showed the genetic diversity of SA, PFGE bands of 2 strains of ST72 SA from the same source were highly similar, and there were only 10 differential genes, suggesting that they were clonal strains. Conclusion Hands of medical staff in medical institutions can be used as a carrier for the transmission of SA, there is transmission of SA through hands as a carrier in medical institutions.

Abstract:Objective To explore the clinical characteristics and prognostic risk factors for elderly patients with sepsis. Methods The elderly patients with sepsis treated in a tertiary first-class hospital from July 2020 to September 2021 were selected, clinical and laboratory data of patients were recorded, patients were divided into survival group and death group according to 28-day prognosis, differences in clinical indicators between two groups were compared, independent risk factors for prognosis of elderly patients with sepsis were analyzed by binary logistic regression analysis, receiver operating characteristic curve(ROC) was drawn to evaluate the effect of different indicators on predicting the prognosis of patients. Results A total of 121 patients were included in analysis, including 74 cases of sepsis and 47 cases of septic shock. 92 patients were in survival group and 29 in death group. Compared with the survival group, the proportion of septic shock and the number of complications ≥2 in death group was higher (P < 0.05); the scores of sequential organ failure assessment(SOFA)and acute physiology and chronic health evaluation (APACHE Ⅱ) were higher, the expression levels of interleukin 6(IL-6), cystatin C (Cys-C), procalcitonin (PCT), prothrombin time (PT), and D-dimer (D -D) all enhanced (all P < 0.05), while expression level of absolute lymphocyte count (ALC) and expression of albumin (ALB) dropped (both P < 0.01). Binary logistic regression analysis showed that septic shock, SOFA score, D -D and expression of Cys-C were independent risk factors affecting the 28-day prognosis of elderly patients with sepsis. ROC curve analysis showed that SOFA score (AUC=0.758), D -D (AUC=0.774) and Cys-C (AUC=0.650) had a certain value for the prediction of prognosis of patients (all P < 0.01), compared with a single indicator, the combined detection of three indicators showed a higher predictive value (AUC=0.882). Conclusion Occurrence of septic shock, increase of SOFA score as well as enhanced expression of D -D and Cys-C are independent risk factors leading to the increase of mortality in elderly patients with sepsis. The combined detection of SOFA score, D -D and Cys-C can further improve the predictive value of prognosis in patients with sepsis, and provide reference basis for clinical treatment and prognosis evaluation.

Abstract:Objective To evaluate the risk factors for catheter-related bloodstream infection (CRBSI) in very low birth weight infants (VLBWIs) receiving peripherally inserted central venous catheter (PICC). Methods VLBWIs who received PICC in neonatal intensive care unit (NICU) in the Third Affiliated Hospital of Zhengzhou University from January 2019 to November 2021 were selected. Clinical data of VLBWIs were analyzed retrospectively, case-control study was adopted, neonates with CRBSI were as case group and those without CRBSI were as control group, risk factors for CRBSI were analyzed by univariate and logistic regression. Results A total of 61 VLBWIs receiving PICC developed CRBSI, the total catheterization time was 26 521 days, incidence of CRBSI was 2.3 ‰. The main pathogens of CRBSI in VLBWIs were Staphylococcus epidermidis (23.0%), Klebsiella pneumoniae (19.7%) and Serratia marcescens (14.8%). Logistic regression analysis showed that birth weight < 1 000 g (OR=2.254), mechanical ventilation (OR=2.168), catheterization time ≤7 days (OR=2.534), PICC indwelling time≥21 days (OR=2.200) were independent risk factors for CRBSI in VLBWIs, and one-time puncture success (OR=0.378) was protective factor. Conclusion For VLBWIs, especially those with extremely low birth weight < 1 000 g, early postnatal catheterization and repeated puncture during catheterization should be avoided as much as possible, the indwelling time of PICC and mechanical ventilation time should be shortened as much as possible, which is of great significance for the prevention of CRBSI.

Abstract:Objective To explore the value of intelligent endoscope storage cabinet and standard endoscope storage cabinet in drying digestive endoscope lumen. Methods 240 endoscopes were divided into 30 seconds (30 s), 40 s, and 50 s inflation groups according to the time required to inflate the biopsy lumen with pressure air gun, with 80 pieces in each group. After the completion of inflation, 13, 30, 41 pieces of dried endoscopes were excluded from the 30 s, 40 s, and 50 s inflation groups, drying unqualified endoscopes in each group were divided into trial group and control group by random number method, endoscopes in trial group and control group were placed in intelligent and standard endoscope storage cabinet respectively. When endoscopes were placed for 1, 2, 3, 6, and 24 hours, the moisture test was performed to detect whether the lumen contained residual droplets. Results The qualified rates of endoscopic lumen drying in 30 s, 40 s and 50 s inflation groups were 16.25%, 37.50% and 51.25% respectively, difference among three groups was significant (P < 0.05). After endoscopes in inflation groups were placed in the storage cabinet for 1, 2, 3 and 6 hours, there was significant difference in the qualified rate of endoscopic lumen drying between intelligent cabinet and standard cabinet (both P < 0.05). Lumen of all reprocessed endoscopes could achieve complete drying when endoscopes were placed in intelligent cabinet for 1 hour. When endoscopes in 30 s and 40 s inflation groups were placed for 24 hours, qualified rate of lumen drying between intelligent cabinet and standard cabinet was still significantly different (both P < 0.05), when endoscopes in 50 s inflation group were placed for 24 hours, qualified rate of lumen drying between intelligent cabinet and standard cabinet was no significantly different (both P>0.05). Conclusion Intelligent cabinet is beneficial to the rapid drying of endoscope lumen and reduces the risk of microbial growth, which is worthy of popularization and application.

Abstract:Infection is one of the common complications in patients with nephrotic syndrome, and it is also an important cause of death. Early and accurate diagnosis of infectious pathogens is helpful for targeted treatment and improving the prognosis of patients. Nowadays, the main method of pathogen detection is culture method, the positive rate of pathogen detection is low because of immunosuppression of patients and the influence of different sampling and detection methods. High-throughput sequencing technique effectively complements the shortcomings of traditional culture methods with its advantages of rapidness, sensitivity and wide coverage. This paper reports one case of nephrotic syndrome complicated with cryptococcal infection and one case complicated with Stenotrophomonas maltophilia meningitis confirmed by high-throughput sequencing, suggesting that high-throughput sequencing technique has significant advantages and great application value in the diagnosis of nephrotic syndrome complicated with infection which is negative through traditional pathogen culture.

Abstract:Tuberculosis has brought serious disease burden to the world, prevention and control of tuberculosis is of great significance. Molecular epidemiology of tuberculosis integrates the technique of Mycobacterium tuberculosis typing and epidemiological data, and plays an extremely important role in the study of the spread and epidemic characteristics of tuberculosis. Whole genome sequencing (WGS) can construct complete DNA sequences of the genome of an organism, which has the advantages of high resolution, high throughput and accurate results, it is very attractive and has great development potential in the study of molecular epidemiology of tuberculosis. This paper compares WGS technique with the traditional Mycobacterium tuberculosis typing technique, points advantages of WGS, introduces technical route and progress of WGS, reviews its application achievements in epidemic tracing, drug resistance research and mixed infection diagnosis, so as to provide reference and support for prevention, control and research of tuberculosis.

Abstract:Left ventricular assist is now the main surgical treatment strategy for patients with end-stage heart fai-lure, while it improves survival in heart failure patients, it often leads to a number of serious complications. Ventri-cular assist device-specific infection, particularly driveline infection, is a common post-operative complication in ventricular assist patients. Biofilm formation and migration promote the infection spread to deeper tissues such as the pump cavity and blood stream, making subsequent treatment more difficult and even endangering the patient's life. This article reviews the current status of left ventricular assist device driveline infection in terms of epidemiological characteristics, pathogenic mechanisms, diagnosis, as well as prevention and treatment.