Distribution Of Pathogenic Bacteria Research Articles

Evaluation and comparison of tympanoplasty efficacy with tympanic membrane perforation after chronic suppurative otitis media in dry ear with different microorganisms

ObjectiveTo investigate the distribution of pathogenic bacteria in patients with tympanic membrane perforation after chronic suppurative otitis media (CSOM) in dry ear and its influence on the success rate of tympanoplasty and postoperative infection. Methods740 patients with tympanic membrane perforation after CSOM underwent endoscopic tympanoplasty were selected. The mucosal surface secretion of middle-ear was collected for bacterial culture and drug sensitivity test. The patients were followed up several times from 1 week to 3 months after the surgery. Results740 cases of ear secretions samples, raise the pathogens of 208 cases (28.1%), the success rate of surgery with microorganism grown and with no grown was 93.8% and 91.5%. fungus (14.6%) was the most species among the patients with the positive result, followed by methicillin-sensitive Staphylococcus aureus (4.1%), Pseudomonas (2.0%), Staphylococcus epidermidis (1.9%), methicillin-resistant Staphylococcus aureus (1.6%) and so on. There was no statistical difference in the proportion of perforation and infection in each group. There were no statistically significant differences in gender, age and duration of disease among the groups. ConclusionThere were still microbial colonization in patients with tympanic membrane perforation after CSOM in dry ear, include fungus, Staphylococcus aureus and Pseudomonas aeruginosa. Different microbial colonization had no influence on the success rate of tympanoplasty and postoperative infection.

Pathogens' distribution and changes of antimicrobial resistance in the bile of acute biliary tract infection patients

Objective: To investigate the pathogens' distribution and antimicrobial resistance in the bile of acute biliary tract infection patients. Methods: The data of bile bacterial culture and drug sensitivity test of 223 acute biliary tract infection patients who underwent gallbladder puncture or endoscopic retrograde cholangiopancreatography drainage from July 2009 to July 2019 were analyzed retrospectively at Department of General Surgery,Xinhua Hospital,Affiliated to Shanghai Jiao Tong University School of Medicine.There were 141 males and 82 females with age of 67.3 years(range:28 to 93 years).Three to five milliliter of bile was extracted from each patient and sent to the laboratory for bacterial culture,identification and drug sensitivity test.The patients were divided into two groups according to the visiting time: the former group (n=124) was admitted from July 2009 to July 2014,and the latter group(n=99) was admitted from August 2014 to July 2019.The distribution of pathogenic bacteria and the changing trend of drug resistance rate of common bacteria in the two groups were compared.The results of drug sensitivity test were analyzed by WHONET software provided by WHO bacterial surveillance network.The drug resistance rates in different time periods were compared by χ2 test. Results: In this study,there were 147 cases of acute cholangitis and 76 cases of acute cholecystitis.A total of 376 strains of pathogenic bacteria were cultured.Among them,98 strains(26.1%) were gram-positive bacteria,269 strains(71.5%) were gram-negative bacteria and 9 strains(2.4%) were fungi.The top three gram-positive bacteria were Enterococcus faecium (49.0%,48/98),Enterococcus faecalis(20.4%,20/98),and Enterococcus luteus(7.1%,7/98).The top 5 gram-negative bacteria were Escherichia coli(33.5%,90/269),Klebsiella pneumoniae(13.8%,37/269),Pseudomonas aeruginosa(13.0%,35/269),Acinetobacter baumannii (12.6%,34/269),and Enterobacter cloacae(4.8%,13/269).From 2009 to 2019,there was no significant change in the proportion of gram-positive bacteria (former group vs. latter group: 25.3% vs. 28.2%) and gram-negative bacteria(former group vs.latter group: 74.7% vs. 71.8%) in the bile of patients with acute biliary tract infection.Gram-positive bacteria were mainly Enterococci(85.7%,84/98) and gram-negative bacteria were Escherichia coli(33.5%,90/269).Acinetobacter baumannii accounted for 7.8%(11/142) of gram-negative bacteria in the former group and 18.1%(23/127) in the latter group,an increase of 10.3% over previous five years.Pseudomonas aeruginosa had a downward trend,16.9% in the former group(24/142) and 8.7% in the latter group (11/127),the proportion decreased by 8.2%,and the other changes were not significant.The drug resistance rates of common gram-positive bacteria were relatively stable,and the drug resistance rates of Enterococcus faecium to many antibiotics were higher than those of Enterococcus faecalis.The resistance rates of gram-negative bacteria to most antibiotics showed an upward trend,among which Klebsiella pneumoniae showed an upward trend to most of antibiotics(former group: 0/15－4/13, latter group: 55.0%－70.0%; χ2=3.996－16.942, P=0.000－0.046).The drug resistance rates of Acinetobacter baumannii was generally higher,but there were no significant changes in the drug resistance rates of Acinetobacter baumannii between the two groups.The drug resistance rates of Pseudomonas aeruginosa to most antibiotics increased,and the overall drug resistance rates of Escherichia coli were stable and showed a slight upward trend. Conclusions: The main pathogens in bile of patients with acute biliary tract infection are gram-negative bacteria.The constituent ratio of various gram-negative bacteria had no significant change from 2009 to 2019,but the drug resistance rates shows an upward trend.Among the gram-negative bacteria, Escherichia coli is the most important pathogen,and the proportion has no significant change.The proportion of Acinetobacter baumannii in the former group was significantly higher than that in the former group.And the proportion of Pseudomonas aeruginosa has a decreased trend.

Clinical Analysis of Bloodstream Infections During Agranulocytosis After Allogeneic Hematopoietic Stem Cell Transplantation.

PurposeTo explore the epidemiological characteristics and risk factors of bloodstream infections (BSI) in patients who develop agranulocytosis fever after allogeneic hematopoietic stem cell transplantation (allo-HSCT). This study also provides a basis for the clinical treatment of BSI.MethodsA retrospective analysis of 397 allo-HSCT patients in the Department of Hematology of our hospital was conducted from January 2013 to December 2017 to analyze the incidence of BSI, the distribution and types of pathogenic bacteria, and drug resistance rates. We also determined whether various parameters are risk factors to BSI, including the patient age, gender, disease type, transplantation method, stem cell source, pre-treatment with anti-thymocyte globulin (ATG), and agranulocytosis time.ResultsAmong the 397 allo-HSCT patients, 294 had a fever during the period of agranulocytosis, and 52 cases were found to have BSI. The incidence of BSI in patients with agranulocytosis fever was 17.7% (52/294). Among the 60 pathogens detected, 43 (71.67%), 10 (16.67%), and 7 (11.67%) were Gram negative strains, Gram positive strains, and fungi, respectively. The most common bacteria were Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa. The detection rate of extended-spectrum β-lactamase (ESBL) was 40.0%, and carbapenem-resistant Enterobacteriaceae (CRE) accounted for 17.9%. Single-factor and multi-factor analyses showed that pre-treatment with ATG, agranulocytosis time (≥21 days), and stem cell source were risk factors for BSI.ConclusionWe found that in our hospital, BSIs in allo-HSCT patients are mainly caused by Gram-negative bacteria, and the resistance rate to carbapenem drugs is high. Pre-treatment with ATG, agranulocytosis time (≥21 days), and stem cell source are risk factors for BSI.

Distribution and drug resistance of pathogens causing periprosthetic infections after hip and knee arthroplasty

To study the distribution and drug resistance of pathogens causing periprosthetic infections after hip and knee arthroplasty, and to formulate prevention and treatment strategies for drug-resistant bacteria. The data of 146 cases of periprosthetic infection after primary hip and knee arthroplasty from 2010 to 2015 were collected, including 111 cases of periprosthetic infection after hip arthroplasty and 35 cases of periprosthetic infection after knee arthroplasty. The culture positive rate, pathogenic bacteria composition and drug resistance rate were counted over the years, and the change trend of pathogen distribution and drug resistance was analyzed. One hundredand eight strains of pathogenic bacteria were detected in 146 cases, and the positive rate of culture was 73.97%. Gram positive bacteria accounted for 55.48%, Staphylococcus epidermidis and Staphylococcus aureus accounted for 25.34% and 15.07% respectively. Gram negative bacteria accounted for 13.01%, including Enterobacter cloacae, Pseudomonas aeruginosa and Escherichia coli. There were 4 cases of Mycobacterium tuberculosis infection and mixed infection. The results of culture over the years showed that the constituent ratio of Gram positive bacteria had an increasing trend, fluctuating from 39.13% to 76.47%. The results of drug sensitivity showed that the pathogens were highly resistant to β-lactams, quinolones, clindamycin and gentamicin, and the drug resistance rate was increasing, but it was still sensitive to rifampicin, nitrofurantoin, tigecycline, linezolid and vancomycin. Gram positive bacteria are the main pathogens of periprosthetic infection, and the proportion is increasing gradually.The pathogens have high resistance to many kinds of antibiotics, and the resistance rate is still increasing. To strengthen the monitoring of the distribution and drug resistance of pathogenic bacteria is helpful to grasp its change trend and formulate targeted prevention and control strategies.

Influence of anthropogenic activities on the spatial distribution of heterotrophic, indicator and pathogenic bacteria around Andaman and Nicobar Islands

To examine the influence of anthropogenic activities on the marine ecosystem around the Andaman and Nicobar Islands, a study was conducted to investigate the abundance of heterotrophic, indicator and pathogenic bacteria during the monsoon season. We noticed the higher abundance of heterotrophic, indicator (Escherichia coli and Enterococcus faecalis) and pathogenic bacterial counts (Aeromonas hydrophila, Enterobacter aerogens, Escherichia coli strain O157:H7, Shigella dysenteriae and Vibrio parahaemolyticus) near the 10o channel, which is the principal route to reach Andaman mainland. Most of the stations are offshore (chosen to cover shipping tracks) at a distance ranging from 41 to 266 km from the coast. The nearest station to the coast was at 21 km away. Apart from those mentioned above, several other pathogenic bacteria were also detected such as Klebsiella pneumoniae, Salmonella paratyphi, Vibrio cholera and Vibrio vulnificus but they are sparsely detected at few stations only.

The size distribution of airborne bacteria and human pathogenic bacteria in a commercial composting plant

Composting plants are regarded as one of the important sources of environmental bioaerosols. However, limitations in the size distribution of airborne bacteria have prevented our comprehensive understanding of their risk to human health and their dispersal behavior. In this study, different sizes of airborne bacteria were collected using an eight-stage impactor from a full-scale composting facility. Size-related abundance and communities of airborne bacteria as well as human pathogenic bacteria (HPB) were investigated using 16S rRNA gene sequencing coupled with droplet digital PCR. Our results indicate that the bacterial concentrations from the eight stages were approximately 104–105copies/m3. Although no statistical correlation was detected between the particle size and the Shannon index, the influence of size on bacterial lineages was observed in both composting and packaging areas. For airborne bacteria from different stages, the dominant phyla were Firmicutes, Proteobacteria, and Actinobacteria, and the dominant genera was Bacillus. Seven out of eight HPB with a small geometric mean aerodynamic diameter had a high concentration in composting areas. Based on diameters of 2.42 to 5.09 µm, most HPB in the composting areas were expected to be deposited on the bronchus and secondary bronchus. However, in the packaging areas, the deposition of HPB (diameters 3.70 to 8.96 µm) occurred in the upper part of the respiratory tract. Our results on the size distribution, abundance, and diversity of these bacteria offer important information for the systematic evaluation of bacterial pathogenicity and the potential health impacts on workers in composting plants and the surrounding residents.

Determining the prevalence, identity and possible origin of bacterial pathogens in soil.

Soil biomes are vast, exceptionally diverse and crucial to the health of ecosystems and societies. Soils also contain an appreciable, but understudied, diversity of opportunistic human pathogens. With climate change and other forms of environmental degradation potentially increasing exposure risks to soilborne pathogens, it is necessary to gain a better understanding of their ecological drivers. Here we use the Galleria mellonella insect virulence model to selectively isolate pathogenic bacteria from soils in Cornwall (UK). We find a high prevalence of pathogenic soil bacteria with two genera, Providencia and Serratia, being especially common. Providencia alcalifaciens, P. rustigianii, Serratia liquefaciens and S. plymuthica strains were studied in more detail using phenotypic virulence and antibiotic resistance assays and whole-genome sequencing. Both genera displayed low levels of antibiotic resistance and antibiotic resistance gene carriage. However, Serratia isolates were found to carry the recently characterized metallo-β-lactamase blaSPR-1 that, although not conferring high levels of resistance in these strains, poses a potential risk of horizontal transfer to other pathogens where it could be fully functional. The Galleria assay can be a useful approach to uncover the distribution and identity of pathogenic bacteria in the environment, as well as uncover resistance genes with an environmental origin.

Retrospective Study of the Etiology and Risk Factors of Systemic Inflammatory Response Syndrome After Systematic Transrectal Ultrasound-Guided Prostate Biopsy.

ObjectiveTo explore the risk factors, pathogenic bacteria distribution and drug resistance of systematic transrectal ultrasound-guided prostate biopsy (TRUS-Bx), 329 cases of TRUS-Bx were collected, retrospectively, in the Second Affiliated Hospital, Army Military Medical University, from April 2017 to October 2019.MethodsA total of 329 cases were all qualified and grouped into the SIRS group (25 cases) and the non-SIRS group (304 cases). Of all the cases, incidence and risk factors of systemic inflammatory response syndrome (SIRS) were analyzed. Urine and blood samples of patients with SIRS after TRUS-Bx were also collected for bacterial culture and drug sensitivity test.ResultsMultivariate logistic regression analysis showed that BMI ≥ 25 kg/m2 (OR = 1.66, 95% CI = 1.34–2.12, P <0.001), history of diabetes (OR = 5.48, 95% CI = 1.53–19.68, P = 0.008), urinary infection before operation (OR = 9.19, 95% CI = 2.92–20.93, P < 0.001) and erythrocyte sedimentation (ESR) ≥ 20 mm/h (OR = 1.04, 95% CI = 1.01–1.08, P = 0.039) were independent risk factors of SIRS after TURS-PB.ConclusionThe incidence of SIRS and urinary sepsis was 7.59% and 2.13%, respectively, and major pathogens of SIRS after TRUS-Bx were Escherichia coli (58.33%), Klebsiella pneumoniae (12.5%) and Pseudomonas aeruginosa (12.5%). Imipenem, meropenem, tigecycline, piperacillin/tazobactam, teicoplanin, vancomycin, amikacin and cefoperazone/sulbactam had a very strong inhibitory effect to those pathogenic bacteria (sensitivity 85.72%~100%). Levofloxacin, ciprofloxacin, gentamicin, penicillin G, compound neonomine and second-generation cephalosporins showed less but also worked as a good inhibitor to pathogenic bacteria (42.86%~80.95%).

Biovolume and spatial distribution of foodborne Gram-negative and Gram-positive pathogenic bacteria in mono- and dual-species biofilms

The objective of this study was to characterize the biofilms formed by Salmonella enterica serotype Agona, Listeria monocytogenes, methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus faecium (VRE) after 12, 48, 72, 120 and 240 h of incubation at 10 °C. Biofilms containing a single species, together with dual-species biofilms in which S. enterica and a Gram-positive bacterium existed in combination, were formed on polystyrene and evaluated by using confocal laser scanning microscopy (CLSM). All strains were able to form biofilm. The greatest biovolume in the observation field of 14,161 μm2 was observed for mono-species biofilms after 72 h, where biovolumes of 94,409.0 μm3 ± 2131.0 μm3 (S. enterica), 58,418.3 μm3 ± 5944.9 μm3 (L. monocytogenes), 68,020.8 μm3 ± 5812.3 μm3 (MRSA) and 59,280.0 μm3 ± 4032.9 μm3 (VRE) were obtained. In comparison with single-species biofilms, the biovolume of S. enterica was higher in the presence of MRSA or VRE after 48, 72 and 120 h. In dual-species biofilms, the bacteria showed a double-layer distribution pattern, with S. enterica in the top layer and Gram-positive bacteria in the bottom layer. This spatial disposition should be taken into account when effective strategies to eliminate biofilms are being developed.

Distribution of pathogenic bacteria in lower respiratory tract infection in lung cancer patients after chemotherapy and analysis of integron resistance genes in respiratory tract isolates of uninfected patients.

BackgroundWe studied the distribution of pathogenic bacteria in lower respiratory tract infection in lung cancer patients after chemotherapy and analyzed the integron resistance genes in respiratory tract isolates of uninfected patients.MethodsRetrospective analysis was used to select sputum samples from 400 lung cancer patients after chemotherapy admitted in Fuyang People’s Hospital from July 2017 to July 2019. Culture, isolation and identification of strains were conducted in accordance with the national clinical examination operating procedures.ResultsA total of 134 strains were identified. In 120 patients with pulmonary infection, 114 strains were cultured. Twenty strains of klebsiella pneumoniae were cultured in 280 patients without pulmonary infection. Among the 134 strains, the detection rate of gram-negative bacteria was 79.10%. The first four strains were Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosa, and Haemophilus influenzae. The gram-positive bacteria detection rate was 4.47%, mainly Staphylococcus aureus and Streptococcus. The fungus detection rate was 16.42%. The drug sensitivity results showed that the resistance rate of gram-negative bacillus to penicillin and cephalosporin was higher, and were more sensitive to carbapenem, piperacillin tazobactam and cefoperazone sulbactam. Gram-positive cocci were resistant to penicillin, macrolide and clindamycin, and sensitive to linezolid, vancomycin and rifampicin. All strains of fungal culture were candida albicans, which were sensitive to common antifungal drugs. Among the 20 strains of klebsiella pneumoniae cultured in sputum specimens of non-infected patients with lung cancer undergoing chemotherapy, 2 strains were integron-positive strains, and all of them were class I integrons.ConclusionsLung cancer patients after chemotherapy have a high resistance to commonly used antimicrobial drugs, so it is necessary to detect the resistance of pathogenic microorganisms in clinical practice. The strains carried by patients with lung cancer without pulmonary infection during chemotherapy can isolate type I integrons, suggesting that the spread of drug resistance at gene level should be closely detected.

Responses of bacterial communities and resistance genes on microplastics to antibiotics and heavy metals in sewage environment

In present study, copper (Cu), zinc (Zn), tetracycline (TC) and ampicillin (AMP) were selected to study the individual and synergistic effects of antibiotics and heavy metals on the microbial communities and resistance genes on polyvinyl chloride microplastics (PVC MPs) and surrounding sewage after 28 and 84 days. The results indicated that PVC MPs enriched many microorganisms from surrounding sewage, especially pathogenic bacteria such as Mycobacterium and Aquabacterium. The resistance gene with the highest abundance enriched on PVC MPs was tnpA (average abundance of 1.0 × 107 copies/mL sewage). The single presence of Zn, TC and AMP inhibited these enrichments for a short period of time (28 days). But the single presence of Cu and the co-existence of antibiotics and heavy metals inhibited these enrichments for a long period of time (84 days), resulting in relatively low microbial diversities and resistance genes abundances. Transpose tnpA had significantly positive correlations (p < 0.05) with all other genes. Pathogenic bacteria Mycobacterium and Legionella were potential hosts harboring 5 and 1 resistance genes, respectively. Overall, PVC MPs played important roles in the distribution and transfer of pathogenic bacteria and resistance genes in sewage with the presence of antibiotics or (and) heavy metals.

Current Status and Prospects of Spontaneous Peritonitis in Patients with Cirrhosis.

Spontaneous bacterial peritonitis (SBP) is a common cirrhotic ascites complication which exacerbates the patient's condition. SBP is caused by gram-negative bacilli and, to a lesser extent, gram-positive cocci. Hospital-acquired infections show higher levels of drug-resistant bacteria. Geographical location influences pathogenic bacteria distribution; therefore, different hospitals in the same country record different bacteria strains. Intestinal changes and a weak immune system in patients with liver cirrhosis lead to bacterial translocation thus causing SBP. Early diagnosis and timely treatment are important in SBP management. When the treatment effect is not effective, other rare pathogens should be explored.

Distribution and Drug Sensitivity of Pathogens Causing Nosocomial Infection in Patients with Hematological Granulocytosis

To investigate the distribution and drug resistance of nosocomial infection pathogens in AL patients with hematological agranulocytosis, so as to provide evidence for the clinical rational use of antibiotics. Pathogenic data of 504 hospitalized patients with agranulocytosis caused by nosocomial infection in the Department of Hematology, the First Hospital of Lanzhou University from May 2015 to May 2018 were collected and retrospectively analyzed for the distribution of pathogenic bacteria and the results of drug susceptibility. The isolated pathogenic bacteria strains amounted to 184, out of which, 168 strains (91.3%) orginated from the patients with acute leukemia, while 16 strains (8.7%) originated from the patients with non-acute leukemia. The positive samples mainly originated from blood stream, the isolated bacteria from which were 81 straims (44%); then originated from sputam and pharynx swabs, from which isolated bacteria amounted to 54 strains (29.3%) and 35 strains (19%) respectively. In the pathogenic bacteria, the Gram-negative bacteria amounted to 126 strains accounting for 68.46%, out of which the most commond bacteria strains were Klebseilla pneumoniae, cscherichia coli and Pseudomonas aeruginosa; the Gram positive bocteria amounted to 23 strains accounting for 12.5%, mainly staphy lococeus anreus, and Staphylococcus epitermidis; the fungi amounted to 35 strains accounting for 19.02%, mainly Candida albicans. The detection rates of Escherichia coli and Klebsiella pneumoniae producing extended-spectrum β-lactamases (ESBLs) were 40.0% and 22.2%, respectively. They were 100% sensitive to amikacin and 27.8% resistant to carbapenems. Klebsiella pneumoniae had the highest sensitivity to amikacin, 94.44% to ampicillin, 97.22% to carbapenems and 100% sensitive to ammonia. Their penicillin-resistance rate was the highest, up to 80%; Pseudomonas aeruginosa was sensitive to the antibiotics (＞80%）. Methicillin-resistant Staphylococcus aureus and methicillin-resistant coagulase-negative Staphylococcus were detected in Gram-positive bacteria. The susceptibility rate of main Gram-positive bacteria to vancomycin and linezolid was 100%, and they were 100% resistant to penicillin. Gram-negative bacteria are the main pathogens of nosocomial infection in patients with hematological agranulocytosis. Pathogens have different resistance to antimicrobial agents. It is important to know the distribution and susceptibility of common pathogens for rational selection of antimicrobial agents and control of nosocomial infection.

The prevalence and antimicrobial resistance phenotypes of Salmonella, Escherichia coli and Enterococcus sp. in surface water.

Surface water is prone to bacterial contamination as it receives wastes and pollutants from human and animal sources, and contaminated water may expose local populations to health risks. This review provides a brief overview on the prevalence and antimicrobial resistance (AR) phenotypes of Salmonella, Escherichia coli and Enterococcus, found in natural freshwaters. These bacteria are frequently detected in surface waters, sometimes as etiological agents of waterborne infections, and AR strains are not uncommonly identified in both developed and developing countries. Data relating to Salmonella, E. coli and Enterococcus present in environmental water are lacking, and in order to understand their development and dissemination using the One Health approach, understanding the prevalence, distribution and characteristics of the bacteria present in surface water as well as their potential sources is important. Furthermore, AR bacteria in natural watersheds are not well investigated and their impacts on human health and food safety are not well understood. As surface water is a receptacle for AR bacteria from human and animal sources and a vehicle for their dissemination, this is a crucial data gap in understanding AR and minimizing its spread. For this review, Salmonella, E. coli and Enterococcus were chosen to evaluate the presence of primary pathogens and opportunistic pathogens as well as to monitor AR trends in the environmental water. Studies around the world have demonstrated the widespread distribution of pathogenic and AR bacteria in surface waters of both developing and developed countries, confirming the importance of environmental waters as a reservoir for these bacteria and the need for more attention on the environmental bacteria for emerging AR.

Molecular Identification of Pathogenic Leptospirosis with Zoonotic Potential in Urban Rats (Rattus Rattus) in Banyuwangi District

Leptospirosis is a zoonotic disease that occurs globally. Leptospires are transmitted through the urine of infected mice, through injured skin or mucosal invasion. Infection can occur through direct contact or through contact with contaminated water or soil. This qualitative research uses a combination of epidemiological studies with a case study approach. Rat urine metabolism samples will be tested by testing the base pair chain through the Polymerase Chain Reaction method for leptospirosis. Electrophoresis results showed 5% percent of positive samples with 330 bp. The conclusion of this study, the molecular identification of leptospirosis from rat urine using the Polymerase Chain Reaction technique are found positive results so prevention is needed to control the distribution of pathogenic leptospirosis bacteria. Urban rats (Rattus rattus) in leptospirosis transmission are considered as the most important leptospira reservoir, because high population densities of this species can cause an increase in the spread of leptospirosis. Keywords: Banyuwangi, Leptospirosis, Urban rats, Zoonosis

Changes in immune indicators and bacteriologic profile were associated with patients with ventilator-associated pneumonia.

The aim of this study is to explore and identify ventilator-associated pneumonia (VAP)-related prognostic immune factors and further detect the drug-resistant pathogens to establish the theoretical guidance for clinical prevention and treatment strategies of VAP. A total of 478 patients using ventilator who were hospitalized in July 2014 to November 2016 in our hospital were enrolled in this study. About 103 patients with VAP (21.5%, 103/478) among 478 cases of patients using ventilator. Among the 103 patients with VAP, the distribution of pathogenic bacteria and drug resistance in patients with VAP were detected and analyzed. In the VAP group, 35 patients died and 43 patients had simultaneous sepsis. Compared with those of non-VAP group, the proportion of CD3+ (P = .012), CD3+CD4+ (P = .024) and CD8+CD28+ ( P = .017) T cells in VAP group increased significantly, which indicated more severe immune response. Multivariate regression model analysis revealed that tracheotomy of mechanical ventilation (P = .013), mechanical ventilation time ≥7 days (P = .02) and aspiration and reflux (P = .011) were independent risk factors associated with VAP. According to the results of bacterial culture and drug sensitivity test, rational selection of antibiotics and monitoring of patients within intensive care unit can effectively control the incidence of VAP and improve the prognosis of patients.

Clinical Features of Infection within 100 days after Hematopoietic Stem Cell Transplantation in 313 patients with Hematologic Diseases

To analyze the clinical characteristics of infection within 100 days after hematopoietic stem cell transplantation (HSCT) in patients with hematologic disease. The culture results of 313 HSCT patients infected in the hematology department of our hospital from January 2013 to January 2019 were collected, and the infection incidence, pathogen distribution, drug susceptibility test results and infection risk factors out of them all were analyzed. Among 313 HSCT patients, infection occurred within 100 days in 262(83.7%) patients, 234 (89.3%) cases were in neutropenic period at infection onset. 156 pathogen distributions showed that the bloodstream infection (64.1%) ranked first. Among isolates, Gram-negative bacteria was 86 (55.1%), which were higher than Gram-positive bacteria (49, 31.4%), and fungi was 21(13.5%). The prevalence of ESBLs in E.coli and Klebsiella pneumoniae were 36.4% and 31.6%, respectively. The drug resistance rates of E.coli and Klebsiella pneumoniae to carbapenems were 18.20% and 5.3%, respectively, and to amikacin were 29.5% and 10.5%, respectively. The antimicrobial resistance of fermentation bacteria was significantly different. The drug resistence rates of Pseudomonas aeruginosa and Acinetobacter baumannii to carbapenems were high. Only one strain of methicillin-resistant staphylococcus aureus (MRSA) was found. The drug resistence rates of enterococcus faecalis to linezolid was 14.30%. The sensitivity of other Gram-positive bacteria to vancomycin, teicolanin and linezolid was 100%. The HSCT in our hospital was mainly allogeneic, and univariate analysis showed that the risk factors for infection were status before trasplantion, HLA matching type,length of stay for the first transplant, and length of neutropenia, while Mulvariate analysis showed that only HLA matching type showed statistical significance. The infection of patients after HSCT occurrs in period of neutropenia, Most of pathogens are G- bacteria, and the resistance to antibiotics is quite common, HLA mismatch is allo-HSCT independent risk factors for infection. It is very imprtant to monitor actively the distribution of pathogenic bacteria, drug-resistance and risk factors of infection for guiding more reasonable and standardized clinical treatment.

Serum D-dimer as a diagnostic index of PJI and retrospective analysis of etiology in patients with PJI

ObjectivesTo investigate the diagnostic value of serum D-dimer in patients with periprosthetic joint infection (PJI). Moreover, to provide evidence for the treatment of PJI by investigating distribution of pathogenic bacteria and antibiotic resistance situation among the patients. MethodsA retrospective study of the medical records of all patients undergoing arthroplasty from the Second Xiangya Hospital of Central South University from 2014 to 2018, 40 patients with periprosthetic joint infection, 37 patients with aseptic loosening and 59 patients with extra-articular infection were selected. The results of serum D-dimer, C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) were collected. As well as the bacterial types and antimicrobial susceptibility test results from tissue or joint fluid samples around the prosthetic joint of the patients were collected. All the relevant data were analyzed. ResultsThe serum D-dimer, CRP and ESR level were significantly higher in the patients with PJI. The mean D-dimer level was 2.0795 μg/mL in PJI group compared with 0.6854 μg/mL in aseptic loosening group (p = 0.000) and 0.4556 μg/mL in extra-articular infection group (p = 0.000). For diagnosing PJI, the serum D-dimer test demonstrated better sensitivity (87.50%), and better specificity (89.19%); while the serum CRP and ESR had a sensitivity of 80.00% and 82.50% and a specificity of 78.38% and 64.86%, respectively. Moreover, the sensitivity and specificity of ESR and CRP combined was 75.00% and 83.78%, respectively. In addition, 29 strains of pathogens around the prosthesis after arthroplasty were detected, including 22 strains of Gram-positive bacteria, 3 strains of Gram-negative bacteria, and 4 strains of fungi. The staphylococcus was the major pathogen showing high resistance to Cefoxitin and ampicillin. ConclusionPatients with PJI have high levels of serum D-dimer, which is a promising marker for the diagnosis of PJI. The Gram-positive bacteria are major pathogen in PJI after arthroplasty, and Staphylococcus aureus is the most common organism. Clinical efficacy is significantly improved by reasonable choice of antibiotics and effective medicine education.

ARTICLE WITHDRAWN] The Distribution of Pathogenic Bacteria and Risk Factors for Postoperative Infection in Tibial Fracture Patients Receiving Double-Plate Fixation

This article has been withdrawn at the request of the publisher in December 2020.

Characteristics and Influencing Factors of Pathogenic Bacteria in Lung Cancer Chemotherapy Combined with Nosocomial Pulmonary Infection

背景与目的本研究旨在探讨肺癌患者化疗期间并发院内肺部感染的病原菌类型、分布、耐药性及影响因素。方法本研究回顾性分析2017年1月-2018年12月于浙江大学医学院附属第一医院住院治疗的411例肺癌化疗患者的临床资料，统计患者院内肺部感染发生率、病原体、耐药性及影响因素。结果411例肺癌患者在化疗期间发生院内肺部感染184例次，感染率达44.77%，分离的病原体包括革兰阴性菌、革兰阳性菌、病毒、真菌和结核，其中以革兰阴性菌为主，占37.25%，其次为病毒感染，占15.69%。革兰阴性菌以铜绿假单胞菌和肺炎克雷伯菌为主，革兰阳性菌以金黄色葡萄球菌和肺炎链球菌常见，病毒以乙型流感病毒为主，真菌以念珠菌和曲霉菌多见。铜绿假单胞菌对亚胺培南的耐药率偏高，达26.67%，而肺炎克雷伯菌对亚胺培南的耐药率仍保持低水平，为12.50%；主要革兰阳性菌对万古霉素的耐药率均为0.00%。低蛋白血症、化疗周期长、高强度化疗及合并有慢性阻塞性肺疾病、支气管扩张基础疾病者是肺癌患者在化疗期间合并院内肺部感染的高危因素（P < 0.05）。结论肺癌患者化疗期间合并院内肺部感染的病原菌分布和耐药性具有一定的特征，临床医生应加强对病原菌及其耐药性检测，在对症治疗的基础上，以达到保障治疗效果、延长患者生存期的目的，对高危患者应做好预防措施，尽可能降低化疗周期及强度，以减少感染的发生。