Differences in immune damage between patients with severe fever with thrombocytopenia syndrome and patients with tsutsugamushi disease / 中华危重病急救医学

Objective:To analyze the difference of immune damage between patients with severe fever with thrombocytopenia syndrome (SFTS) and patients with tsutsugamushi disease.Methods:A prospective case-control study was conducted. Thirty-one patients with SFTS and 16 patients with tsutsugamushi disease admitted to the First Affiliated Hospital of Anhui Medical University from October 2014 to June 2017 were enrolled, and another 10 healthy people were enrolled as control. The counts of CD4 + and CD8 + T lymphocytes, and the proportion of CD3 + T lymphocytes, natural kill cells (NK cells), B lymphocytes and plasma cells were detected by flow cytometry. Thirty-four inflammatory mediators were determined by a multiplex Luminex? system synchronously. The differences of lymphocytes and cytokines between the two groups were compared. Results:The proportion of CD3 + T lymphocytes, the counts of CD4 + and CD8 + T lymphocytes in SFTS patients were significantly lower than those in patients with tsutsugamushi disease ( t values were 4.860, 9.411 and 5.030, respectively, all P < 0.01), and the proportion of NK cells and B lymphocytes were significantly higher than those in patients with tsutsugamushi disease ( t values were 2.344 and 5.896, respectively, both P < 0.05). The proportion of plasma cells in peripheral blood of SFTS patients was (7.7±1.2)%, the highest proportion of plasma cells in severe SFTS patients was up to 30%, and all patients showed λ monoclonal cell group in plasma cells. No plasma cells were detected in tsutsugamushi disease patients. The abnormal expressions of interleukin-1 receptor antibody (IL-1RA), interleukin (IL-6, IL-15, IL-10, IL-8), tumor necrosis factor-α (TNF-α), γ-interferon (IFN-γ), granulocyte colony-stimulating factor (G-CSF), eosinophil chemotactic factor (Eotaxin), IFN-γ-inducible protein-10 (IP-10), monocyte chemoattractant protein-1 (MCP-1), macrophage inflammatory protein (MIP-1α, MIP-1β), platelet-derived growth factor (PDGF-AA, PDGF-AB/BB), activated regulatory normal T cells and secretion factors (RANTES) were found in patients with SFTS and tsutsugamushi disease. The levels of IL-1RA, IL-6, IL-15, IL-10, TNF-α, IFN-γ, G-CSF, Eotaxin, IL-8, IP-10, MCP-1 and MIP-1α in SFTS patients were significantly higher than those in patients with tsutsugamushi disease ( Z values were 2.312, 2.447, 3.660, 5.444, 1.965, 2.402, 2.402, 2.997, 3.525, 2.481, 3.817, and 2.211, respectively, all P < 0.05), while PDGF-AA, PDGF-AB/BB and RANTES were significantly lower than those in patients with tsutsugamushi disease ( Z values were 3.728, 2.514, 2.649, respectively, all P < 0.05). Correlation analysis showed that RANTES, PDGF-AA and PDGF-AB/BB levels were significantly positively correlated with the level of platelet in patients with SFTS and tsutsugamushi disease (SFTS: r values were 0.223, 0.365, 0.330; tsutsugamushi disease: r values were 0.263, 0.632, 0.407, respectively, all P < 0.05). In SFTS patients, compared with the survival group ( n = 21), the CD3 + and CD4 + T lymphocytes in the death group ( n = 10) significantly decreased, while the plasma cells significantly increased ( t values were 3.980, 3.314 and 26.692, respectively, all P < 0.01); IL-1RA, IL-6, IL-15, IL-10, TNF-α, IFN-γ, G-CSF, Eotaxin, IL-8, IP-10, MCP-1, MIP-1α and MIP-1β significantly increased, while PDGF-AA, PDGF-AB/BB and RANTES significantly decreased ( Z values were 3.930, 4.014, 2.832, 3.592, 2.958, 3.508, 2.578, 3.254, 4.270, 3.465, 2.663, 3.085, 3.107, 3.639, 3.043 and 3.825, respectively, all P < 0.05). Conclusions:The immune function was impaired more seriously in SFTS patients than that in tsutsugamushi disease patients. Excessive humoral immunity and apoptosis of T lymphocytes are closely related to the death in SFTS patients. The detection of CD4 cells, plasma cells and proinflammatory and anti-inflammatory cytokines (e.g. IL-6, IL-10) had great clinical significance for the differentiation and illness evaluation in disease with SFTS or tsutsugamushi disease.

Differences of clinical manifestations and organ damage between patients with severe fever with thrombocytopenia syndrome and patients with tsutsugamushi disease / 中华传染病杂志

Objective To analyze the differences of clinical manifestations and organ damage between patients with severe fever with thrombocytopenia syndrome(SFTS)and patients with tsutsugamushi disease,and to investigate the prognostic factors of SFTS.Methods The research was performed on 49 patients with SFTS and 16 patients with tsutsugamushi disease who visited the First Affiliated Hospital of Anhui Medical University from October 2014 to June 2017.The general information of patients including region,age,gender and clinical manifestations were evaluated.Blood routine,liver and kidney function,myocardial enzyme levels,lipase,amylase,electrolytes,C-reactive protein,procalcitonin,prothrombin time(PT)and activated partial thromboplastin time(APTT)were continuously monitored during the course of disease.T test was used for continuous variables of normal distribution,and non-parametric test was used for variables of non-normal distribution.Chi-square test was used for categorical variables.Results The mean age of SFTS patients was 62.1±15.5(ranging from 17 to 87 years)and the mean age of tsutsugamushi patients was 56.1±9.2(ranging from 47 to 73 years).There was no significant difference between the two groups(t=1.47,P=0.147).There were 25 males(51%)in SFTS patients and 8 males(50%)in tsutsugamushi disease patients.There was no significant difference between the two groups(x2=0.005,P=0.943).The incidences of headache,vomiting,superficial lymphadenectasis,disturbance of consciousness,proteinuria,hematuria,pulmonary infection,multiple organ dysfunction and acute pancreatitis in SFTS patients were all significantly higher than those in tsutsugamushi disease patients(x2=8.82,4.38,8.71,11.17,7.88,5.56,4.35,9.43,and 8.13,respectively,P <0.05 or 0.01).The counts of leukocytes(Z=2.73),neutrophils(Z=2.46),lymphocytes(Z=3.15),platelets(Z=4.25),albumin(Z=2.65)and sodium ion(t=2.10)in SFTS patients were all significantly lower than those in patients with tsutsugamushi disease(P <0.05 or 0.01).The levels of aspartate aminotransferase(Z=2.94),lactate dehydrogenase(Z=3.42),creatine kinase(CK)(Z=2.88),amylase(Z=2.11),lipase(Z=2.82),creatinine(Z=2.07)and urea nitrogen(Z=2.50)in fatal SFTS patients were all significantly higher than those in patients with tsutsugamushi disease(P <0.05 or 0.01).Among 49 SFTS patients,16 patients died and 33 patients recovered finally.The age(t=3.33),platelet count(Z=2.55),alanine aminotransferase(ALT)(Z=2.10),aspartate aminotransferase(AST)(Z=2.22),lactate dehydrogenase(Z=2.26),CK(Z=3.50),CK-MB(Z=3.10),creatinine(Z=2.17),urea nitrogen(Z=2.36),and sodium(t=2.65)between the two subgroups had significant differences(P <0.05 or 0.01).Conclusions SFTS is more severe and has high mortality,while tsutsugamushi disease has a better prognosis.Early differential diagnosis and early rational treatment are important to reduce the mortality of patients with SFTS.

Characterization of Extended-Spectrum β-Lactamase Genes of Shigella flexneri Isolates With Fosfomycin Resistance From Patients in China

BACKGROUND: The emergence of fosfomycin resistance and extended-spectrum β-lactamase (ESBL) genes is a serious threat to public health and a new challenge in shigellosis treatment. The purpose of this study was to identify fosfomycin resistance and characterize β-lactamase genes in fos-carrying isolates of Shigella flexneri from patients in China. METHODS: A total of 263 S. flexneri isolates were collected from 34 hospitals in the Anhui Province of China during September 2012-September 2015 and screened for fosA3, fosA, and fosC2 by PCR amplification and sequencing. The fos-carrying isolates were then screened for β-lactamase genes. The clonal relationships between fosA3-carrying isolates, the transmissibility of fosfomycin resistance, replicon types of plasmids carrying fosfomycin resistance genes and other associated resistance genes were investigated. RESULTS: Twenty-five of the 263 isolates (9.5%) showed resistance to fosfomycin, and 18 (6.8%) were positive for fosA3. None of the isolates was positive for fosA or fosC2. Seventeen of the isolates carrying fosA3 (94%) were CTX-M producers (seven CTX-M-55, five CTX-M-14, and five CTX-M-123), while three (16.7%) were TEM producers (TEM-1).Sixteen (88.9%) fosA3-carrying isolates exhibited multi-drug resistance. The replicon types of the 13 fosA3-carrying plasmids were IncF (n=13), IncHI2 (n=3), IncIl-Ir (n=2), and IncN (n=1). CONCLUSIONS: Our results indicated that fosA3 could spread through plasmids in S. flexneri isolates, along with the bla(CTX-M) and bla(TEM), which facilitate its quick dispersal. To the best of our knowledge, this is the first report of CTX-M-123-type ESBLs in S. flexneri isolates from patients in China.

The profile of antibiotic resistantpathogens isolated from ascites fluid patients in intensive care unit during past 12 years / 中华危重病急救医学

Objective To investigate the profile and antibiotic resistance of bacteria in patients with ascites infection in intensive care unit (ICU) patients in order to provide a reference for rational clinical use of antibiotics. Methods A retrospective analysis was conducted. The bacteria isolated from ascetic fluid patients admitted from January 1st, 2004 to October 31st, 2015 to ICU of the First Affiliated Hospital of Anhui Medical University were identified, and their susceptibility to antibiotics was analyzed. Patients, who were admitted from January 1st, 2004 to December 31st, 2009 were assigned to group A, and patients admitted afterwards were assigned to group B. Results A total of 637 specimens of ascetic fluid were examined, with 185 positive culture (29.0%) during the 12 years, and 203 strains of bacteria were found. Among them 126 strains (62.1%) of gram-negative bacteria (G-), 54 (26.6%) of gram-positive bacteria (G+) and 23 (11.3%) strains of fungi were found. Compared the result of group B with that of group A, the proportion of G- bacteria was increased [71.2% (99/139) vs. 44.2% (27/64)], and that of G+ decreased [17.3% (24/139) vs. 46.9% (30/64)] in group B. The difference was statistically significant (χ2 = 20.34, P = 0.001). The main pathogenic bacteria were G-, and Enterobacteriaceae was the most common pathogenic bacteria in intra-abdominal infection of ICU patients. The isolation rate of Escherichia coli and Klebsiella pneumoniae(35.7%, 10.3%) ranked in the first and third in G- bacteria, respectively. The resistant rate of Escherichia coli against penicillin and third generation cephalosporin were > 95.0% and > 73.3%, and it showed a sensitive rate of 70% to β-lactam/inhibitor, amikacin and minocycline, and a higher sensitivity to carbapenems and tigecycline (11.1%, 0). Forty-eight strains of non-fermentation bacteria were found with a rate of 23.7%. The positive rates of Acinetobacter baumannii in groups A and B were 7.8% (5/64) and 23.7% (33/139), respectively, and they ranked first among non-fermentation bacteria. Twenty strains (62.5%) multidrug-resistant Acinetobacter baumannii were found. Acinetobacter baumannii showed a resistance rate of 84.6% to cefoperazone/sulbactam, 35.3% to minocycline, and 53.3% to tigecycline. Candida albicans was the most commonly isolated fungus in intra-abdominal infections (87.5%). No strains resistant to common antifungal drugs were isolated. Conclusions G- bacteria was the main pathogen in intra-abdominal infection in patients with ascites. Non-fermenters showed an increasing trend of producing infection, and the proportion of multidrug-resistant Acinetobacter baumannii infection increased year by year, and more attention should be taken by attending doctors.

Discovery of a Fluoroquinolone-Resistant Serratia marcescens Clinical Isolate without Quinolone Resistance-Determining Region Mutations

No abstract available.

Surveillance of Antimicrobial Susceptibility Patterns among Shigella Species Isolated in China during the 7-Year Period of 2005-2011

BACKGROUND: Shigella is a frequent cause of bacterial dysentery in the developing world. Treatment with antibiotics is recommended for shigellosis, but the options are limited due to globally emerging resistance. This study was conducted to determine the frequency and pattern of antimicrobial susceptibility of Shigella in China. METHODS: We studied the antimicrobial resistance profiles of 308 Shigella spp. strains (260 S. flexneri, 40 S. sonnei, 5 S. boydii, and 3 S. dysenteriae) isolated from fecal samples of patients (age, from 3 months to 92 yr) presenting with diarrhea in different districts of Anhui, China. The antimicrobial resistance of strains was determined by the agar dilution method according to the CSLI guidelines. RESULTS: The most common serogroup in the Shigella isolates was S. flexneri (n=260, 84.4%), followed by S. sonnei (n=40, 13.0%). The highest resistance rate was found for nalidixic acid (96.4%), followed by ampicillin (93.2%), tetracycline (90.9%), and trimethoprim/sulfamethoxazole (80.8%). Among the isolates tested, 280 (91.0%) were multidrug resistant (resistant to > or =2 agents). The most common resistance pattern was the combination of ampicillin, tetracycline, and trimethoprim/sulfamethoxazole (70.8%). Resistance to ampicillin and tetracycline were more common among S. flexneri than among S. sonnei isolates. CONCLUSIONS: S. flexneri is predominant in Anhui, China, and its higher antimicrobial resistance rate compared with that of S. sonnei is a cause for concern. Continuous monitoring of resistance patterns is necessary to control the spread of resistance in Shigella. The recommendations for antimicrobial treatment must be updated regularly based on surveillance results.

Study of plasmid-mediated quinolone resistance determinants in Citrobacter freundii / 中华传染病杂志

Objectives This study was conducted to detect and analyze the presence of plasmidmediated quinolone resistance (PMQR) determinants [qnr,aac-(6′)-Ib-cr and qepA] among clinical isolates of Citrobacter freundii strains isolated from patients in Anhui,China,and to understand the susceptibility of PMQR positive strains to commonly used antimicrobial agents.Methods During the year 2009,31 Citrobacter strains were collected from the First Affiliated Hospital of Anhui Medical University.Polymerase chain reaction (PCR) was used to detect PMQR genes.Amplicons were purified,sequenced and compared with data from the GenBank.Conjugation experiments were conducted to determine whether the qnr-carrying plasmids were self-transferable.The susceptibility of the positive isolates and transconjugants were tested by agar dilution method according to Clinical and Laboratory Standards Institute (CLSI) guidelines.The minimum inhibitory concentrations (MIC) of ciprofloxacin and levofloxacin were determined by E-test strips.Results Among the 31 Citrobacter strains,the qnr genes were detected in 8 isolates (25.8％),among which,6 carried qnrB.Aac-(6′)-Ib-cr and qepA were not identified in these isolates.The qnr genes were transferred from four clinical isolates to their transconjugants.Sequence analysis identified one novel qnrB variant (qnrB24).The resistant rate of qnr-positive clinical isolates to quinolone was 87.5 ％.Most of them were also resistant to various other antibiotics,including cefotaxime (75.0 ％),amikacin (7.5 ％),ceftazidime (62.5 ％),cefapime (37.5 ％),and gentamycin (87.5 ％).All qnr positive strains were susceptible to imipenem.MIC of all transconjugants showed reduced susceptibility to fluoroquinolones,with MIC increased by 10-23 folds.Conclusions Our study shows that qnr gene has occurred in Citrobacter freundii isolates from Anhui Province,China.QnrB is most prevalent in these isolates.Most qnr positive isolates are resistant to commonly used antimicrobial agents.

Distribution and resistance surveillance of 104 clinical strains of Serratia marcescens in Anhui Province / 中华传染病杂志

ObjectiveTo analyze the clinical distribution and antimicrobial resistance profile of Serratia marcescens(S. marcescens), and to provide the scientific evidence supporting clinical diagnosis and treatment.MethodsThe antimicrobial susceptibility test was performed in 104 strains of S. marcescens by agar dilution method. The results were judged according to the criteria recommended by Clinical and Laboratory Standards Institute (CLSI) 2010.The data were analyzed by chi square test. Results The majority of S. marcescens were isolated from sputum specimens,accounting for 59.6％ (62/104). The bacteria were most frequently isolated from department of respiratory (33.7％,35/104),followed by intensive care unit (23.1％,24/104),department of gerontology (16.3％, 17/104). The results of antimicrobial susceptibility test showed that the resistance rates of S.marcescens against ampicillin,gentamicin and cephazolin were high,which were 90.4％,86.5％ and 79.8％,respectively; those against the 3rd generation of cephalosporins were 24.0％-43.3％. No imipenem and meropenem resistant strains were identified. Compared with cefoxitin-resistant strains,the resistance rates of non-cefoxitin resistant strains against piperacillin (82.9％ vs 28.6％),ceftazidime (63.4％ vs 9.5％),aztreonam (68.3％ vs 9.5％),amikacin (68.3％ vs 20.6％),ciprofloxacin (48.8％ vs 19.1％) and chloramphenicol (90.3％ vs 58.7％) were all lower (all P ＜ 0.05 ). Conclusions S. marcescens is one of the most common conditional pathogenic bacteria leading to nosocomial infections,which is resistant to many kinds of antimicrobial agents.The surveillance of antimicrobial resistance in S. marcescens should be strengthened for purpose of preventing the transmission of multidrug resistant strains.

Chromosome and plasmid-mediated quinolone resistance mechanism in clinical isolates of Serratia marcescens / 中华检验医学杂志

Objective To investigate the prevalence of plasmid-mediated quinolone resistance ( PMQR ) determinants [ qnr,aac ( 6' ) -Ib-cr and qepA ]and mutations in quinolone resistance-determining regions (QRDRs) of gyrA and parC and their association with fluoroquinolone susceptibility in clinical isolates of Serratia marcescens in Anhui.Methods The minimum inhibition concentration ( MIC ) of 104 strains of S.rnarcescens collected from various clinical specimens from 34 hospitals during 2005 to 2010 were determined by agar dilution method.The qnr,aac (6')-Ib,qepA,gyrA and parC genes were screened by polymerase chain reaction (PCR) in 31 strains resistant to ciprofloxacin,and positive results were subsequently confirmed by sequencing.The conjugation experiments were performed for qnr and aac(6')-Ib-cr positive strains.The MIC of S.marcescens isolates,recipient strains and conjugants were tested by agar dilution method for quinolones and other antimicrobial agents.Results Six strains of the 31 S.marcescens isolates harboured qnr and/or aac(6')-Ib-cr genes.Among those 6 strains,2 strains harboured a qnrB6 gene,1 harboured a qnrS2 gene,and 4 harboured aac( 6' ) -Ib-cr,whereas no qnrA-,qnrC- or qnrD-positive isolate was detected.None of the 31 isolates carried the qepA gene.Mutations in the QRDR of gyrA and parC genes were detected in 9 and 7 isolates,respectively.The conjugation experiments were successfully carried out in 5 isolates of 6 PMQR determinants-postive strains.The MIC of conjugants for quinolones were increased evidently compared to recipient strains.Conclusions Chromosome and plasmid-mediated resistance determinants play an important role in quinolone resistance in clinical isolates of S.marcescens.And more important is that the PMQR determinants can be horizontal transmitted.It is necessary to continuously survey and watch for the spread of PMQR in S.marcescens in public health control program.

Detection of genotypes of plasmid-mediated quinolone resistance in clinical isolates of Shigella / 中华传染病杂志

ObjectiveTo investigate the variations and distributions of the plasmid-mediated quinolone resistance genes in clinical isolates of Shigella and their resistance to antimicrobial agents. Methodsqnr, aac(6')-Ib-cr and qepA genes were identified by polymerase chain reaction (PCR) in 137 clinical isolates of Shigella.DNA sequencing of gene-positive strains were analyzed and the conjugation experiment was performed. The minimal inhibitory concentrations (MIC) of Shigella isolates, recipient strains and transconjugants were tested by agar dilution method for quinolones and other antimicrobial agents. The genotype of transconjugants were determined by PCR and sequencing. ResultsFour (2.9％) strains of the 137 Shigella isolates were qnr gene positive, including 3 qnrS2 positive and 1 qnrB4 positive (GenBank accession numbers of the complete sequence were JF261185 and HQ917003, respectively).Furthermore,five (3.6％) aac ( 6')-Ib-cr gene-positive strains (GenBank accession number JF261186 ) and one (0.7％) qepA gene-positive strain were identified in all isolates. The conjugation experiments were successfully carried out in six out of ten PCR-positive isolates. The MIC of transconjugants against quinolones and other antimicrobial agents increased differently compared to recipient strains. Conclusions The plasmid-mediated quinolone resistance genes are lowly prevalent in clinical isolates of Shigella. However, these resistance genes have the characteristic of horizontal transfer, which indicates that more attention should be paid to this phenomenon.

Detection of hepatitis B virus DNA integration in hepatocellular carcinoma using hepatitis B virus-Alu-polymerase chain reaction / 中华传染病杂志

Objective To detect the integration of hepatitis B virus (HBV) DNA in HBVrelated human hepatocellular carcinomas (HCC). Methods Extracted DNA from the liver tissue samples and amplified by nested polymerase chain reaction (PCR) with specially designed U-base primers. According to the known genes and human Alu repeat sequences (Alu repeat) , primers were designed respectively. Integrated clones combined target HBV DNA and the adjacent cell gene sequences were established by PCR and products were sequenced by biotechnology companies.Accurate locations of HBV genes integrated in the human genomes were analyzed by national center for biotechnology information (NCBI) basic local alignment search tool (BLAST) and Map Viewer search. Results In 24 HBsAg positive HCC samples, 15 cases showed the integrations of HBV fragment. And the other 8 samples didn't show any evidence of integration. Among 14 samples with integration, forward insertions of HBV DNA into the host chromosomal DNA were found in 10 samples and reverse insertions were found in 8 samples while both forward and reverse insertions were found in 5 samples. Analysis from viral-cellular junctions suggested that the integrations were all happened with truncated viral DNA and could be in any locus of X gene. Conclusion HBV DNA integration is not distributed evenly throughout the host genome.

Distribution and Resistance to Antibiotics of Shigella in Anhui Province / 中华医院感染学杂志

OBJECTIVE To investigate the distribution and the resistance rate of Shigella in Anhui Province to guide the choice of antibacterials. METHODS Ninety one strains of Shigella were cultured in Sep 2005.The groups were identified by biochemical and serologic tests.Susceptibility of 91 strains of Shigella in Anhui to various antibiotics was tested using standardized custom dilution MIC panels according to CLSI(2005) guidelines. RESULTS There were 57 strains of Shigella flexneri,31 strains of S.sonnei and 2 strains ofS.boydii among 91 strains of Shigella.The resistance rates of Shigella to cefoperazone/sulbactam and piperacillin/tazobactam were remarkably lower than to other third generation cephalosporins.The susceptible rates to carbopenems were 100%.The resistance rates to ciprofloxacin lactate and pazufloxacin mesilate were 27.47% and 32.97%,respectively. CONCLUSIONS There is a certain resistance rate of the Shigella to fluoroquinolones and the third generation cephalosporins.More attention should be paid to the surveillance and control of such resistance.