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BACKGROUND@#Lung cancer is the highest incidence of cancer in the world, which seriously threatens human health. Early diagnosis and treatment of lung cancer is particularly important for the survival of lung cancer patients. Serum tumor markers have been widely used as an important method for early diagnosis of tumor. However, there are few early diagnostic markers for lung cancer. Therefore, the aim of this study was to investigate the expression level of Lipocalin-2 and its clinical significance in serum of patients with lung cancer.@*METHODS@#The serum levels of Lipocalin-2 in 60 lung cancer patients and 63 healthy people were detected by enzyme-linked immunosorbent assay (ELISA), and the relationship between the expression level of Lipocalin-2 and the clinical characteristics of lung cancer was analyzed.@*RESULTS@#The expression level of Lipocalin-2 in peripheral blood serum of patients with lung cancer was significantly higher than that of healthy people, and the difference was statistically significant (P<0.001). The expression of Lipocalin-2 in patients with lung cancer was related to the differentiation, stage and lymph node metastasis of pathological tissues, and the difference was statistically significant (P<0.05). The expression level of Lipocalin-2 in serum of patients with poorly differentiated lung cancer was higher than that of patients with well differentiated lung cancer; the expression level of Lipocalin-2 in serum of patients with lymph node metastasis was higher than that of patients without lymph node metastasis; the expression level of Lipocalin-2 in patients with clinical stage III + IV lung cancer was significantly higher than that of patients with clinical stage I + II lung cancer, and the differences were statistically significant (P<0.05).@*CONCLUSIONS@#Lipocalin-2 is highly expressed in serum of patients with lung cancer, which is related to pathological differentiation, stage and lymph node metastasis. It is expected to become a potential new tumor marker for clinical diagnosis of lung cancer.
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Objective:To monitor the susceptibility of common used antimicrobial agents against nosocomial Gram-negative bacilli in 2018 across China.Methods:Prospective collection of Gram-negative bacilli from 13 teaching hospitals nationwide from January to December 2018. The minimal inhibitory concentration (MICs) of antibiotics such as meropenem was determined by agar dilution methods and broth microdilution methods. Interpretation of results using the Clinical and Laboratory Standards Institute(CLSI) 2019 M100S (29th Edition) standard. Data were analyzed by using WHONET-5.6 software.Results:A total of 1 214 non-repetitive Gram-negative bacilli were collected, accounting for 96.7% (1 174/1 214) of blood and sterile body fluid samples. The activity of antimicrobial agents against 871 strains of Enterobacteriaceae was as follows in descending order of susceptible rate: amikacin (93.2%, 812/871), meropenem (92.0%, 801/871), ertapenem (88.9%, 774/871), imipenem (88.4%, 770/871), piperacillin-tazobactam (84.0%, 732/871), cefoperazone-sulbactam (83.1%, 724/871), cefepime (71.4%, 622/871), minocyline (68.9%, 600/871), ceftazidime (66.9%, 583/871), levofloxacin (54.4%, 474/871).The resistance rates of Escherichia coli to the third generation cephalosporins were 61.5% (155/252) (ceftriaxone) and 60.7% (153/252) (cefotaxime), respectively. The resistance rates of Klebsiella pneumoniae to the third generation cephalosporins were 56.6% (126/222) (ceftriaxone) and 57.9% (129/222) (cefotaxime), respectively. The incidence of extended-spectrum β lactamase (ESBLs) positive E. coli and K. pneumoniae was 50.2% (127/252) and 18.2% (40/222), respectively. Over 95% of all the ESBLs positive strains were susceptible to imipenem and meropenem. The incidence of carbapenem-resistant Escherichia coli and Klebsiella pneumoniae was 2.8% (7/252) and 20.4% (45/222), respectively. For Enterobacter cloacae, Klebsiella aerogenes, Citrobacter freundii, the most susceptible agent were tigecycline (96.3%-100%), followed by amikacin (94.9%-97.1%), meropenem (89.8%-96.6%)and imipenem (89.8%-94.9%).The susceptibility of Proteus mirabilis, Morganella morganii and Serratia marcescens to meropenem and amikacin was over 90%.A total of 67 strains of carbapenems resistant enterobacteriaceae(CRE) were detected. Modified carbapenem inactivation method showed, 45 strains were serine carbapenemase and 20 were metalloenzymes. The susceptibility of Pseudomonas aeruginosa to meropenem and imipenem were 73.2% (112/153) and 66.0% (101/153), respectively. Acinobacter baumannii has the highest sensitivity to colistin (100%, 163/163), followed by tigecycline (87.1%, 142/163).Compared with other sources of infection, specimens of bloodstream infections were less resistant to Klebsiella pneumoniae (17.6%, 27/153 vs 21.7%, 15/69) and Acinetobacter baumannii (68.3%, 71/104 vs 71.2%, 42/59). Escherichia coli (2.5%,4/198 vs 0%,0/54) and Pseudomonas aeruginosa (37%, 33/89 vs 18.8%, 12/64) have a high proportion of carbapenem resistance. Conclusions:Carbapenems still maintain high antibacterial activity against Enterobacteriaceae bacteria, especially strains producing only ESBLs. Carbapenem-resistant Klebsiella pneumoniae should be given sufficient attention. Carbapenemase is the most important drug resistance mechanism of carbapenem-resistant Enterobacteriaceae in China.
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Objective:To investigate risk factors for infection of biofilm-forming Klebsiella pneumonia and prognosis of patients. Methods:The clinical data of 125 patients with Klebsiella pneumoniae bloodstream infection admitted in Tianjin Medical University General Hospital from January to December 2019 were analyzed retrospectively. According to the presence of Klebsiella pneumoniae biofilm, patients were divided into biofilm positive group ( n=81) and biofim negative group ( n=44). In biofilm positive group 17 patients died (fatal group) and 64 survived (survival group) during 3-month follow-up. The antimicrobial resistance of the strains was analyzed, and multivariate logistic regression analysis was used to investigate the risk factors of biofilm-forming Klebsiella pneumoniae infection and the risk factors of death in biofilm positive group. Results:A total of 125 strains of Klebsiella pneumoniae were isolated from 125 patients, of which 81(64.80%) strains were biofilm positive. Antimicrobial resistance analysis showed that the resistance rate of biofilm positive group to aztreonam, amikacin, ciprofloxacin and levofloxacin was significantly higher than that in the biofilm negative group ( χ2=5.94, 4.03, 5.05 and 4.15, P<0.05). Multivariate logistic regression analysis showed that endotracheal intubation ( OR=3.460, 95% CI 2.890-14.445, P<0.05) and administration of immunosuppressants ( OR=6.945, 95% CI 1.160-21.567, P<0.05) within 3 months before infection were independent risk factors for biofilm-forming Klebsiella pneumoniae bloodstream infection. The use of tegacycline ( OR=4.886, 95% CI 1.123-21.263, P<0.05) within 3 months before death was independent risk factors for the death of biofilm-positive Klebsiella pneumoniae bloodstream infection. Conclusions:In order to reduce the incidence and fatality of biofilm-forming Klebsiella pneumoniae bloodstream infection, antibiotics should be used rationally and invasive procedures should be minimized.
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Objective@#To study the mechanism of lncRNA-mtb in Mycobacterium tuberculosis (M.tuberculosis)-infected macrophages.@*Methods@#A predicting software and Western blot assay were used to verify the non-coding nature of lncRNA-mtb. RT-qPCR was performed to detect lncRNA-mtb expression in macrophages infected by different Mycobacteria. Cytokine secretion was detected with ELISA after silencing the expression of lncRNA-mtb in macrophages with RNA interference (RNAi) technology. Western blot and RT-qPCR were performed to analyze whether the activation of macrophage inflammation could be induced by lncRNA-mtb during M. tuberculosis infection. Effects of lncRNA-mtb silencing on the bactericidal activity of M. tuberculosis-infected macrophages were evaluated.@*Results@#Increased expression of lncRNA-mtb was observed in macrophages infected with M. tuberculosis H37Rv or H37Ra. After silencing the expression of lncRNA-mtb, IL-1β secretion in H37Rv infected-macrophages was significantly decreased. Further studies revealed that lncRNA-mtb might be involved in the activation of NLRP3 in M. tuberculosis-infected macrophages. The bactericidal activity of macrophages against H37Ra was impaired after silencing the expression of lncRNA-mtb.@*Conclusions@#Enhanced expression of lncRNA-mtb could be induced in macrophages infected with H37Rv or H37Ra. Moreover, lncRNA-mtb was involved in M. tuberculosis-induced inflammation in cells. Silencing lncRNA-mtb wolud attenuate the ability of macrophages to clear M. tuberculosis.
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Objective@#To observe the species distribution, clinical features, efficacy and safety of anti-fungus therapy in advanced elderly patients with fungemia.@*Methods@#Clinical data of patients aged 70 years and over with fungemia admitted into geriatric intensive care unit (GICU) of our hospital from Nov. 2012 to Nov. 2017 were retrospectively analyzed. The specie distribution, liver toxicity, differences in biochemical liver and renal functions before and after 28 days of treatment between the caspofungin group and the azole group (fluconazole plus voriconazole), and 28-d survival rate and its risk factors for death were analyzed.@*Results@#A total of 72 patients were enrolled, with a median age of 85.5 years (83, 90), a median score of Acute Physiology and Chronic Health Enquiry (APACHE-Ⅱ) of 25.5 (20.3, 31.5), a median score of Sequential Organ Failure Assessment (SOFA) 7 (4.0, 9.8). There were 33 patients (45.8%) with diabetes, 2 patients (2.8%) with hematological diseases, 44 patients (61.1%) with solid tumors and 18 patients (25.0%) with renal insufficiency. Thirty patients (41.7%) needed mechanical ventilation. The detection rate of Candida parapsilosis was 73.6% (53 cases), Candida famata 9.7% (7 cases), Candida tropicalis 5.6% (4 cases), Candida albicans 2.8% (2 cases), Candida glabrata 2.8% (2 cases) and others 5.6% (4 cases). The incidence rate of total liver toxicity was 23.6% after anti-fungus treatment. After 28 days of treatment, 29 patients survived in the caspofungin group (n=42) and 16 patients survived in the azole group (n=30). There were no significant differences in liver and renal function between the two groups before and after treatment. Logistic regression analysis showed that solid tumors (OR: 19.904, 95%CI: 1.944-203.808) and the median APACHE Ⅱ score were the independent risk factors for 28-day death in advanced patients with fungemia.@*Conclusions@#Fungemia is becoming more and more prominent in the GICU, which requires clinician’s constant attention in order to provide more basis for the treatment of fungemia in elderly patients.
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Objective To observe the species distribution,clinical features,efficacy and safety of anti-fungus therapy in advanced elderly patients with fungemia.Methods Clinical data of patients aged 70 years and over with fungemia admitted into geriatric intensive care unit (GICU) of our hospital from Nov.2012 to Nov.2017 were retrospectively analyzed.The specie distribution,liver toxicity,differences in biochemical liver and renal functions before and after 28 days of treatment between the easpofungin group and the azole group (fluconazole plus voriconazole),and 28-d survival rate and its risk factors for death were analyzed.Results A total of 72 patients were enrolled,with a median age of 85.5 years (83,90),a median score of Acute Physiology and Chronic Health Enquiry (APACHE-Ⅱ) of 25.5 (20.3,31.5),a median score of Sequential Organ Failure Assessment (SOFA) 7 (4.0,9.8).There were 33 patients (45.8％) with diabetes,2 patients (2.8％) with hematological diseases,44 patients (61.1％) with solid tumors and 18 patients (25.0％) with renal insufficiency.Thirty patients (41.7％) needed mechanical ventilation.The detection rate of Candida para psilosis was 73.6％ (53 cases),Candida famata 9.7％ (7 cases),Candida tropicalis 5.6％ (4 cases),Candida albicans 2.8％ (2 cases),Candida glabrata 2.8％ (2 cases) and others 5.6％ (4 cases).The incidence rate of total liver toxicity was 23.6％ after anti-fungus treatment.After 28 days of treatment,29 patients survived in the caspofungin group (n=42) and 16 patients survived in the azole group (n=30).There were no significant differences in liver and renal function between the two groups before and after treatment.Logistic regression analysis showed that solid tumors (OR:19.904,95％CI:1.944-203.808) and the median APACHE Ⅱ score were the independent risk factors for 28-day death in advanced patients with fungemia.Conclusions Fungemia is becoming more and more prominent in the GICU,which requires clinician's constant attention in order to provide more basis for the treatment of fungemia in elderly patients.
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Objective To investigate the spectrum and antimicrobial resistance of major pathogens causing nosocomial infections in China, 2016. Methods Non-duplicated nosocomial cases as well as pathogens causing bloodstream infections ( BSI) , hospital-acquired pneumonia ( HAP) and intra-abdominal infections ( IAI ) from 12 teaching hospitals across China were collected. The minimum inhibitory concentrations (MICs) of important clinical common strains were determined by agar dilution method or broth microdilution method. The CLSI M100-S27 criteria was used for interpretation. Data were analyzed by using WHONET-5. 6 software. Results A total of 2060 cases were collected, including 894 cases from BSI, 630 cases from HAP and 536 cases from IAI. The MICs of 1896 important clinical common strains were determined. Escherichia coli and Klebsiella pneumoniae were the most prevalent pathogens causing BSI and IAI, while Acinetobacter baumanii and Pseudomonas aeruginosa were dominated in HAP. All Staphylococcus aureus were susceptible to tigecycline, linezolid, daptomycin and glycopeptides. Methicillin-resistant S. aureus accounted for 44. 4％ ( 75/169 ) of all the S. aureus. The rate of methicillin-resistant coagulase-negative staphylococci was 80. 9％ ( 72/89 ) . No Enterococcus strains were found resistant to tigecycline, linezolid or daptomycin. Vacomycin resistant enterococcus was found in Enterococcus faecium, accounting for 1. 8％ ( 2/111 ) of all E. faecium strains. Tigecycline, meropenem, amikacin, imipenem, and polymyxin B exhibited high potency against Enterobacteriaceae and the susceptibility rates were 96. 6％(865/895), 94. 3％ (859/911), 94. 2％ (858/911), 94. 1％ (857/911), and 91. 6％ (820/895), respectively. The prevalence of extended-spectrum β-lactamase was 58. 4％ ( 263/450 ) in E. coli and 28. 6％ ( 84/294 ) in K. pneumonia. The rate of carbapenem resistant K. pneumonia and E. coli was 15. 3％ ( 45/294 ) and 1. 8％ ( 8/450 ) , respectively. The percentage of polymyxin B resistant K. pneumonia and E. coli was 4. 1％ ( 12/294 ) and 4. 4％ ( 20/450 ) , respectively. The rate of tigecycline resistant K. pneumonia and E. coli was 2. 4％ ( 7/294 ) and 0. 2％ ( 1/450 ) , respectively. A. baumanii showed low susceptibility to the antimicrobial agents except tigecycline ( 91. 4％, 235/257 ) and polymyxin B (100％, 257/257). The rate of carbapenem resistant A. baumanii was 80. 5％ (207/257). The rate of carbapenem resistant P. aeruginosa was 31. 7％ ( 59/186 ) . Polymyxin B and amikacin demonstrated high antibacterial activity against P. aeruginosa with susceptility rate of 100％ ( 186/186 ) and 90. 9％ ( 169/186), respectively. Conclusions Nosocomial pathogens showed high susceptibilities against tigecycline and polymyxin B. Antimicrobial resistance in A. baumannii is a serious problem. The prevalence of carbapenem-resistant Enterobacteriaceae and polymyxin B resistant Enterobacteriaceae has increased, which should be monitored continuously in China.
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Objective To screen high-affinity aptamers binding to the surface lipopolysaccharide (LPS) of Pseudomonas aeruginosa (PA), and to analyze their inhibitory effects on macrophage polarization. Methods LPS of PA was ectracted and purified. High-affinity aptamers binding to the LPS of PA were screened by systematic evolution of ligands by exponential enrichment (SELEX). Enzyme-linked oligonucleotide assay (ELONA) and quantitative PCR (Q-PCR) were performed to investigate their influences on macrophage polarization. Results In this study, an aptamer PL-6 that could specifically bind to PA-LPS was screened suc-cessfully and found to be able to block the binding of PA-LPS to the corresponding receptor TLR4, inhibit mac-rophage M1 polarization and maintain macrophage homeostasis. Conclusion This study found a high-affinity aptamer binding to the LPS of PA, which might provide a new strategy for the prevention and treatment of sepsis caused by PA.
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Objective To observe the clinical features of senile patients suffering from fungemia of Candida parapsilosis, and the effect and safety of antifungal therapy in treatment of this disease in geriatric intensive care unit (GICU). Methods The clinical data of patients with fungi positive either in peripheral blood culture or catheter culture admitted to the GICU of Tianjin Medical University General Hospital from November 2012 to June 2015 were retrospectively analyzed, of them 45 cases were of infection of Candida parapsilosis (parapsilosis group) and 15 cases infection of non-Candida parapsilosis (non-parapsilosis group). The clinical features of the two groups were collected, such as sex, age, acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ) score, sequential organ failure assessment (SOFA) score, timing of antifungal therapy, number of patients mechanical ventilation, concomitant disease, catheter-related infection, method of catheter-indwelling, levels of creatinine (Cr), hemoglobin (Hb), platelet count (PLT), albumin (ALB), alanine aminotransferase (ALT), aspartate aminotransferase (AST), etc.; the differences in above indicators were compared between the two groups; multifactor Cox-regression-analysis was used to analyze the risk factors that could affect the patients' prognosis; the patients' survival rates on 7, 14 and 28-day were calculated and compared between the two groups, and the therapeutic effects of different anti-fungal drugs on patients' survival rates and liver function damage were recorded and compared. Results The non-parapsilosis group had a higher rate in mechanical ventilation than parapsilosis group [73.3% (11/15) vs. 33.3% (15/45), P < 0.05], and in the comparisons of other clinical features, there were no statistical significant differences between the two groups (all P > 0.05). There were no statistical significant differences in survival rates in the duration of 7, 14 and 28 days between the two groups[7 days: 82.2% (37/45) vs. 66.7% (10/15), 14 days: 75.6% (34/45) vs. 60.0% (9/15), 28 days: 66.7% (30/45) vs. 46.7% (7/15), all P > 0.05]. When the patients in parapsilosis group treated with echinocinomycin were compared with those treated with azolol, no statistical significant differences were found between the 2 types of therapy in the survival rates in the duration of 7, 14, and 28 days after treatment [7 days: 100.0% (23/23) vs. 82.4% (14/17), 14 days: 91.3% (21/23) vs. 76.5% (13/17), 28 days: 78.3% (18/23) vs. 70.6% (12/17), all P > 0.05]. Multifactor Cox-regression-analyses showed:diabetes [odds ratio (OR) = 0.268, 95% confidence interval (95%CI) = 0.077 - 0.928, P = 0.038), infection of Candida parapsilosis (OR = 0.260, 95%CI = 0.072 - 0.946, P = 0.041), APACHE Ⅱ score (OR = 1.241, 95%CI = 1.051 - 1.466, P = 0.011) and SOFA score (OR = 1.405, 95%CI = 1.005 - 1.966, P = 0.047) were the risk factors affecting the prognosis of the patients. When the patients in parapsilosis group treated with echinocinomycin were compared with those treated with azolol, there were no statistical significant differences in incidences of aggravation of liver damage and newly developed liver damage (aggravation of liver damage: 18.8% vs. 21.0%, newly developed liver damage: 6.2% vs. 10.5%, both P > 0.05). Conclusion The patients with fungemia in GICU are mainly the infection of Candida parapsilosis, and diabetes, infection of parapsilosis, APACHE Ⅱ score and SOFA score are the risk factors affecting the prognosis of the patients.
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Objective To discuss the clinical application value of serum procalcitonin(PCT) in patients with Candida bloodstream infection.Methods The data of 783 hospitalized patients of Tianjin Medical University General Hospital including blood culture and serum PCT test were retrospectively analyzed,and the medical records of patients with Candida or bacterial bloodstream infection were evaluated by univaxiate and multivariate logistic regression analysis.The comparison of PCT value were carried out among the different blood culture groups using the Mann-Whitney U test.A receiver operating characteristic(ROC) curve was used to determine the diagnostic performance of the PCT.Results The PCT was 0.21 (0.06,1.02) ng/mL in the 510 patients with negative blood culture,but in 121 patients with Candida infection and 152 patients with bacteria infections,the PCT levels were 1.15 (0.38,6.85) ng/ mL and 2.34 (0.77,15.12) ng/mL,respectively.There were statistically significant differences in PCT levels among three groups(P＜0.05).According to ROC,when the value of PCT was 0.355 ng/mL,the sensitivity was 76.9％,and the specificity was 60.8％ with 0.726 area under the curve (AUC) (P＜0.01) for the identification of Candida infection by blood cultures.Conclusions Serum PCT levels have a certain diagnostic value for Candida bloodstream infection.In critically ill patients with factors associated with candidemia,the combination of clinical symptoms with PCT as an adjuvant diagnostic marker and other laboratory findings can be used to make a prompt and effective initiation of antifungal therapy.
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Objective To investigate the antimicrobial resistance profile of the clinical isolates collected from selected hospitals across China. Methods Twenty-nine general hospitals and five children's hospitals were involved in this program. Antimicrobial susceptibility testing was carried out according to a unified protocol using Kirby-Bauer method or automated systems. Results were interpreted according to CLSI 2017 breakpoints. Results A total of 190 610 clinical isolates were collected from January to December 2017, of which gram negative organisms accounted for 70.8％ (134 951/190 610) and gram positive cocci 29.2％ (55 649/190 610). The prevalence of methicillin-resistant strains was 35.3％ in S. aureus (MRSA) and 80.3％ in coagulase negative Staphylococcus (MRCNS) on average. MR strains showed much higher resistance rates to most of the other antimicrobial agents than MS strains. However, 91.6％ of MRSA strains were still susceptible to trimethoprim-sulfamethoxazole, while 86.2％ of MRCNS strains were susceptible to rifampin. No staphylococcal strains were found resistant to vancomycin. E. faecalis strains showed much lower resistance rates to most of the drugs tested (except chloramphenicol) than E. faecium. Vancomycin-resistant Enterococcus (VRE) was identified in both E. faecalis and E. faecium. The identified VRE strains were mainly vanA, vanB or vanM type based on phenotype or genotype. The proportion of PSSP or PRSP strains in the non-meningitis S.pneumoniae strains isolated from children decreased but the proportion of PISP strains increased when compared to the data of 2016. Enterobacteriaceae strains were still highly susceptible to carbapenems. Overall, less than 10％ of these strains (excluding Klebsiella spp.) were resistant to carbapenems. The prevalence of imipenem-resistant K. pneumoniae increased from 3.0％ in 2005 to 20.9％ in 2017, and meropenem-resistant K. pneumoniae increased from 2.9％ in 2005 to 24.0％ in 2017, more than 8-fold increase. About 66.7％ and 69.3％ of Acinetobacter (A. baumannii accounts for 91.5％) strains were resistant to imipenem and meropenem, respectively. Compared with the data of year 2016, P. aeruginosa strains showed decreasing resistance rate to carbapenems. Conclusions Bacterial resistance is still on the rise. It is necessary to strengthen hospital infection control and stewardship of antimicrobial agents. The communication between laboratorians and clinicians should be further improved in addition to surveillance of bacterial resistance.
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To dynamically investigate the distribution and antimicrobial resistance profiles of bacteremia pathogens isolated from different regions in China in 2011, 2013 and 2016. Non-repetitive isolates from nosocomial bloodstream infections were retrospectively collected and detected for antimicrobial susceptibility tests (AST) by agar dilution or microbroth dilution methods. Whonet 5.6 was used to analyze the AST data. Among 2 248 isolates, 1 657 (73.7%) were Gram-negative bacilli and 591 (26.3%) were Gram-positive cocci. The top five bacteremia pathogens were as follows, Escherichia coli (32.6%, 733/2 248), Klebsiella pneumoniae (14.5%, 327/2 248), Staphylococcus aureus (10.0%, 225/2 248), Acinetobacter baumannii (8.7%, 196/2 248) and Pseudomonas aeruginosa (6.2%, 140/2 248). Colistin (96.5%, 1 525/1 581, excluding innate resistant organisms), tigecycline (95.6%, 1 375/1 438, excluding innate resistant organisms), ceftazidine/clavulanate acid (89.2%, 1 112 /1 246), amikacin (86.4%, 1 382/1 599) and meropenem (85.7%, 1 376/1 605) showed relatively high susceptibility against Gram-negative bacilli. While tigecycline, teicoplanin and daptomycin (the susceptibility rates were 100.0%), vancomycin and linezolid (the susceptibility rates were 99.7%) demonstrated high susceptibility against Gram-positive cocci. The prevalence of extended-spectrum β-lactamases (ESBLs)-producing Enterobacteriaceae were 50.6% (206/407), 49.8% (136/273) and 38.9% (167/429) in 2011, 2013 and 2016 respectively; carbapenem-non-susceptible Enterobacteriaceae were 2.2% (9/408), 4.0% (16/402) and 3.9% (17/439) in 2011, 2013 and 2016 respectively; The prevalence of multidrug-resistant A. baumannii (MDRA) was 76.4% (55/72) in 2011, 82.7% (43/52) in 2013 and 87.5% (63/72) in 2016, respectively. The prevalence of multidrug-resistant P. aeruginosa (MDRP) was 9.8% (5/51) in 2011, 20.0% (7/35) in 2013 and 13.0% (7/54) in 2016, respectively. The prevalence of methicillin-resistant S. aureus (MRSA) was 51.9% (41/79) in 2011, 29.7% (19/64) in 2013 and 31.7% (26/82) in 2016, respectively. The prevalence of high level gentamicin resistance (HLGR) of Enterococcus faecium and Enterococcus faecalis were 43.2% (48/111) and 40.9% (27/66), respectively. The predominant organism of carbapenem-non-susceptible Enterobacteriaceae was K. pneumoniae with its proportion of 57.1% (24/42). Among 30 tigecycline-non-susceptible Enterobacteriaceae, K. pneumoniae was the most popular organism with 76.7% (23/30). Among 39 colistin-resistant Enterobacteriaceae, E. coli, Enterobacter cloacae and K. pneumoniae were constituted with the percent of 43.6 (17/39), 35.9 (14/39) and 15.4 (6/39), respectively. The Gram-negative bacilli (E. coli and K. pneumoniae were the major organisms) were the major pathogens of nosocomial bacteremia, to which tigecycline, colistin and carbapenems kept with highly in vitro susceptibility. Whereas, among the Gram-positive cocci, S. aureus was the top 1 isolated organism, followed by E. faecium, to which tigecycline, daptomycin, linezolid, vancomycin and teicoplanin kept with highly in vitro susceptibility. Isolation of colistin-resistant Enterobacteriaceae, tigecycline-non-susceptible Enterobacteriaceae, linezolid- or vancomycin-non-susceptible Gram-positive cocci suggests more attention should be paid to these resistant organisms and dynamic surveillance was essential.
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Objective To investigate antimicrobial resistance among nosocomial gram-negative bacilli in 2016 across China.Methods About 1 394 consecutive and non-repetitive gram-negative bacilli were isolated from 14 teaching hospitals from March to August in 2016 across China.All of these isolates were sent to the central laboratory for reidentification and susceptibility testing.The minimal inhibitory concentration(MICs)of meropenem and other antibacterial agents were determined by agar dilution method.The data were analyzed by using WHONET-5.6 software.Results The activity of antimicrobial agents against Enterobacteriaceae was as follows in descending order of susceptible rate: meropenem (95.2%,891/936), amikacin (94.6%,885/936), ertapenem (92.1%,862/936), piperacillin/tazobactam (88.1%,825/936), imipenem (88.0%,823/936), cefoperazone-sulbactam (83.1%,778/936), cefepime (72.2%,676/936), cefiazidime (72.2%,676/936), levofloxacin(68.8%,644/936), ciprofloxacin (63.2%,592/936), minocyline (62.9%,589/936), cefiriaxone (54.9%,514/936), cefotaxime (54.0%,505/936), cefoxitin (44.3%,415/936).The sensitivities of E.coli to carbapenems, amikacin, piperacillin-tazobactam, polymyxin B and cefoperazone-sulbactam were over 80%.The more sensitive antibiotic to Klebsiella pneumoniae was polymyxin B (99.0%), followed by amikacin (84.9%), meropenem (84.4%) and imipenem (82.0%).The prevalence of extended-spectrum β-lactamase was 62.8%(137/218)in Escherichia coli and 28.3%(58/205)in Klebsiella pneumonia.The activity of antimicrobial agents against E.cloacae, E.aerogenes and Citrobacter freundii was as follows in descending order of susceptible rate: meropenem (97.0%-98.5%), amikacin (95.8%-98.3%), imipenem (94.5%-97.5%), polymyxin B (96.4%-100%), cefoperazone-sulbactam (76.5%-90.0%), ertapenem (73.3%-90.1%), piperacillin/tazobactam (82.4%-88.3%).The most active agents against Pseudomonas aeruginosa were polymyxinB (100%), followed by amikacin (89.3%) and ciprofloxacin (82.4%).The most active agents against Acinetobacter baumannii were polymyxinB (100%).The sensitivities of Acinetobacter baumannii to meropenem, imipenem, minocycline and cefoperazone-sulbactam were 20.3%(39/202), 19.3%(41/202), 66.3%(134/202) and 24.8%(50/202), respectively.Conclusions Carbapenems remain high sensitive against Enterobacteriaceae.Controlling carbapenem resistant Klebsiella pneumoniae is urgent.Drug antimicrobial resistance in A.baumanni is a still serious problem.
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Objective To explore the effect of timing for removing the catheter on prognosis in elderly patients with catheter-related bloodstream infection(CRBSI)and on the death-relevant risk factors.Methods 166 elderly patients with vein detaining catheter and a suspected CRBSI in General Hospital of Tianjin Medical University from 2010 to 2015 were retrospectively analyzed.The patients were divided into a group(n=80)of removing the catheter immediately and a group(n=86)of temporarily not removing the catheter.Mortality rate within 30 days was compared between two groups and mortality-related factors were analyzed.Results In patients with CRBSI,pathogen culture results showed that the detection rate of gram-positive bacteria(G+)was 40.4％ (n=67),the rate of gram-negative bacteria(G)was 40.4％(n=67),and the rate of fungi infection were 19.3％ (n =32).The mortality rate within 30 days was 17.5 ％ in group of removing the catheter immediately,and 31.4％ in group of temporarily not removing catheter.The incidence rate of CRBSI in elder patients was also lower in group of removing the catheter immediately versus not immediately(x2 =4.303,P =0.038).Multiple Logistic regression analysis showed that tumor and diabetes were independent risk factors for death in elder patients with CRBSI (OR =2.805,2.502;P =0.017,0.019).Tumor was a relative risk factor for patients who died after removal of catheter immediately (x2=4.033,P =0.045).Conclusions Removing the vein detaining catheter immediately is an urgent need when the suspected CRBSI symptoms such as chill and hyperpyrexia appear in elderly patients with vein detaining catheter.Nephrotic syndrome,hypoalbuminemia,tumor,diabetes and antibiotic usage＞7 days are risk factors for mortality in CRBSI patients.
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Tuberculosis (TB), an infectious disease caused by Mycobacterium tuberculosis (Mtb) infection,remains a major global concern.The activation of anti-TB immune responses is mediated by several complicated mechanisms, among which the local immune microenvironment at the disease site plays a crucial role.In this review, we discuss the roles of anti-TB immunity, Mtb immune escape and the elements at the local site of infection.
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Objective The epidemiology of Acinetobacter baumannii isolates from bloodstream infections,their antibiotic resistance profiles and virulence-associated factors were studied.Methods A total of 90 isolates from 17 hospitals were collected from the patients with bloodstream infections during July 2013 and July 2014.Vitek-2 Compact system was used for identification of the strains and antibiotic susceptibility testing.The epidemiology was studied by pulsed-field gelectrophoresis(PFGE).Drug-resistant genes and associated virulence genes were amplified by PCR.Results According to antimicrobial susceptibility testing,75 isolates are multi-drug resistant Acinetobacter baumannii.PFGE results showed that 75 multi-drug resistant Acinetobacter baumannii isolates belonged to eight clone types(A to H),with the A (n=51)and B (n=14)clone being the dominant PFGE clone types.Different clone isolates spread in different hospitals.Most of the hospitals were given priority to with clone A.Clone A only maintaining high sensitive rate to cefoperazone/sulbactam、amikacin and tigecycline.Virulence gene abaI,cusE,ompA,bap,bfms detection rates are 93.3% (84/90),92.2% (83/90),100.0% (90/90),84.4% (76/90),92.2% (83/90),respectively.There were 7 mucoid isolates,which are all multi-drug resistant Acinetobacter baumannii,all belong to clone B and all associated virulence genes can be detected.Conclusions The dominant clone type of multi-drug resistant Acinetobacter baumannii from bloodstream infections is clone A.The abaI-,bap-and bfms-positive strains are associated with a higher incidence of antibiotic resistance in most types of antimicrobials.The acquisition of mucous type may indicate the emergence of virulent strains,which should be paid attention to during clinical treatment.
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Objective To establish a real-time quantitative reverse-transcription PCR ( qRT-PCR) method for detection of hepatitis E virus ( HEV) of different genotypes based on standard HEV DNA plasmid in order to promote its application in clinical laboratory. Methods Specific primers and probe of HEV were designed based on the conserved open reading frame 3 (ORF3) regions. HEV DNA plasmids were construc-ted and 10-fold serial dilutions of the plasmids were prepared and used as standards to establish one-step qRT-PCR. The established method was compared with HEV antigen, antibody and RT-nPCR assays. Some positive samples were sequenced and analyzed by evolutionary tree. Results The one-step qRT-PCR meth-od for HEV detection in serum or feces samples was successfully establish. It could reach a sensitivity of 25 copies/test and 77. 8% of its results were consistent with those by HEV antigen assay. Nine patients were infected with HEV of genotypes 4a, 4d or 4n as indicated by evolutionary tree. Conclusion The HEV qRT-PCR method based on its standard plasmid is successfully established, which paves the way for commercial-ization of clinical applications.
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Objective To evaluate the clinical application of the whole blood interferon γ(IFN-γ) release assay of QuantiFERON TB Gold in tube (QFT-GIT) in diagnosis of tuberculosis. Methods From October 2014 to October 2015, 109 patients with tuberculosis (45 cases of confirmed patients and 64 cases of clinically diagnosed patients) and 70 patients with non-tuberculosis were enrolled in Tianjin Medical University General Hospital. In order to evaluate diagnosis value between two kinds of tests, and to compare the differences between two groups, QFT-GIT test and colloidal gold anti tuberculosis antibody (TB-Ab) were employed to detect in two groups of patients. The ROC curve of IFN-γrelease quantity was analyzed in two groups. Results The sensitivity and specificity of QFT-GIT were 93.58% and 85.71% respectively. The positive rate was significantly higher in QFT-GIT than that of TB-Ab (χ2=43.68,P<0.01). The sensitivity of combined detection of the two methods decreased to 52.3% (57/109), but the specificity increased to 90.0% (63/70). The release quantity of IFN-γwas significantly higher in tuberculosis group than that in the non-tuberculosis group (U=330,P<0.05). The area under the ROC curve of IFN-γrelease quantity was 0.913 (95%CI:0.864-0.963). Conclusion The whole blood IFN-γrelease assay of QFT-GIT is a sensitive and specific assay for detecting tuberculosis infection. The combination QFT-GIT with TB-Ab can improve the specificity further, which could be a useful tool for the diagnosis of tuberculosis .
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Rational use of antibiotics can delay the emergence of antimicrobial resistance, and antimicrobial resistance surveillance provides the basis for standardizing clinical rational use of antibiotics. Therefore, antimicrobial resistance surveillance network is of great importance, and its construction can improve the rational use of antibiotics.The construction of antimicrobial resistance surveillance network should emphasize the capacity building of clinical microbiology laboratory and enhance quality control of resistance data based on the standards put forth by Clinical and Laboratory Standards Institute ( CLSI) .
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Objective To investigate the resistance mechanism and virulence genes of clinical strains of carbapenem-resistant Klebsiella pneumonia ( CRKP ) .Methods Twenty clinical CRKP strains were collected from Tianjin Medical University General Hospital during May 2014 and May 2015.Vitek-2 Compact system was used for identification of the strains and antibiotic susceptibility test .Modified Hodge Test and EDTA double disk phenotypic test were performed for screening of drug -resistant phenotypes .Drug-resistant genes , capsular serotypes and associated virulence genes were amplified by PCR , and positive products were sequenced and analyzed by DNA sequencing .Results Resistance to beta-lactam antibiotics including cephalosporins and carbapenems was observed in 80.0%and above strains , but more than 70.0%strains were sensitive to tigecycline , amikacin and levofloxacin .KPC gene and NDM gene were found in 7 strains (35.0%) and 8 strains (40.0%), respectively.SHV, the most common extended-spectrumβ-lactamases ( ESBLs ) gene, was found in 16 strains ( 80.0%). DHA plasmid-mediated AmpCβ-lactamase was found in 2 strains (10.0%).Deletions of porin-coding genes OmpK35 and OmpK36 were found in 8 stains ( 40.0%) and 13 strains ( 65.0%), respectively.Carbapenem-resistant genes in combination with ESBLs genes and/or variation of porin was found in 14 strains (70.0%), and ESBLs genes in combination with variation of porin was found in 4 strains (30.0%).Three strains were of capsular serotype K1 and 1 was of K57, and all of them carried KPC genes .Virulence gene rmpA was found in 8 strains and all carried carbapenemases , among which 5 strains with KPC, 2 strains with NDM, 1 strain with both KPC and NDM .Six strains were aerobactin gene positive , among which 4 strains carried KPC genes . FimH-1 was positive in all strains .Conclusions KPC and NDM genes mainly account for resistance in CPKP, and ESBLs with OmpK gene deletion may also be an important cause .Strains with capsular serotypes K1 and K57 carrying KPC genes are common .