The incidence of intestinal colonization of carbapenem-resistant Enterobacterales and its risk factors for bloodstream infection / 中华检验医学杂志

Objective:The aim of this study was to determine the colonization rate of carbapenem-resistant Enterobacterales (CRE) and identify the proportion and risk factors for bloodstream infection.Methods:This was a retrospective study conducted at the Department of Clinical Laboratory, Peking University People′s Hospital from January 2018 to December 2021. A total of 4 993 patients underwent rectal swab CRE screening for CRE, of which 137 were found to be positive. Clinical and laboratory data of the positive patients were collected, and the following parameters were analyzed: the positive rate of CRE screening in high-risk population, the species of colonized bacteria, antimicrobial resistance and the risk factors of CRE bloodstream infection in colonized patients. Statistical analysis was performed using SPSS 26.0 software. Univariate analysis was conducted using the chi-square (χ 2) test, while multivariate analysis was performed using binary logistic regression. The results were expressed as relative risk (odds ratio, OR) and 95% confidence interval ( CI). A significance level of 0.05 was considered statistically significant. The drug resistance rate of pathogen was analyzed by WHONET 5.6 software. Results:During the study period, a total of 4 991 patients who underwent rectal swab screening were eligible for inclusion, of which 137 patients were screened positive, resulting in a positive rate of 2.7% (137/4 991). The positive rates were higher in the intensive care ward and hematology ward, with rates of 5.5% (27/493) and 3.3% (109/3 321), respectively. A total of 145 colonization strains were isolated from patients with positive CRE screening, including 63 strains of Klebsiella pneumoniae (43.4%, 63/145), 52 strains of Escherichia coli (35.9%, 52/145), 16 strains of Enterobacter cloacae (11.0%, 16/145) and 14 strains of other Enterobacterales (9.7%, 14/145). The metal β-lactamase production type was the main component of CRE positive colonizing bacteria. The antimicrobial resistance of 145 strains to 22 antibacterial agents revealed that amikacin and tigacycline were the most sensitive. Among 137 CRE screening-positive patients, 14 (10.2%, 14/137) developed bloodstream infection. The isolated pathogenic bacteria included 10 Klebsiella pneumoniae strains and 4 Escherichia coli strains, with a predominant serine carbapenemase producing. Notably, the enzyme type and antimicrobial resistance of the bloodstream infection isolates in the same patient were highly consistent with those of the previous screening strains. Comparison was made between patients with positive CRE screening and those with CRE conversion to bloodstream infection. The unifactor analysis revealed significant differences in surgical history, neutropenia, hematopoietic stem cell transplantation, history of antibiotic use before rectal swab screening, screening within 48 hours after admission, and serine carbapenemase production by strains ( P<0.05). The multivariate analysis indicated that surgical history ( OR 24.659, 95% CI 2.540-239.411, P=0.006) and neutropenia ( OR 93.796, 95% CI 6.294-1 397.804, P=0.001) remained significantly associated with the risk of CRE bloodstream infection ( P<0.05). Conclusions:The CRE colonization rate was low in our hospital, but the proportion of patients with positive screening converted to bloodstream infection was high. Surgical history and neutropenia are risk factors for bloodstream infection transmission. Thus, it is essential to enhance monitoring in high-risk areas and susceptible patients.

Clinical evaluation of direct drug sensitivity test for blood culture positive broths / 中华检验医学杂志

Objective:To evaluate the clinical performance of direct antimicrobial susceptibility test in blood culture-positive broth, and to provide a basis for optimizing the antibiotic use strategy in clinical bloodstream infection.Methods:A retrospective analysis was conducted on 780 blood culture-positive samples collected in Peking University People′s Hospital from May 2017 to December 2021. The direct antimicrobial susceptibility test was performed by disk diffusion method on blood culture-positive broth. The antimicrobial susceptibility breakpoints were in accordance with Clinical and Laboratory Standards Institute (CLSI) M100 S32 edition document.Results:In this study, a total of 331 strains of Gram-negative bacteria (139 strains of Escherichia coli, 79 strains of Klebsiella pneumoniae, 35 strains of Pseudomonas aeruginosa, 21 strains of Acinetobacter baumannii) and 396 strains of Gram-positive cocci (25 strains of Staphylococcus aureus, 316 strains of coagulase-negative staphylococci, 47 strains of Enterococcussp.) were collected, after excluding 53 cases with two or more isolates. Compared with the routine antimicrobial susceptibility test (AST), the rates of category agreement (CA), major error (ME), and very major error (VME) of Gram-negative bacteria were 86.0% (1368/1 591), 8.7% (139/1 591), and 0.5% (8/1 591), respectively. On the other hand, the CA%, ME%, and VME% of Gram-positive cocci were 89.2% (960/1 076), 7.5% (81/1 076), and 1% (11/1 076), respectively. Regarding the individual antimicrobial agents, the CA% of Escherichia coli was 16/17 for imipenem, 90.1% (109/121) for meropenem, and 70.8% (85/120) for cefepime. For Klebsiella pneumoniae, the CA% of was 10/13 for imipenem, 80.9% (55/68) for meropenem, and 80.3% (53/66) for cefepime. The CA% of meropenem in Pseudomonas aeruginosa and Acinetobacter baumannii were 96.0% (24/25) and 16/16. The CA% of linezolid and cefoxitin in Staphylococcus aureus were 100% (25/25) and 100% (24/24), respectively. The CA% of linezolid, cefoxitin and gentamicin in coagulase-negative staphylococci were 98.9% (269/272), 94.5% (277/293) and 71.6% (194/271) respectively. Finally, for Enterococcus sp., the CA% of vancomycin and ampicillin were 91.5% (43/47) and 94.7% (36/38), respectively. Conclusion:Compared with the conventional AST, the blood culture-positive broth direct AST exhibited high category agreement and low error rates for both Gram-negative bacteria and Gram-positive cocci, which can serve a rapid alternative for AST in cases of clinical bloodstream infection.

Effect evaluation of optimizing blood culture testing process / 中华检验医学杂志

Objective:To evaluate whether the time to positive (TTP), handling time after positive alarm and turnaround time (TAT) of bacteremia blood culture can be shortened by optimizing blood culture workflow.Methods:This study was conducted retrospectively. Positive blood culture samples collected from Peking University People′s Hospital from January 1, 2014 to June 30, 2021 were analyzed in stages. In the traditional process stage of this study (2014), 502 bottles of positive blood culture samples were included in the analysis. In the first stage of process optimization (2016), the working time of staff was increased to 22:00, and 976 positive blood culture specimens were included in the analysis. In the second stage of process optimization (2018), the rapid identification process of MALDI-TOF MS was added, and a total of 1 029 bottles of positive blood culture samples were included. In the third stage of process optimization (2020) with the introduction of the new VIRTUO BACT/ALERT system. The difference of TTP, handling time after positive alarm and TAT of whole process in different stages of traditional process and process optimization were compared. All data were statistically significant when P<0.05 using rank-sum test. Results:In the traditional process stage (2014), the median quartile time of handling time after positive alarm was 55.70 (47.35, 68.45) h. In the first stage of process optimization (2016), the median quartile time of handling time after positive alarm was 47.25 (33.88, 59.96) h, and the handling time after positive alarm in the first stage of process optimization was significantly shorter than that in the traditional process stage ( Z=?10.734, P<0.001). In the second stage of process optimization (2018), the median quartile time for handling time after positive alarm was 47.18(36.41, 59.40) h, and 12.18% of the preliminary identification results of Gram-negative bacilli before 17:00 could be reported to the clinic before audit. In the third stage of process optimization (2020), the median quartile of TTP and TAT were 39.56 (21.52, 62.65) h and 78.16(64.68, 99.72) h respectively in the original BACT/ALERT 3D system. The new VIRTUO BACT/ALERT system had a median quartile of 37.03(21.08, 58.22) h for TTP and 73.41(62.88, 89.48) h for TAT. VIRTUO BACT/ALERT 3D had a significantly shorter TTP than BACT/ALERT 3D ( Z=?2.273, P=0.023), the TAT of VIRTUO BACT/ALERT system was significantly shorter than that of BACT/ALERT 3D system ( Z=?4.040, P<0.001). Conclusion:By improving the blood culture process of microbiology laboratory in many aspects and measures, the processing time of blood culture in each stage can be shortened and clinical benefits can be obtained.

Curative effect and aesthetics analysis of 40 patients with breast fibroadenoma treated by ring -areola incision / 中国基层医药

Objective To analyze the immune function and shoulder function of sentinel lymph node biopsy combined with mastectomy in patients with early breast cancer.Methods A total of 80 patients with breast fibroadenoma were selected ,and they were randomly divided into surround -mammary areola incision group ( n=40 ) and conven-tional radial incision group(n=40) according to the digital table.The bleeding volume,operation time,hospital stay, satisfaction and curative effect were compared between the two groups .Results The markedly effective rate of surround-mammary areola incision group was 87.50％,which was significantly higher than that of the radial incision group(62.50％),and the difference was statistically significant (χ2 =10.400,P=0.001).The total effective rate was 100.00％in the surround -mammary areola incision group ,which was significantly higher than that in the radical incision group(χ2 =6.500,P=0.010).The time of operation,the amount of bleeding and the length of hospital stay in the surround-mammary areola incision group were (56.7 ±3.2) min,(62.1 ±1.8) mL and(8.3 ±0.8) d, respectively,which were lower than those in the radial incision group [(69.8 ±4.3)min,(71.1 ±2.4)min,(11.2 ± 1.3)d],there were statistically significant differences between the two groups (t=15.262,P=0.000;t=18.735, P=0.000;t=11.864,P=0.000).The incidence rates of breast milk symmetry,scar acceptance and adverse reaction in surround-mammary areola incision group were 87.50％,87.50％ and 2.50％,respectively,which were significantly better than those in the radial incision group(67.50％,65.00％ and 15.00％),there were statistically significant differences between the two groups (χ2 =5.032,P=0.024;χ2 =7.862,P=0.005;χ2 =3.923,P=0.047).The total satisfaction rate was 87.50％in the surround-mammary areola incision group ,which was higher than 62.50％in the radial incision group (χ2 =7.222,P=0.007).Conclusion The use of surround -mammary areola incision in the treatment of patients with breast fibroadenoma has obvious effect ,can reduce the degree of breast injury ,improve the physical appearance of the breast ,with high satisfaction .

Microbiological profiles of pathogens causing nosocomial bacteremia in 2011, 2013 and 2016 / 生物工程学报

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.

Rapid identification of pathogenic organisms positive for blood culture by MALDI-TOF mass spec-trometry in combination with Sepsityper Kit or serum-separating gel tubes / 中华微生物学和免疫学杂志

Objective To evaluate the feasibility of using matrix-assisted laser desorption/ioniza-tion time-of-flight mass spectrometry(MALDI-TOF MS) in combination with Sepsityper Kit or serum-separa-ting gel tubes for identification of pathogenic organisms positive for blood culture. Methods A total of 153 clinical specimens with a positive result in blood culture were collected and tested with MALDI-TOF MS in combination with Sepsityper Kit or serum-separating gel tubes. Test results were compared with those by using culturing. Results The 153 positive blood culture specimens included 143 of single bacterial infection and 10 of multiple bacterial infections. The consistency rates at species and genus levels were 76.2% (109/153) and 7.8% (12/153) between Vitek 2 Compact method and MALDI-TOF MS combined with Sepsityper Kit,and 75.1% (101/153) and 8.5% (13/153) between Vitek 2 Compact method and MALDI-TOF MS combined with serum-separating gel tubes. In the identification of single bacterial infection specimens, the consistency rates of MALDI-TOF MS combined with Sepsityper Kit at species and genus levels were 95.2% (79/83) and 0% (0/83) for gram-negative bacteria,57.5% (27/47) and 23.4% (11/47) for gram-pos-itive bacteria and 33.3% (3/9) and 11.1% (1/9) for Candida,the consistency rates of MALDI-TOF MS combined with serum-separating gel tubes at species and genus levels were 90.4% (75/83) and 4.8% (4/83) for gram-negative bacteria,55.3% (26/47) and 14.9% (7/47) for gram-positive bacteria and 0% (0/9) and 22.2% (2/9) for Candida. MALDI-TOF MS combined with Sepsityper Kit was only consistent with Vitek 2 Compact method in the identification of one specimen of multiple bacterial infections. Conclu-sion MALDI-TOF MS in combination with Sepsityper Kit or serum-separating gel tubes can identify the pathogens positive for blood culture within one hour and is of high consistency with culturing. In comparison with the traditional identification method for positive blood cultures, MALDI-TOF MS combined with Sepsi-typer Kit or serum-separating gel tubes has the advantages of rapidity and easy operation, which meet the clinical needs of rapid diagnosis and timely and effective antibacterial treatment,and is of great value in clin-ical application.

Effect evaluation of adenosine triphosphate bioluminescence test on quality monitoring of flexible endoscope reprocessing / 中华消化内镜杂志

Objective To evaluate the efficacy of adenosine triphosphate ( ATP ) bioluminescence test on quality monitoring of flexible endoscope reprocessing. Methods The patient-used gastroscopes were randomly assigned to two groups after standard reprocessing by one nurse. The group A were assessed by ATP test followed by microbiological surveillance test after cleaning and disinfection; and the gastroscopes in group B were tested in a reverse order. The biological load after endoscopic cleaning and disinfection were compared between ATP test and microbiological surveillance, and the correlation of the two tests on quality assessing of endoscopic cleanliness and disinfection were analyzed. Results A total of 51 samples were valid. The qualified rate of cleaning was 45. 1％ ( 23/51) detected by ATP test, and the qualified rate of disinfection was 92. 2％ ( 47/51) detected by microbiological surveillance. There was no statistical difference in cleaning qualification rate ( 50. 0％ VS 40. 0％,χ2=0. 515, P=0. 473) and disinfection qualification rate ( 96. 2％ VS 88. 0％,χ2=0. 316, P=0. 574) between the two groups. The logarithmic value of relative light unit ( RLU) of ATP test after cleaning was higher than the value after disinfection ( 1. 68 ± 0. 50 VS 0. 88 ±0. 49, t=2. 335,P=0. 024) . For gastroscopes disinfected appropriately, the RLU logarithmic value of ATP test after cleaning ( t=2. 505, P=0. 016) and disinfection ( t=2. 485, P=0. 016) were lower than that of disqualification. The correlation between the value of ATP test and the colony forming units of microbiological surveillance after cleaning was not statistically significant ( r=0. 199, P=0. 171 ) , but there was a low correlation between the two monitoring results after disinfection (r=0. 391, P=0. 005). There was a low correlation between the value of ATP test after cleaning and the colony forming units of microbiological surveillance after disinfection ( r=0. 301, P=0. 032) . Conclusion ATP bioluminescence test can be used to evaluate the trend of endoscopic biological load change and the quality of flexible endoscope reprocessing.

A retrospective evaluation of the performance of 2 blood culture media in detection of bloodstream infection: clinical comparison of BACTEC and BacT/Alert systems / 中华检验医学杂志

Objective To evaluate the clinical performance of the BACTEC Plus aerobic,BACTEC Lytic anaerobic,BacT/Alert aerobic and anaerobic blood culture media in detection of bloodstream infections.Methods Retrospective study was conducted.A total of four blood culture bottles from each inpatient with suspected bloodstream infections were collected and analyzed from June 2013 to September 2015 in Peking University People's Hospital.The four bottles,including BACTEC Plus aerobic,BACTEC Lytic anaerobic,BacT/Alert FA aerobic and BacT/Alert FN anaerobic media,and was incubated for 5 days in the BacT/Alert 3D and BACTEC FX instruments,respectively.Time to detection (TTD) and positive rate in detecting bacteria of the two systems were evaluated by Wilcoxon test and Chi-square test.Results Among 2 189 total cultures collected,20 were excluded because of blood shortage and 201 (9.27％) were positive for pathogens.The positive rates of BACTEC Plus aerobic media and BacT/Alert FA aerobic media were 75.3％ (140/186) and 69.4％ (129/186) (x2 =1.625,P=0.202),respectively.While,the positive rates of BacT/Alert FN anaerobic media and BACTEC Lytic anaerobic media were 81.8％ (99/121) and 63.6％ (77/121) for total organisms,respectively (x2 =10.083,P =0.001).A significant difference in TTD was detected in BACTEC Plus aerobic media[11.0 (8.0-16.0) h] and BacT/Alert FA aerobic media[13.9 (10.4-18.7) h] (Z =-5.240,P ＜ 0.001).BACTEC Lyric anaerobic media[8.0(7.0-10.0) h] had a shorter TTD (Z =-4.299,P ＜ 0.001) than BacT/Alert FN anaerobic media[11.3(9.3-12.7) h].The positive rates of BACTEC and BacT/Alert system were 74.13％ (149/201) and 74.63％ (150/201),respectively,compared with taking one set from each system.Conclusions BACTEC media has a shorter TTD and almost the same bacterial recovery,and lower false positive rate than the BacT/ Alert media.

Safety of Intra-articular Injection of Bevacizumab in the Knee Joint of Rabbit / 医药导报

Objective To evaluate the toxicity of the intra-articular injection of bevacizumab in the knee of the rabbit.Methods Thirty-two rabbits were divided into 3 experimental groups and normal control group.Three experimental groups were received intra-articular injection of bevacizumab (1, 2, 4 mg respectively) once every three weeks for two times and the normal control group was received the same amount of 0.9% sodium chloride solution.The animals were sacrificed after 6 weeks.Blood test was examined before and after treatment.Pathologic examinations of liver, kidney and artiluar tissue were taken after the sacrifice.The hematoxylin and eosin stain for synovium and cartilage were performed.The AB-PAS stain and Mankin's scale for cartilage were performed.Results All the rabbits kept normal physiological activity.There was no significant difference of major organs and articular tissue between experimental groups and normal control group.There was no significant difference for WBC, RBC, PLT, ALT, BUN and Mankin's scale among all groups.Conclusion No systemic toxicity effects were found for the intra-articular injection of bevacizumab in the knee of the rabbit.

Molecular mechanisms of colistin-resistant Klebsiella pneumoniae and Escherichia coli isolates / 中华检验医学杂志

Objective To elucidate the resistance mechanisms of clinical colistin-resistant Klebsiella pneumoniae and Escherichia coli isolates in China.Methods A total of 964 K.pneumoniae and 1 389 E. coli isolates were retrospectively collected from national surveillance programs from 2011 to 2014 in China. Antimicrobial susceptibility testing was determined by the microdilution method.The PCR amplification followed by sequencing was used to detect the mcr-1 gene and colistin-resistance genes, including mgrB, pmrB and phoQ.Real-time quantitative PCR was performed to examine the relative transcriptional levels of pmrB, pmrC, pmrD, pmrK and pmrE genes in K.pneumoniae, and pmrA, pmrB, pmrC, phoP and phoQ genes in E.coli.Conjugation experiment was used to detect the transferability of the resistance plasmid carrying the mcr-1 gene.Statistical analyses were performed using IBM SPSS Statistics (version 16.0) and a P value <0.05 was considered statistically significant. Results The colistin-resistant rates of K. pneumoniae and E.coli were 0.62% ( 6/964 ) and 1.66% ( 23/1 389 ) , respectively.No amino acids substitutions were identified in mgrB genes among colistin-resistant isolates.Among six colistin-resistant K. pneumoniae isolates, five isolates were identified to have point mutations in pmrB gene, but no point substitution was detected in phoQ gene.One to four point mutations had been found in pmrB and phoQ genes in colistin-resistant E.coli isolates, respectively.The expression level of pmrB, pmrC, pmrD, pmrK and pmrE genes showed no significant difference between colistin-resistant and colistin-susceptible isolates [pmrB, (1.04 ±1.12) vs.(0.94 ±0.67), P=0.945; pmrC, (1.39 ±2.01) vs.(0.16 ±0.27), P=0.101;pmrD, (1.59 ±2.43) vs.(0.88 ±0.34),P=0.445;pmrK, (0.64 ±0.62) vs.(0.04 ±0.10), P=0.051;pmrE, (3 492 833 388.83 ±8 478 977 986.85) vs.(20 771 428.93 ±38 000 732.85), P=0.445].However, the transcriptional level of pmrB genes in colistin-resistant group was 9.5-fold higher than that of the colistin-susceptible group in E.coli isolates.Four in six colistin-resistant K.pneumoniae isolates possessed mcr-1 gene, whereas all of the colistin-resistant E. coli had the mcr-1 gene. The conjugation verified the transferability rate of the plasmid carrying mcr-1 gene was 5.78 ×10-6 , and the MIC value of colistin of the conjugant increased 21-fold than the recipient strain.Conclusions Plasmid-mediated mcr-1 gene was the major reason for colistin resistance in clinical isolates of K.pneumoniae and E.coli. Some other resistance mechanisms such as transcriptional up-regulated pmrB gene also involved in colistin resistance.

Intraarticular injection of bevacizumab in treatment of osteoarthritis:a laboratory research on a rabbit model / 北京大学学报(医学版)

Objective:To evaluate the effects of intraarticular injection of bevacizumab、sodium hyalu-ronate (SH)and 0.9% sodium chloride injection in the treatment of osteoarthritis (OA)in a rabbit model.Methods:Twenty-four male rabbits were randomly divided into bevacizumab group,SH group and control group after the model of OA had been made.The bevacizumab group and control group received intraarticular bevacizumab (4 mg)and 0.9% saline injection respectively once per three weeks for 2 times.The SH group received intraarticular SH once a week for 6 weeks.After 6 weeks,the histological examinations of cartilage and synovium,electron microscopy and expression of vasculan endothelial growth factorl (VEGF),for the synovium,expression of MMP-1 ,Mankin’s scale,macroscopic observation for cartilage were performed.Results:The histological observation of the bevacizumab group and the SH group showed that bevacizumab could decrease the synoviocytes and inhibit fibrous hyperplasia in synovial underlayer compard with the control group.Reduced apoptosis of chondrocytes and more integrated struc-ture of matrix and more glycosaminoglycan were also found in the bevacizumab group and the SH group compared with control group.The expression of VEGF and MMP-1 ,Mankin’s scale,macroscopic obser-vation were significantly decreased in the bevacizumab group compared with the SH group and the control group (P<0.05).Conclusion:Intraarticular injection of bevacizumab and SH can relieve inflammation of OA and alleviate the pathologic process of OA.The Bevacizumab was better than the SH in therapeutic effect,which maybe implicate a better choice for the treatment of OA.

Antimicrobial resistance surveillance of gram-positive cocci isolated from 15 teaching hospitals in China in 2013 / 中华检验医学杂志

Objective Toinvestigateantimicrobialresistanceamonggram-positivecocciinChinain 2013.Methods Retrospectivestudy.FromJune2013toDecember2013,1663consecutiveandnon-repetitive gram-positive cocci were collected from 15 teaching hospitals. The minimal inhibitory concentration ( MIC) of antibacterial agents was determined by agar dilution method. A retrospective study was conducted on rates of resistance to antimicrobial agents. The prevalence of penicillin-resistant Streptococcus pneumoniae ( PRSP) between children and adult patients and the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) between elder group and younger adult patients were compared using chi-square test. Results The prevalence of PRSP in children below 3 years old ( 72. 9%, 51/70 ) was higher than adult patients (55. 2%, 106/192) (χ2 =6. 653,P<0. 05). About 94. 9%(261/275) and (92. 7%,255/275) of S. pneumonia were resistant to erythromycin and clindamycin. All S. pneumoniae strains were susceptible to teicoplanin, vancomycin, linezolid, tigecycline and daptomycin. Penicillin still showed very high activity against Streptococcus spp. β-Hemolytic group. More than 60% of Streptococcus spp.β-Hemolytic group were resistant to erythromycin, clindamycin and tetracyclines. The prevalence of MRSA and methicillin-resistant coagulase-negative Staphylococci(MRCoNS) was 39. 7%(229/576) and 80. 6%(224/278), respectively. The MRSA prevalence ranged from 24. 2% to 70. 0% in different regions. About 52. 6%( 100/190 ) of Staphylococcus aureus from respiratory tract specimens, 38. 5%(40/104)of Staphylococcus aureus from blood samples, and 29. 7%(58/195) of Staphylococcus aureus from wound and pus were resistant to methicillin. The prevalence of MRSA in elder group ( 48. 6%, 84/173 ) was higher than that in younger adult patients (35. 7%, 144/403)(χ2 =8. 322,P <0. 05). The susceptibility rates of MRSA to chloramphenicol and trimethoprim/sulfamethoxazole were 86. 4% ( 244/228 ) and 94. 7% ( 237/228 ) , respectively. Susceptibility rates to gentamycin, erythromycin, clindamycin, tetracyclines, rifampicin and quinolones were ranged from 15. 8% to 59. 6%. All Staphylococci isolates were susceptible to teicoplanin, vancomycin, linezolid, daptomycin and tigecycline. All Enterococcus isolates were susceptible to daptomycin and tigecycline. All E. faecalis ( 158/158 ) and 96. 4% ( 133/138 ) of E. faecium were susceptible to teicoplanin. About 98. 0% ( 150/153 ) of E. faecalis and 97. 1% ( 145/138 ) of E. faecium were susceptible to linezoild. About 45. 8% (70/153) of E. faecalis and 60. 9% (84/138) of E. faecium were resistant to gentamycin with a high concentration. The susceptibility of E. faecalis to all the antibiotics tested exceptchloramphenicolandtetracyclinewashigherthanthatofE.faecium.Conclusions Basedon different age groups and regions, the resistance rates of Gram-positive cocci are different. Teicoplanin, vancomycin, tigecycline, daptomycin, linezolid and tedizolid showed very high activity against Gram-positive cocci. (Chin J Lab Med,2015,38:373-381)

The influencing factors and methodological evaluation on tigecycline susceptibility testing methods for Acinetobacter baumannii and Klebsiella pneumoniae / 中华检验医学杂志

Objective To investigate the factors affecting the susceptibility of tigecycline and assess the testing methods.Methods The 116 isolates of Acinetobacter baumanaii and Klebsiella pneumoniae were collected in 13 hospitals from January to December,2010,to evaluate the effects on the tigecycline susceptibility of the overnight medium,medium brand and lot number,respectively.The 56 isolates of Acinetobacter baumannii and the 47 isolates of Klebsiella pneumoniae were selected randomly according to the MIC distribution proportion in 2010 and 2012.The broth microdilution was taken as the reference method to evaluate the effects of the agar dilution,disk diffusion,MIC Test Strip (MTS) and Vitek2 (GN16) on the susceptibility of tigecycline.Results The essential agreement (EA) of Acinetobacter baumannii and Klebsiella pneumoniae is 89.7％ (52/58)and 87.9％ (51/58) using overnight medium and fresh medium respectively.Both EA and categorical agreement (CA) of the different brands (BBL and Oxoid) and lot numbers are 100％ using agar dilution.According to the FDA break point criteria,the CA/EA is 77.7％ (80/103)/99.0％ (102/103),87.4％ (90/103)/98.1％ (101/103),64.1％ (66/103)/76.7％ (79/103) using agar dilution,MTS,Vitek (GN16) with respect to broth microdilution.The CA is 79.6％ (82/ 103,S≥14 mm,R≤10 mm),69.9％ (72/103,S≥ 16 mm,R≤ 12 mm),34.0％ (35/103,S≥19 mm,R≤14 mm)using disk diffusion method compared with broth microdilution (FDA break point criteria).Conclusions The susceptibility of tigecycline must be tested using fresh medium.The medium brands and lot numbers used in this test have no effects on the tigecycline susceptibility to Acinetobacter baumannii and Klebsiella pneumoniae.There exist the better correlations on MIC using agar dilution and MTS than the disk diffusion and Vitek(GN16) compared with broth microdilution.It is expected that the consistency can be improved by adjusting the break point of disk diffusion.

In vitro susceptibility of commonly used antibiotics on community-acquired uncomplicated urinary tract infection pathogens in Beijing / 中华泌尿外科杂志

Objective To investigate the distribution and susceptibility patterns of common uropathogens causing community-acquired urinary tract infection (UTI) in Beijing.MethodsA total of 300non-duplicate isolates were randomly collected from 3 hospitals in Beijing between Jan,1 2010 and Mar,312011.Minimal inhibitory concentrations (MICs) were determined by the broth microdilution methods,which were performed and interpreted according to the guidelines established by the Clinical and Laboratory Standards Institute (CLSI).A panel of 8 antimicrobial agents were tested:amikacin,cefaclor,cefepime,cefoperazone/sulbactam,ciprofloxacin,levofloxacin,gentamicin and nitrofurantoin. Fosfomycin trometamol MICs were determined by the agar-dilution method in cation-adjusted MH agar supplemented with glucose 6-phosphate at a concentration of 25 mg/L as detailed in the guidelines issued by 2010 CLSI. All the Escherichia coli,Klebsiella pneumoniae and Proteus mirabilis strains were screened and confirmed by double-disk synergy test for extended-spectrum β-lactamase (ESBLs).Results Among the organisms cultured,E.coli wasthepredominantpathogen(65.0％ ), followedby Enterococcus(11.7％ ),Staphylococcus( 6.3％ ), Klebsiella pneumoniae( 5. 3％ ), Proteus mirabilis( 4. 7％ ), and Pseudomonas aeruginosa (3.0％).Lower susceptibility rates to ciprofloxacin and levofloxacin (31.4％ -47.4％ ) were observed among all the stains.Amikacin,cefoperazone/sulbactam,nitrofurantoin and fosfomycin trometamol were the most active drugs (92.1％,92.1％,88.4％ and 87.9％ susceptible strains,respectively) among the Gram-negative strains.Isolates of Staphylococcus were highly sensitive to amikacin ( 100.0％ ),cefoperazone/sulbactam (94.7％),nitrofurantoin ( 100.0％ ).Higher susceptibility rates to nitrofurantoin (91.4％) and fosfomycin trometamol (90.0％) were observed in Enterococcus.ESBLs-producing strains accounted for 52.3％ (102/195) in E.coli,43.8％ (7/16) in K.pneumoniae and 14.3％(2/14) in P.mirabilis,respectively.ConclusionsResistance is most common to ciprofloxacin and levofloxacin of all the stains.Currently,the most appropriate agents for the empirical management of uncomplicated UTI seems to be amikacin,cefoperazone/sulbactam,nitrofurantoin and fosfomycin trometamol.

Antimicrobial resistance surveillance of gram-positive cocci isolated from 14 hospitals in China in 2011 / 中华检验医学杂志

Objective To investigate antimicrobial resistance among gram-positive cocci in 14 teaching hospitals in China in 2011.Methods From June 2011 to December 2011,1498 consecutive and non-repetitive gram-positive cocci were collected from 14 teaching hospitals.The minimal inhibitory concentration (MIC) of antibacterial agents was determined by agar dilution method.A retrospective study was conducted on rates of resistance to antimicrobial agents.Data was compared using chi-square test.Results The prevalence of methicillin-resistant Staphylococcus aureus (MRSA) and methicillinresistant coagulase-negative Staphylococci (MRCoNS) was 43.7％ (222/508),and 85.6％ (214/250),respectively.The MRSA prevalence ranged from 20.0％ to 63.5％ in different regions.About 58.2％ (82/141) of Staphylococcus aureus from respiratory tract specimens,44.8％ (48/107) of Staphylococcus aureus from blood samples,and 23.8％ (31/130) of Staphylococcus aureus from pus and wound were resistant to methicillin.The susceptible rates of MRSA to chloramphenicol and sulfamethoxazole-trimethoprim SXT were 94.1％ (209/222) and 83.3％ (185/222),respectively.Susceptibility to gentamycin,erythromycin,clindamycin,tetracyclines,rifampicin and quinolones were from 11.3％ to 52.3％.All Staphylococci isolates were susceptible to vancomycin,teicoplanin,linezolid and daptomycin.Five vancomycin-resistant enterococcus (VRE) strains were found in this study.All enterococcus isolates were susceptible to daptomycin(268/268),and 98.3％ (118/120) of E.faecalis and 99.3％ (147/148) of E.faecium were susceptible to linezoild.About 45.9％ (68/148) of E.faecalis and 67.5％ (81/120) of E.faecium were resistant to high concentration gentamycin.The susceptibility of E.faecalis to all the antibiotics except for chloramphenicol and tetracycline was higher than that of E.faecium.The prevalence of penicillinnonsusceptible Streptococcus pneumoniae (PNSSP) was 15.5％ (37/239).The prevalence of PNSSP in children below 3 years-old was 25％ (13/52),and the prevalence of PNSSP from other patients was 13％(24/187).About 91.6％ (219/239),88.7％ (212/239) and 88.3％ (211/239) of S.pneumonia was resistant to erythromycin,clindamycin and tetracyclines.All S.pneumoniae strains were susceptible to teicoplanin,vancomycin,linezolid,tigecycline and daptomycin.Penicillin still showed high activity against Streptococcus spp.β-hemolytic group.More than 60％ of Streptococcus.spp.β-hemolytic group are resistant to erythromycin,clindamycin and tetracyclines.Conclusions Based on regions,the resistance rates of Gram-positive cocci are different,of which,the increasing tendency should be taken seriously.Teicoplanin,vancomycin,linezolid,tigecycline and daptomycin show very high activity against Gram-positive cocci.

The antibiotic susceptibility and extended spectrum β-lactamase genotype of clinical Klebsiella pneumoniae / 中华检验医学杂志

Objective To analyze the antibiotic susceptibility, ESBL genotype of clinical Klebsiella pneumoniae strains isolated from People′s hospital and facilitate the control of resistance spread. Methods Identification and antibiotic susceptibility tests of 1 205 strains from 2001 to 2007 were done by VITEK-2 system.The antibiotic susceptibility results were analyzed by whonet5.3.The ESBL gene was detected by PCR and the Chi-square test was used for statistical analysis.Results The rate of ESBL-producing strains in klebsiella pneumoniae has increased from 2001 to 2007[18.8% (40/213) in 2001, 20.9% (53/253) in 2002, 32.8% (42/128) in 2003, 33.6% (45/137) in 2004, 36.6% (60/164) in 2005, 45.3% (68/150) in 2006 and 45.6% (73/160) in 2007].The SHV gene was the most dominant in ESBL genotypes.There were 83.3% (50/60) ESBL strains in 2005 with SHV gene, 82.3%(56/68) in 2006 and 83.6%(61/73) in 2007.The rated of strains with CTX-M gene were increasing.There were 26.7%(16/60) ESBL strains with CTX-M gene in 2005, 36.7%(25/68) in 2006 and 54.8%(40/73) in 2007.The isolates with more than one type of ESBL gene were increasing.There were 45%(27/60) ESBL strains in 2005 with two types of ESBL gene, and no one had more than two types of ESBL gene in that year.There were 47.9%(35/73) ESBL strains in 2007 with two types of ESBL gene.In 2007 there were 9.6%(7/73) and 2.7%(2/73) ESBL strains with three types and four types of ESBL gene respectively.There was a statistical difference between the antibiotic resistance rates of cefotaxime, ceftriaxone and ceftazidime in SHV-gene-phore strains (χ2=13.22, P＜0.01).The strains with SHV gene were more resistant to cefotaxime than ceftriaxone and ceftazidime.There also was a statistical difference of the antibiotic resistance rate of cefotaxime, ceftriaxone and ceftazidime between strains with TEM gene (χ2=9.91, P＜0.01) and CTX-M gene (χ2=34.84, P＜0.01) respectively.None of the strains with CTX-M gene was sensitive to cefotaxime, and they were more resistant to ceftriaxone than ceftazidime.The strains with TEM gene were more resistant to cefotaxime than ceftriaxone and ceftazidime.There were statistical differences of the antibiotic resistance rate to cefotaxime (χ2=29.65, P＜0.01), ceftriaxone (χ2=20.26, P＜0.01) and ceftazidime (χ2=20.26, P＜0.01) between the strains with SHV gene only and strains with SHV and CTX-M gene concurrently.There were also statistical differences of the antibiotic resistance rates to cefotaxime (χ2=11.01, P＜0.01), ceftriaxone (χ2=9.93, P＜0.01) and ceftazidime (χ2=7.01, P＜0.01) between the strains with SHV gene only and strains with SHV and TEM gene concurrently.The antibiotic resistance rates to cefotaxime (χ2=11.54, P＜0.01), ceftriaxone (χ2=17.58, P＜0.01) and ceftazidime (χ2=14.11, P＜0.01) were statistically different between the strains with SHV gene only and strains with SHV and OXA gene concurrently.The antibiotic resistance rates to ceftazidime (χ2=23.61, P＜0.01) were statistically different between the strains with CTX-M gene only and strains with SHV and CTX-M gene concurrently. There was no statistical difference in antibiotic resistance rates to cefotaxime (χ2=3.55, P＜0.01) and ceftriaxone (χ2=3.35, P＜0.01) between the strains with CTX-M gene only and strains with SHV and CTX-M gene concurrently. The antibiotic resistance rates to ceftazidime (P=0.01) were statistically different between the strains with only TEM gene and strains with SHV and TEM gene concurrently, and there was no statistical difference of the antibiotic resistance rates to cefotaxime (P=0.29) and ceftriaxone (P=0.26) between the strains with TEM gene only and strains with SHV and TEM gene concurrently. ConclusionsThe producing rate of ESBL is increasing year after year and the SHV type of ESBL is the dominant one.Strains with more than one type of ESBL gene are increasing.The antibiotic resistance rates to cefotaxime, ceftriaxone and ceftazidime are statistically different between strains with same ESBL genotype.

Report from Chinese Meropenem Susceptibility Surveillance in 2010 : antimicrobial resistance among nosocomial gram-negative bacilli / 中华检验医学杂志

Objective To investigate antimicrobial resistance among gram-negative bacilli in China in 2010.Methods A total of 1 259 consecutive and non-repetitive gram-negative bacilli were isolated from 13 teaching hospitals from September to December in 2010 in China.All of these isolates were sent to the central laboratory for re-identification and susceptibility testing.The MIC of meropenem and other antibacterial agents were determined by agar dilution method.Interpretive results was determined by CLSI M100-S21.Results The activity of 14 antibacterial agents against 845 Enterobacteriaceae isolates was as follows in order:meropenem ( 98.1％,829 ),amikacin ( 94.0％,794 ),imipeuem ( 90.0％,761 ),piperacillin/tazobactam ( 87.5％,739 ),cefepime ( 83.0％,701 ),ertapenem ( 82.4％,696 ),cefoperazone/sulbactam ( 80.3％,678 ),colistin (75.4％,637),ceftazidime (70.0％,591 ),ciprofloxacin (59.1％,499 ),cefoxitin ( 54.8％,463 ),ceftriaxone ( 53.5％,452 ),cefotaxime ( 52.3％,442 ) and minocycline(51.5％,435).The prevalence of ESBL was 61.3％ (106/173) in Escherichia coli,which was much higher than 41.2％ (70/170) in Klebsiella pneumoniae.The susceptibility rate of Klebsiella pneumoniae against meropenem,imipenem,amikacin and colistin were more than 90％,but were highly resistant to ceftriaxone and cefotaxime.Over 80％ of Enterobacter cloacae,Enterobacter aerogenes,Citrobacter freundii,were susceptible to meropenem,amikacin,cefepine,cefoperazone/sulbactam,imipenem,piperacillin/ tazobactam,and ertapenem.The most active antibiotics against Pseudomonas aeruginosa were Colistin (98.4％,182),Amikacin ( 85.9％,159 ),Piperacillin/Tazobactam ( 80％,148 ),Ceftazidime ( 79.5％,147),Meropenem (74.1％,137),Ciprofloxacin (74.1％,137),Cefepime (73.5％,136),Imipenem (71.9％,132) and Cefoperazone/Sulbactam (70.8％,131 ).Less than 37％ of Acinetobacter baumannii isolates were resistant to carbapenems.The susceptible rate to Minocycline was 47.8％.Colistin kept good activity against Acinetobacter baumannii (susceptible rate,97.8％,n =176),The prevalence of Pan-drug resistant P.aeruginosa and A.baumannii was 18.9％ (n =35),and 61.8％ (n =108),respectively.Conclusions Carbapenems remained very high activity against Enterobacteriaceae.Increasing resistance to the antimicrobials agents test among A.baumanni and P.aeruginosa,especially carbapenems among A.baumanni brought great concern.

Surveillance to Invasive Fungal Infection in Surgical Intensive care Unit During 6-years / 中华医院感染学杂志

OBJECTIVE To surveillance invasive fungal infection rate in SICU,in order to direct intervention to prevent invasive fungal infection.METHODS The samples collected from SICU patients in our hospital between Jan 2003-Nov 2008 were cultured.RESULTS According to the diagnosis standard of nosocomial infections,75 case of 3699 patients were isolated fungi.During 6-years invasive fungal infection rate is 2.027%,(1.05%-2.63%).Totally 86 fungi strains were isolated,the majority of them being Candida albicans,accounting for 46.51%;Candida glabrata 22.09%;Candida tropicalis 13.95%.CONCLUSIONS During 6-years,invasive fungal infection rate and incidence density do not increase.Candida are the major pathogens of fungal infections in SICU.