1.Distribution and Resistance to Antibiotics of Shigella in Anhui Province
Lifen HU ; Jun CHENG ; Jiabin LI ; Zhongxin WANG ; Xu LI
Chinese Journal of Nosocomiology 2006;0(02):-
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.
2.Evaluate the effect of mucosal healing after low-dose azathioprine in patients with small bowel Crohn's disease by double-balloon enteroscopy
Lifen YU ; Shidan CHENG ; Tianyu ZHANG ; Yonghua TANG ; Fei MIAO ; Jie ZHONG
Chinese Journal of Digestive Endoscopy 2014;(9):489-493
Objective To evaluate the clinical value of double-balloon enteroscopy( DBE)in as-sessing the effect of mucosal healing in patients with moderate small bowel Crohn's disease( CD)treated with low-dose azathioprine. Methods CD patients who were naive to any immunomodulators or biological a-gents with lesions mainly located in ileu were screened by multislice CT enterography and anal-route DBE at baseline. Lesions at 150 cm proximal to ileocecal valve were assessed by DBE with Simple Endoscopic Score for CD( SES-CD)after 12 and 24 months of low-dose azathioprine treatment,respectively. Results A total of 36 patients were enrolled and the average tolerated dose of azathioprine was(61. 8 ± 17. 2)mg/day. The total rates of complete,near-complete,partial and no mucosal healing in 36 patients were 19. 4%(7/36), 5. 6%(2/36),27. 8%(10/36),and 47. 2%(17/36)at month 12 and 30. 6%(11/36),25. 0%(9/36), 33. 3%(12/36),and 11. 1%(4/36)at month 24,respectively. The baseline SES-CD score(OR=2. 71, 95%CI:1. 11-6. 63,P=0. 029)and duration of disease(OR=1. 27,95%CI:1. 10-1. 47,P =0. 001) were two relevant factors associated with mucosal healing of small bowel CD. Conclusion DBE has a signif-icant advantage in assessing post-therapy mucosal healing for patients with small bowel CD. The optimal time point for the first follow-up by DBE is at least 12 months after low-dose azathioprine treatment.
3.Chromosome and plasmid-mediated quinolone resistance mechanism in clinical isolates of Serratia marcescens
Haifei YANG ; Xue ZHOU ; Jun CHENG ; Lifen HU ; Yulin ZHU ; Ying YE ; Jiabin LI
Chinese Journal of Laboratory Medicine 2012;35(8):706-710
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.
4.Distribution and resistance surveillance of 104 clinical strains of Serratia marcescens in Anhui Province
Jun CHENG ; Haifei YANG ; Yulin ZHU ; Lifen HU ; Yachao PAN ; Yanyan LIU ; Ying YE ; Jiabin LI
Chinese Journal of Infectious Diseases 2012;30(9):524-528
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.
5.The impact of double-balloon enteroscopy on the evolution of detection and surgical treatment for small bowel stromal tumors
Lifen YU ; Chenying XU ; Jie ZHONG ; Shidan CHENG ; Weiguo HU ; Yonghua TANG
Chinese Journal of Digestive Endoscopy 2013;30(5):257-260
Objective To investigate the role of double-balloon enteroscopy (DBE) in the evolution of detection and surgical treatment of small bowel stromal tumors (SBSTs),based on nine years experience.Methods In this retrospective study,193 patients with localized SBSTs were divided into the CT-enterography (CTE) and/or DBE group (n =100) and conventional modalities group (n =93).These patients were further divided into the open surgery group (n =126) and laparoscopy-assisted resection group (n =67).The development of clinical diagnosis and surgical treatment strategies were compared before and after the introduction of DBE.Results The average age and tumor size were significantly smaller in the CTE and/or DBE group than those in the conventional modalities group,respectively (age:50.9 ± 12.1 vs.56.9 ± 11.6 years; tumor size:3.6 ± 1.3 vs.6.1 ± 2.6 cm,P < 0.01).Before the introduction of DBE (from January 2001 to December 2002),all patients underwent conventional modalities,and only 4 cases/year for open surgery.Afterward,from January 2003 to December 2004,84.6% (11/13) of SBSTs were detected by DBE.From January 2005 to December 2008,50.0% (23/46) of SBSTs were found by CTE combination with DBE.From January 2009 to December 2011,80.5% (33/41) of SBSTs were diagnosed by CTE,and the number of patients underwent operation increased up to 25 cases/year,which was nearly 5.3 folds higher than that before the introduction of DBE.Sixty-seven patients were successfully operated by laparoscopy-assisted resection,82.1% (55/67) of them were detected by CTE ands/or DBE,89.1% (49/55) of whom had low-or intermediate-risk SBSTs.Conclusion DBE plays an important role in optimizing the algorithm of detection and treatment of SBSTs.
6.Detection of genotypes of plasmid-mediated quinolone resistance in clinical isolates of Shigella
Yanyan LIU ; Yachao PAN ; Lifen HU ; Jun CHENG ; Yulin ZHU ; Ying YE ; Jiabin LI
Chinese Journal of Infectious Diseases 2011;29(9):524-528
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.
7.Preliminary study of high-dose CT radiation injury on liver in rabbit models
Risheng YU ; Lirong CHEN ; Weimin ZHANG ; Wenhong DING ; Jianming HUA ; Lifen CHENG ; Jianzhong SUN ;
Chinese Journal of Emergency Medicine 2006;0(10):-
Objective To investigate acute CT radiation injury on rabbit liver after the whole body CT scans with high-dose abdominal CT scan model.Methods The forty-six New Zealand white rabbits were randomly assigned into 3 groups.High-dose CT scanning groups included one-off CT scanning group(group 1)and repeated CT scanning group (group 2)with high-dose abdominal CT scan modes,and 18 rabbits in each group.The other two groups were routine-dose CT scanning group(n=5)and control group(n=5).Rats in both group 1 and 2 were divided into 6 subgroups(n= 3).Four to twenty-four times of continuous or discontinuous CT scans with 240 mAs and 140 Kv were performed on every rabbit.The liver samples of every animal were eoUected at 48 h or 24 h after CT scans and pathological examination and immunohistochemistry assay of Cpp32 and Bax expression were performed.Results(1)Light microscope showed①in group 1,slight hepatic injury occurred at 6 times of continuous CT scanning;after 6~18 times of continuous CT scanning,hepatocytes were slight swelling at first,followed by hydropic or fatty degeneration,constriction or emphraxis of hepatic sinuses,puncture necrosis of hepatocytes,and local hepatic hemorrhage;②in group 2:slight hepatic injury occurred at 8 times of CT scanning,and after 8~24 times of CT scanning,hepatocytes were slight or mild swelling at first,followed by moderate or diffuse swelling,hydropic degeneration,and dispersed karyopyknosis of hepatocytes near central vein.(2)Immunohistochemistry assay showed:①in group 1,positive expressions of the apoptosis-inducing protein Bax and Cpp32 were observed in part of liver samples,the expressions of Bax and Cpp32 were correlated with CT radiation dose;②in group 2,positive expressions of the apoptosis-inducing protein Bax and Cpp32 were found in every subgroup,but the expression was not correlated with CT scan times.(3)The hepatic tissues of routine-dose CT scanning group were normal under the light microscope and immunohistochemistry assay.Conclusion Routine-dose CT scanning on liver is very safe,but high-dose CT scanning with non-routine scan times may cause acute pathological hepatic injury and hepatocyte apoptosis.
8.Comparison of diagnostic value of ultrasound,molybdenum target,magnetic resonance and single examination for breast cancer
Lifen ZHOU ; Fanghong CHEN ; Xue CHENG ; Yaqin FENG ; Lidan XIE
Chinese Journal of Primary Medicine and Pharmacy 2018;25(19):2504-2507
Objective To compare the diagnostic value of ultrasound,molybdenum target,magnetic resonance(MRI)and single examination for breast cancer.Methods From January 2017 to February 2018,100 patients with suspected breast cancer in Lishui Central Hospital were selected in the study.All patients were detected by ultrasound,mammography and MRI three ways for diagnosis.The results were verified with postoperative pathologic results as the standard.The diagnosis accuracy of three ways for breast cancer were analyzed.Results The detection accuracy of three ways joint detection in patients with breast cancer was the highest(91.00%),which was significantly higher than that of ultrasound(63.00%),mammography(72.00%)and MRI(72.00%)in single mode,the differences were statistically significant(χ2 =22.364,20.154,16.032,all P<0.05).Conclusion Ultrasonography,molybdenum target X ray and MRI have their respective advantages in the process of breast cancer differentiation and diagnosis,and the detection rate can be significantly improved if combined use.
9.Characterization of Extended-Spectrum β-Lactamase Genes of Shigella flexneri Isolates With Fosfomycin Resistance From Patients in China.
Yanyan LIU ; Yue CHENG ; Haifei YANG ; Lifen HU ; Jun CHENG ; Ying YE ; Jiabin LI
Annals of Laboratory Medicine 2017;37(5):415-419
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.
China*
;
Drug Resistance, Multiple
;
Dysentery, Bacillary
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Fosfomycin*
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Humans
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Plasmids
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Polymerase Chain Reaction
;
Public Health
;
Replicon
;
Shigella flexneri*
;
Shigella*
10.Surveillance of Antimicrobial Susceptibility Patterns among Shigella Species Isolated in China during the 7-Year Period of 2005-2011.
Haifei YANG ; Guosheng CHEN ; Yulin ZHU ; Yanyan LIU ; Jun CHENG ; Lifen HU ; Ying YE ; Jiabin LI
Annals of Laboratory Medicine 2013;33(2):111-115
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.
Adolescent
;
Adult
;
Aged
;
Aged, 80 and over
;
Ampicillin/pharmacology
;
Anti-Infective Agents/*pharmacology
;
Child
;
Child, Preschool
;
China
;
Drug Resistance, Bacterial/drug effects
;
Dysentery, Bacillary/*diagnosis/microbiology
;
Feces/microbiology
;
Humans
;
Infant
;
Microbial Sensitivity Tests
;
Middle Aged
;
Nalidixic Acid/pharmacology
;
Shigella/*drug effects/isolation & purification
;
Shigella flexneri/drug effects/isolation & purification
;
Shigella sonnei/drug effects/isolation & purification
;
Tetracycline/pharmacology
;
Time Factors
;
Trimethoprim-Sulfamethoxazole Combination/pharmacology
;
Young Adult