Prevalence and Antibiotic Resistance Pattern of <i>Escherichia coli</i>and <i>Klebsiella pneumoniae</i>in Urine Tract Infections at the La Paz Medical Center, Malabo, Equatorial Guinea

The study was conducted to isolate and determine the antibiotic resistance in Escherichia coli and Klebsiella pneumonia from urine samples over a 2-year period (August 2013-September 2015) at the La Paz Medical Center, Malabo. A retrospective analysis of 785 urine culture samples over a 2-year period August 2013-September 2015 was carried out according to the routine protocol of urinalysis. Bacterial etiological agents were isolated from 155 (19.7%) samples with highest prevalence of Escherichia coli (55.5%) followed by Klebsiella pneumonia (23.2%), Proteus mirabilis (4.5%), Pseudomonas species (3.2%), Enterobacter species (2.6%), Enterococcus faecalis (2.6%) and others species (8.4%). The E. coli and K. pneumonia represent 78.7% of all isolated bacterial strains. The E. coli and K. pneumoniae isolates possess highly resistant to ampicillin, Trimethoprim/Sulfamethoxazole, Doxycycline, Amoxicicline/Clavulanic acid. Whereas K. pneumonia demonstrated also to be highly resistant to Gentamycin, Cefuroxime and Ceftriaxon, low level of resistance to Piperacilin/Tazobactam, Amikacin and the lowest to Imipenem. The alarming level of MDR strains to the first choice antibiotics treatment was observed.

Multidrug Drug Resistance of Escherichia coli and Klebsiella Isolated from Iraqi Patients and Microbiota

Introduction: Escherichia coli and Klebsiella are Gram-negative bacilli of Enterobacteriaceae and are components of the colonic microbiota of animals and humans. The virulent strains cause gastroenteritis and urinary tract infections (UTI), and the incidence of the infections increases due to the increase of multidrug-resistant strains. The aim of this study is to determine the antibiotics resistance profile of E. coli and Klebsiella. Methodology: A total of 100 isolates of E. coli and Klebsiella were isolated from three sources, healthy stools and patient stools with gastroenteritis and urine subjects with UTI, during the period from November 2021 to January 2022. An antimicrobial susceptibility test was conducted with 14 antibiotics using the disc-Kirby-Bauer’s diffusion method. Results: Both E. coli and Klebsiella had variable abilities to resist the studied antimicrobial drugs, including 14 antibiotics belonging to nine different classes that have different patterns or mechanisms in stopping the growth or killing of microorganisms. All bacterial isolates revealed highly significant antimicrobial resistance almost for all antibiotics except carbapenems. About 72% of total isolates were multidrug-resistant (MDR), because they appeared resistant to at least three classes of antibiotics. Only two E. coli isolates out of 24 isolates (8.3%) were recovered from healthy stool samples and 6.25% of E. coli isolates (2 isolates out of 32) which were obtained from urine samples were sensitive to all antibiotics. The highest rates of antibiotic resistance were observed in E. coli than in Klebsiella. Both species had resistance to Amoxicillin-clavulanate (70.58%), Cefotaxime (58.96%), and Ceftazidime (57.81%). While the lowest frequency was meropenem (4.86%), and all strains were sensitive to imipenem (100%). Conclusion: These results partly explain the high prevalence of antibiotic resistance observed in Iraq due to drug misuse. Most of the bacterial strains were multidrug-resistant, and they spread more in pathogenic strains than in commensal strains.

Detection of Extended Spectrum β-Lactamase Producing Klebsiella pneumoniae and Escherichia coli in Two Hospitals in the Federal Capital Territory, Abuja, Nigeria

In this study, the prevalence of Extended Spectrum Beta-lactamase (ESBL) producing Klebsiella pneumoniae and Escherichia coli isolates from the University of Abuja Teaching Hospital and the National Hospital was determined. A total of two hundred and fifteen (215) clinical isolates were examined, of which 60% were E. coli and 40% K. pneumoniae respectively. The isolates were collected from various samples namely: Stool, Urine, Pus, High Vagina Swab, Sputum and Wound swab. Out of these isolates, 54 of K. pneumoniae were screened to be ESBL negative and 32 as ESBL positive isolates, while 88 and 40 E. coli were also screened as ESBL negative and ESBL positive isolates respectively. These represent 37.9% of all K. pneumoniae isolates and 31.25% of E. coli isolates respectively. The prevalence of ESBL among the species was not however statistically different (p > 0.05). Multiple resistance in these isolates was common and there is the need for routine screening of ESBL in our hospitals to guide rational and effective use of antibiotics.

CTX-M-14, CTX-M-24 and resistance in Escherichia coli and Klebsiella pneumoniae clinical isolates

Extended-spectrum β-lactamases （ESBLs） are the main cause of resistance to the third and forth-generation cephalosporins in Enterobacteriaceae, which are mediated by plasmids and can hydrolyze oxyiminoaminothiazolyl cephalosporins and monobactams. Most of ESBLs are mutants of the classical TEM and SHV types, with one or more amino-acid substitution（s） in the active site.

Emergence of Klebsiella pneumoniae carbapenemase-producing Escherichia coli sequence type 131 in Hangzhou, China

Background Klebsiella pneumoniae carbapenemase （KPC）-producing Escherichia （E.） coil has been reported in China since 2008.However,there is no information about the molecular epidemiology of KPC-producing E.coil in China.In this study,we aimed to investigate the sequence type （ST） and characteristics of KPC-producing E.coil isolates in China.Methods Three carbapenem-resistant isolates of E.coil （E1,E2,and E3） from one teaching hospital in Hangzhou covering a one year period were analyzed.Antibiotic susceptibility was determined by Etest.Pulsed-field gel electrophoresis （PFGE） and multilocus sequence typing （MLST） were used for epidemiological analysis.The genetic structure around blaKPC,the major plasmid incompatibility typing,and the identification of 3-lactamase gene types were performed by PCR and the positive products were subsequently sequenced.Plasmids were analyzed by transformation,restriction,and Southern blotting.Results PFGE demonstrated that patterns of isolates E1 and E2 were clonally-related and designated as patterns A1 and A2; pattern of isolate E3 was different and designated as pattern B.MLST analysis showed that the three isolates displayed one common sequence type ST131.The identification of bla gene types by PCR and sequencing showed that blaKPC-2,blaCTX-M-14,and blaTEM-1 were detected in all three isolates.All three isolates carried a KPC-2-encoding plasmid of the IncN replicon.Plasmid analysis and hybridization experiments showed that the isolates were found simultaneously to carry two or four plasmids.The blaKPc-2 gene in E1 and E2 was located in a plasmid with size of ca.50 kb.However,the blaKPC-2 gene in E3 was located in a plasmid with size of ca.130 kb.Conclusions E.coil ST131 with KPC-2 β-1actamase has emerged in China,which enlarges the geographical area where the ST131 KPC-oroducing E.coil strains have diffused.

Spreading of extended-spectrum β-lactamase-producing Escherichia coli ST131 and Klebsiella pneumoniae ST11 in patients with pneumonia a molecular epidemiological study

Background: Extended-spectrum β-lactamase (ESBL)-producing Escherichia coli (E. coli) and Klebsiella pneumoniae (K. pneumoniae) are the important pathogens causing pneumonia. This study aimed to investigate the clinical characteristics and molecular epidemiology of ESBL-producing E. coli and K. pneumoniae causing pneumonia at a large teaching hospital in China. Methods: We collected patient's clinical data and ESBL-producing E. coli and K. pneumoniae strains causing pneumonia (from December 2015 to June 2016) at a hospital in Wuhan. The susceptibilities, multi-locus sequence typing, homologous analysis, ESBL genes by polymerase chain reaction and sequencing were determined. Results: A total of 59 ESBL-producing strains (31 E. coli and 28 K. pneumoniae) isolated from patients with pneumonia were analyzed. The majority of strains were isolated from patients were with hospital-acquired pneumonia (37/59, 62.7%), followed by community-acquired pneumonia (13/59, 22.0%), and ventilator-related pneumonia (9/59, 15.3%). The E. coli ST131 (9 isolates, 29.0%) and K. pneumoniae ST11 (5 isolates, 17.9%) were the predominant sub-types. The most prevalent ESBL gene was CTX-M-14, followed by SHV-77, CTX-M-3, SHV-11, and CTX-M-27. At least 33 (55.9%) of the ESBL-producing strains carried two or more ESBL genes. The ISEcp1 and IS26 were found upstream of all blaCTX-M (CTX-Ms) and of most blaSHV (SHVs)(57.6%), respectively. Moreover, three ESBL-producing K. pneumoniae ST11 strains which were resistant to carbapenems carried the blaNDM-1 and blaKPC-2, two of which also bearing blaOXA-48 were resistant to all antibiotics (including Tigecycline). Conclusions: Hospital-acquired pneumonia is more likely correlated with ESBL-producing E. coli and K. pneumoniae. ESBL-producing E. coli ST131 and multi-drug resistance ESBL-producing, as well as New Delhi metallo-β-lactamase-1 (NDM-1) and Klebsiella pneumoniae carbapenemases-2 (KPC-2) bearing K. pneumoniae ST11 are spreading in patients with pneumonia in hospital.

Impact of Polymyxin Resistance on Virulence and Fitness among Clinically Important Gram-Negative Bacteria

Humanity is facing an enormous and growing worldwide threat from the emergence of multi-drug-resistant(MDR)Gram-negative bacteria such as Escherichia coli,Klebsiella pneumoniae,and Acinetobacter baumannii.Polymyxin B and E(colistin)constitute the last-line therapies for treating MDR Gram-negative bacteria.Polymyxin is a cationic antibacterial peptide that can destroy the outer membrane of Gram-negative bacteria.With the increasing clinical application of polymyxin,however,there have been many reports of the occurrence of polymyxin-resistant Gram-negative bacteria.This resistance is mainly mediated by the modification or complete loss of lipopolysaccharide(LPS).LPS is also a virulence factor of Gram-negative bacteria,and alterations of LPS may correlate with virulence.Although it is generally believed that the biological costs associated with drug resistance may enable benign susceptible bacteria to overcome resistant bacteria when antibiotic pressure is reduced,some studies have shown that polymyxin-resistant bacteria are associated with higher virulence and greater fitness compared with their susceptible counterparts.To predict the development of polymyxin resis-tance and evaluate interventions for its mitigation,it is important to understand the relative biological cost of polymyxin resistance compared with susceptibility.The impact of polymyxin resistance mecha-nisms on the virulence and fitness of these three Gram-negative bacteria are summarized in this review.

Health care associated infections, antibiotic resistance and clinical outcome: A surveillance study from Sanandaj, Iran

AIM: To study the antibiotic susceptibility patterns of gram-negative healthcare associated bacterial infections at two tertiary hospitals in the Sanandaj city, Kurdistan Province, Iran.METHODS: From January 2012 to December 2012, all positive cultures from potentially sterile body fluids were gathered. They sent to professor Alborzi clinical microbiology center in Shiraz for further analysis and susceptibility testing. The antibiotic susceptibility was determined using the Kirby-Bauer method(disk diffusiontechnique). The Results were interpreted according to Clinical and Laboratory Standards Institute guidelines against a series of antimicrobials. World Health Organization definitions for Healthcare associated infections were followed.RESULTS: Seven hundred and thirty-two positive cultures were reported from both hospitals. Seventynine isolates/patients fulfilled the study criteria for healthcare associated gram-negative infections. The most frequent bacterial cultures were from the pediatric wards(52%). Serratia marcescens(S. marcescens)(38%) Escherichia coli(E. coli)(19%), Klebsiella pneumoniae(K. pneumoniae)(19%), Acinetobacter baumannii(6%), Enterobacter species(6%), Serratia odorifera(4%) and Pseudomonas species(5%) were the most frequently isolated organisms. The susceptibility pattern of common isolates i.e., S. marcescens, E. coli and K. pneumoniae for commonly used antibiotics were as follows: Ampicillin 3.3%, 6.7%, 20%; gentamicin 73.3%, 73.3%, 46.7%; ceftazidim 80%, 73.3%, 33.3%; cefepim 80%, 86.7%, 46.7%; piperacillin/tazobactam 90%, 66.7%, 86.7%; ciprofloxacin 100%, 73.3%, 86.7%; imipenem 100%, 100%, 100%, respectively. CONCLUSION: The most effective antibiotics against gram-negative healthcare associated infections are imipenem followed by ciprofloxacin. The resistance rate is high against ampicillin and cephalothin. The high mortality rate(46.1%) associated with S. marcescens is alarming.

Increased clonal dissemination of OXA-232-producing ST15 Klebsiella pneumoniae in Zhejiang,China from 2018 to 2021

Background OXA-232-producing Klebsiella pneumoniae was first identified in China in 2016,and its clonal transmission was reported in 2019.However,there are no prevalence and genotypic surveillance data available for OXA-232 in China.Therefore,we investigated the trends and characteristics of OXA-232 type carbapenemase in Zhejiang Province,China from 2018 to 2021.Methods A total of 3278 samples from 1666 patients in the intensive care units were collected from hospitals in Zhejiang Province from 2018 to 2021.Carbapenem-resistant isolates were initially selected by China Blue agar plates supplemented with 0.3μg/ml meropenem,and further analyzed by matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry identification,immune colloidal gold technique,conjugation experiment,antimicrobial susceptibility testing and whole genome sequencing.Results A total of 79 OXA-producing strains were recovered,with the prevalence increased from 1.8%[95%confidence interval(CI):0.7–3.7%]in 2018 to 6.0%(95%CI:4.4–7.9%)in 2021.Seventy-eight strains produced OXA-232 and one produced OXA-181.The blaOXA-232 gene in all strains was located in a 6141-bp ColKP3-type non-conjugative plasmid and the blaOXA-181 gene was located in a 51,391-bp ColKP3/IncX3-type non-conjugative plasmid.The blaOXA-232-producing K.pneumoniae was dominated(75/76)by isolates of sequence type 15(ST15)that differed by less than 80 SNPs.All OXA-producing strains(100%,95%CI:95.4–100.0%)were multidrug-resistant.Conclusions From 2018 to 2021,OXA-232 is the most prevalent OXA-48-like derivative in Zhejiang Province,and ST15 K.pneumoniae isolates belonging to the same clone are the major carriers.The transmission of ColKP3-type plasmid to E.coli highlighted that understanding the transmission mechanism is of great importance to delay or arrest the propagation of OXA-232 to other species.

肾移植术后尿路感染209例的临床特点及危险因素分析

目的探讨肾移植术后不同时期尿路感染的特点及其相关危险因素。方法回顾性分析209例肾移植受者的临床资料,按照术后随访时间分为3个时期,第一时期为移植术后1个月内,第二时期为术后1~6个月,第三时期为术后7~12个月。分析肾移植术后不同时期尿路感染的发生情况,发生尿路感染受者的尿培养结果及常见病原菌耐药特点。分析反复尿路感染者的菌群,分析尿路感染的危险因素及尿路感染对移植肾功能的影响。结果第一时期尿路感染率为90.0%,第二时期尿路感染率为49.3%,第三时期尿路感染率为22.5%。第二时期、第三时期亲属活体器官捐献男性受者的尿路感染率低于女性受者(均为P<0.05)。尿培养结果阳性60例,共检出病原菌84株,以革兰阴性菌为主,其中肺炎克雷伯菌占比最高。66例受者反复发生尿路感染,检出病原菌包括肺炎克雷伯菌、大肠埃希菌、光滑假丝酵母菌和其他。单因素分析结果显示,术后使用抗胸腺细胞球蛋白是第一时期发生尿路感染的危险因素,术前尿路感染、供者类型是第二时期发生尿路感染组的危险因素,受者性别、年龄是第三时期发生尿路感染的危险因素;多因素分析结果显示,术后使用抗胸腺细胞球蛋白是第一时期发生尿路感染的危险因素,受者性别、年龄是第三时期发生尿路感染的危险因素(均为P<0.05)。第三时期治愈65例,未治愈38例,治愈患者治疗后血清肌酐及白细胞水平较治疗前下降(均为P<0.05)。结论肾移植受者尿路感染以革兰阴性菌为主,其耐药性较高;术后使用抗胸腺细胞球蛋白、女性和高龄是肾移植受者发生尿路感染的危险因素。

Comparative antimicrobial activity in Murrah buffalo (Bubalus bubalis) Heifers’ urine and urine distillate

Background:Murrah buffalo is a breed of water buffalo(Bubalus bubalis)reared for milk and meat,especially in Northern India.There are so many studies on the antimicrobial potential of the cow(Bos indicus)urine but buffalo urine has rarely been studied.This study was aimed to evaluate the antimicrobial activity in whole buffalo urine and its distillate.Methods:Urine specimens were collected from seven Murrah buffalo heifers in the morning over three days from all seven heifers and distillated to prepare urine distillate(UD).The antimicrobial activity was determined through 96 well microplate method diluting(1:1)urine and UD in Mueller Hinton liquid medium against 919 microbial strains belonging to 148 species of 49 genera(Candia,11 genera of Gram+ve bacteria,37 genera of Gram-ve bacteria).The test strains were taken from the repository,revived and tested for purity before testing.The test strains were of clinical origin(372),environmental origin(496)and also from reference strain repositories(51).Results:Of the 919 test strains,a total of 57.89%and 56.04%of the tested strains were susceptible to UD and urine,respectively.There was a no significant(p>0.4)difference in the antimicrobial activity of UD and urine against 919 strains of microbes,regardless of their genus,species,and Gram staining reaction.Similarly,there was no significant(p>0.4)difference between the susceptibility of bacterial and Candida strains to UD or urine.However,strains of clinical origin were more often resistant to buffalo UD and urine(p<0.01)than strains isolated from environmental sources irrespective of their Gram staining characteristics(p>0.05).A significantly(p<0.01)higher proportion of reference strains was susceptible to UD and urine than microbial strains of clinical and environmental origin.For buffalo urine and UD,the most susceptible strains were Stenotrophomonas maltophilia(13/13)followed by Citrobacter freundii(8/10);Salmonella enterica ssp.enterica(21/27),Geobacillus stearothermophilus(23/30),Staphylococcus aureus(13/17),and Paenibacillus larvae(7/10)strains.The most resistant strains belonged to Acinetobacter calcoaceticus(15/20)species followed by strains of Paenibacillus alvei(11/16),Edwardsiella tarda(20/30),Bacillus megaterium(7/11)and Escherichia coli(59/110)species.There was insignificant(p,>0.05)difference in susceptibility of strains of different species of the same genus;however,among all the Bacillus species strains of B.coagulans were the most susceptible(66.7%)and strains of B.megaterium were the least susceptible(36.4%),similarly Enterococcus faecium strains were more susceptible(68.2%)than strains of Enterococcus faecalis(38.9%),70%strains of P.larvae were susceptible to urine and UD but only 31.3%of strains of P.alvei were susceptible.Strains of Klebsiella pneumoniae and Raoultella terrigena,earlier belonging to the same genus Klebsiella,had comparable susceptibility to buffalo urine and UD.Conclusion:The study concluded that buffalo urine may be a potential antimicrobial and may be explored further for identification of active antimicrobial compounds in buffalo urine.

医院肠杆菌科细菌耐药率与抗菌药使用强度的相关性

目的分析近7年大肠埃希菌及肺炎克雷伯菌耐药率与抗菌药物使用强度(antibiotics use density,AUD)的相关性,为临床合理使用抗菌药物提供参考。方法回顾性分析该院2016—2022年大肠埃希菌及肺炎克雷伯菌的耐药率与同期主要抗菌药物的AUD,采用Pearson相关性分析法分析两者的相关性。结果大肠埃希菌对对哌拉西林/他唑巴坦的耐药率与头孢呋辛的AUD呈正相关(P<0.05);对头孢吡肟的耐药率与头孢西丁、氨曲南的AUD呈正相关(P<0.01、P<0.05);对头孢西丁的耐药率与头孢西丁的AUD呈正相关(P<0.05);对亚胺培南的耐药率与头孢哌酮/舒巴坦、阿米卡星的AUD呈正相关(P<0.01)。肺炎克雷伯菌对阿莫西林/克拉维酸的耐药率与头孢西丁、氨曲南的AUD呈正相关(P<0.01);对哌拉西林/他唑巴坦的耐药率与头孢西丁的AUD呈正相关(P<0.05),对头孢噻肟的耐药率与阿莫西林/克拉维酸的AUD呈正相关(P<0.01);对头孢吡肟的耐药率与头孢西丁、左氧氟沙星的AUD呈正相关(P<0.05);对阿米卡星的耐药率与头孢他啶、头孢噻肟、亚胺培南的AUD呈正相关(P<0.01、P<0.05)。大肠埃希菌对哌拉西林/他唑巴坦的耐药率与头孢唑啉的AUD呈负相关(P<0.05);对头孢唑啉的耐药率与头孢他啶、头孢噻肟的AUD呈负相关(P<0.05);对头孢吡肟的耐药率与哌拉西林/他唑巴坦、头孢噻肟的AUD呈负相关(P<0.05);对头孢西丁的耐药率与头孢噻肟的AUD呈负相关(P<0.05);对亚胺培南的耐药率与阿莫西林/克拉维酸的AUD呈负相关(P<0.05)。肺炎克雷伯菌对阿莫西林/克拉维酸的耐药率与哌拉西林/他唑巴坦的AUD呈负相关(P<0.05);对头孢西丁的耐药率与哌拉西林/他唑巴坦的AUD呈负相关(P<0.05)。结论大肠埃希菌及肺炎克雷伯菌的耐药率与多种抗菌药物的AUD相关,应加强抗菌药物的合理管控,延缓细菌耐药的发生。

多学科综合诊疗模式在肺移植受者多重耐药菌感染防控的应用

目的 探讨多学科综合诊疗(MDT)模式在肺移植受者术后多重耐药菌(MDRO)感染防控中的实践效果。方法 选择2019年至2022年的肺移植受者,从2020年1月开始成立MDT专家组,开展一系列防控措施,分析2020年至2022年MDRO防控措施落实率、环境物表MDRO检出率以及2019年至2022年肺移植受者MDRO检出率。结果 医护人员总体MDRO防控措施落实率由2020年的64.9%上升至2022年的91.6%,呈逐年升高趋势(P<0.05)。监测环境物表MDRO检出率从2020年的28%下降到2022年的9%,呈逐年下降趋势(P<0.05)。肺移植受者MDRO检出率从2019年的66.7%降低至2022年的44.3%,呈逐年降低趋势(P<0.001)。结论 通过MDT模式管理,提高了医务人员MDRO防控措施的执行力,有效降低了肺移植受者术后MDRO感染率和环境物表MDRO检出率,值得推广利用。

某三甲医院2017-2022年常见G^(-)菌的分布及耐药性分析

目的 分析2017-2019年和2020-2022年我院革兰阴性(G^(-))菌的病原菌分布、细菌耐药情况,为临床合理地应用抗菌药物提供参考依据。方法 采用回顾性分析2017-2019年和2020-2022年我院的各类送检标本,采用专业认可的鉴定系统或手工方法进行细菌鉴定和耐药性检测,应用Whonet5.6软件进行数据分析。结果 共检出革兰阴性菌14421株,痰液标本最常见。2017-2019年我院分离的G^(-)菌居前5位者为大肠埃希菌、肺炎克雷伯菌、鲍曼不动杆菌、铜绿假单胞菌、阴沟肠杆菌。2020-2022年我院分离的G^(-)菌居前5位者为肺炎克雷伯菌、大肠埃希菌、鲍曼不动杆菌、铜绿假单胞菌、阴沟肠杆菌。两组主要标本来源均为痰、尿液和分泌物。2020-2022年和2017-2019年相比,大肠埃希菌和肺炎克雷伯菌对多数抗生素的耐药率呈下降趋势(P<0.05);肺炎克雷伯菌对环丙沙星的耐药率呈上升趋势(χ^(2)=6.045,P<0.05);2020-2022年和2017-2019年相比,鲍曼不动杆菌对左氧氟沙星耐药率呈上升趋势(χ^(2)=18.328,P<0.05),对氨基糖苷类庆大霉素和妥布霉素耐药率呈下降趋势(χ^(2)=46.647,χ^(2)=31.780,P均<0.05);铜绿假单胞菌对头孢他啶、喹诺酮类环丙沙星和左氧氟沙星耐药率呈上升趋势(χ^(2)=8.201,χ^(2)=4.298,χ^(2)=15.032,P均<0.05),对β-内酰胺类亚胺培南和美罗培南耐药率呈下降趋势(χ^(2)=26.089,χ^(2)=24.966,P均<0.05);阴沟肠杆菌对头孢呋辛钠耐药率呈下降趋势(χ^(2)=121.541,P<0.05)。结论 2020-2022年和2017-2019年相比,我院部分G^(-)菌对一些抗菌药物的耐药率有所下降,但总体G^(-)菌的耐药形势仍然十分严峻,需定期进行细菌耐药性监测。

抗菌涂料抗菌性能测定方法的扩展与分析

为更好分析不同抗菌涂料对多种细菌的抗菌效果,先利用梯度稀释法确定四种细菌菌液的适宜测试浓度,消除菌液丰度的影响,然后按《抗菌涂料(漆膜)抗菌性测定法和抗菌效果》(GB/T 21866—2008)与《食品卫生微生物学检验菌落总数测定》(GB/T 4789.2—2016)等标准方法,测定了硅酸盐和竹炭两种类型抗菌涂料对大肠杆菌、金黄色葡萄球菌、肺炎克雷伯氏菌、铜绿假单胞菌的抗菌性能及其耐久性.结果表明,菌悬液制备过程中菌落的适宜计数稀释梯度均为10^(-5)和10^(-6);在24 h后两种抗菌涂料对4种细菌的抗菌率和抗菌耐久性分别达到99.35%和98.18%以上,对比非抗菌涂料,抗菌性能达到Ⅰ级标准.两种抗菌涂料均适用于医院、幼儿园等公共卫生条件要求较高的场所.

某院临床分离肠杆菌科细菌分布特征及其耐药性分析

目的 分析某院临床分离肠杆菌科细菌分布特征及其耐药性。方法 82株肠杆菌科细菌分离自2021年1月-2022年12月于我院治疗患者的血、尿、痰、大便及分泌物等标本。采用全自动微生物鉴定仪进行病原菌种类鉴定,采用纸片扩散法及琼脂平板稀释法进行药敏鉴定。结果 82株病原菌中大肠埃希菌有33株,占比40.24%;肺炎克雷伯菌29株,占比35.37%,肠杆菌10株,占比12.20%,变形杆菌10株,占比变形杆菌12.20%;82株病原菌中痰液标本来源有50株,占比60.98%(50/82);血标本来源17株,占比20.73%(17/82);尿液标本来源11株,占比13.41%(11/82),分泌物及大便标本来源各有3株、1株;大肠埃希菌ESBLs检出31株(93.94%),CRE检出2株(6.06%);肺炎克雷伯菌MDR检出26株(89.66%),CRE检出3株(10.34%);肠杆菌MDR检出7株(70.00%),CRE检出3株(30.00%);变形杆菌MDR检出10株(100.00%);大肠埃希菌对厄他培南、亚胺培南、美罗培南、阿米卡星、头孢哌酮/舒巴坦耐药率较低(耐药率均≤10%);肺炎克雷伯菌对厄他培南、亚胺培南、美罗培南、阿米卡星、哌拉西林/他唑巴坦、头孢哌酮/舒巴坦耐药率较低(耐药率均≤10%);肠杆菌、变形杆菌均对厄他培南、亚胺培南、美罗培南、阿米卡星耐药率较低(耐药率均≤10%);肠杆菌科细菌对氨苄西林/舒巴坦、头孢曲松、头孢呋辛、头孢唑林、氨苄西林耐药率均较高(耐药率>50%)。结论 某院临床分离肠杆菌科细菌以大肠埃希菌、肺炎克雷伯菌最为常见,痰液、血液为肠杆菌科细菌标本主要来源,肠杆菌科细菌的ESBLs、MDR检出率较高,需要依据药敏结果合理使用抗菌药物。

肠杆菌科细菌感染的耐药性分析及其分布特点研究

目的:探讨肠杆菌科细菌感染的耐药性及其临床分布特点,为临床诊治肠杆菌科细菌感染提供参考。方法:选择2019年1月—2023年6月苏州市吴中区第二人民医院临床分离的肠杆菌科细菌800株作为研究对象。对800株肠杆菌科细菌予以全自动微生物分析仪鉴定菌株情况,并实施药敏试验,总结肠杆菌科细菌临床分布特点,分析其药敏性。结果:经菌株鉴定发现,800份菌株中,肺炎克雷伯菌占比最多(300株),大肠埃希菌次之(220株),之后为肠杆菌属(包括阴沟肠杆菌与产气肠杆菌,共120株)。相关科室分离出的肠杆菌科细菌中,来自综合内科的最多,共140株。药敏试验结果显示,肺炎克雷伯菌主要对氨苄西林耐药,大肠埃希菌主要对氨苄西林、复方新诺明、环丙沙星、哌拉西林、四环素耐药,肠杆菌则主要对氨苄西林、阿莫西林/克拉维酸耐药。结论:肠杆菌科细菌感染中肺炎克雷伯菌、大肠埃希菌、阴沟肠杆菌、产气肠杆菌比较常见,以肺炎克雷伯菌、大肠埃希菌占比较高,临床需做好这些菌种的耐药性分析,为临床治疗提供参考,从而提高临床抗肠杆菌科细菌感染的治疗效果。

1例卒中相关性肺炎老年患者抗感染治疗的实践体会

目的:分析1例卒中相关性肺炎老年患者抗感染治疗的治疗过程,为临床类似患者的抗感染治疗提供参考。方法与结果:患者因“左侧肢体无力,意识不清,伴肢体抽搐4 d”收治入院,结合其头颅CT检查结果,初步诊断为卒中,而其胸部CT结果提示存在肺部感染,考虑为卒中相关性肺炎,遂经验性予头孢他啶治疗;4 d后,痰标本中检出肺炎克雷伯菌(超广谱β-内酰胺酶检查呈阴性);又6 d后,患者突发高热,且白细胞计数、中性粒细胞百分比、C反应蛋白等感染指标明显升高,遂将头孢他啶改为亚胺培南-西司他丁钠,但感染症状并未明显好转;又3 d后,痰标本中检出金黄色葡萄球菌(对甲氧西林耐药),遂建议加用万古霉素;又6 d后,感染仍未明显消退,遂将万古霉素调整为利奈唑胺,但感染仍不时反复;之后,痰标本中检出大肠埃希菌(超广谱β-内酰胺酶检查呈阳性),遂予哌拉西林-他唑巴坦钠;3 d后,患者感染基本消退,遂出院。结论:卒中相关性肺炎具有病原菌谱复杂、混合感染多久的特点,并且疾病过程中病原菌往往多变;对此,临床药师应积极探寻卒中相关性肺炎的病原菌,从而及时予以针对性抗感染治疗,以确保患者尽快康复。

不同地区儿童社区获得性肺炎常见革兰阴性菌对碳青霉烯类药物的耐药性差异及变迁

目的 比较不同地区儿童社区获得性肺炎(community-acquired pneumonia,CAP)的痰液培养中常见革兰阴性菌对碳青霉烯类药物的耐药性差异及变迁,为医疗援助提供参考。方法 回顾性研究2019年6月至2022年6月湖州和安顺地区CAP患儿的痰液培养及药敏结果,分析历年常见革兰阴性菌对碳青霉烯类药物的耐药性,比较不同地区间差异及历年耐药性变迁。结果 近3年两个地区痰液培养常见革兰阴性菌为肺炎克雷伯菌、大肠埃希菌。湖州地区肺炎克雷伯菌检出率在2019、2021年明显高于安顺地区(P<0.05),耐药率2019年明显高于安顺地区(P<0.05),2021年低于安顺地区(P<0.05);湖州地区肺炎克雷伯菌耐药率逐年降低,2021年明显低于2019年(P<0.05),安顺地区逐年升高,2021年明显高于2019年(P<0.05)。对于大肠埃希菌,湖州地区检出率在近3年中均明显低于安顺地区(P<0.05),其耐药率在同一年不同地区以及同一地区近3年的变迁比较,差异无统计学意义(P>0.05)。结论 儿童CAP常见革兰阴性菌对碳青霉烯类药物的耐药性在不同地区具有差异,并逐年变化,在医疗援助中,依据本地区经验的同时,更要根据受援医院的细菌耐药性监测系统,结合当地情况选用抗菌药物。

某院新生儿肠杆菌感染败血症耐药性及其抗菌药物治疗分析

目的 对新生儿肠杆菌感染败血症耐药性和抗菌药物治疗进行分析,旨在为临床用药提供参考。方法 回顾性分析武汉大学人民医院2020年1月—2021年12月新生儿科诊断为败血症且血培养肠杆菌的住院患儿,对患儿的一般临床特征、病原菌、药敏试验结果、产酶类型以及患儿的治疗方案及临床结局进行收集统计。结果 共收集肠杆菌感染败血症患儿30例,主要病原菌为大肠埃希菌与肺炎克雷伯菌,大肠埃希菌主要耐药机制为耐碳青霉烯酶,且以产B类金属β-内酰胺酶型为主,主要治疗方案为氨曲南单药治疗;肺炎克雷伯菌主要耐药机制为产超广谱β-内酰胺酶,主要治疗药物为碳青霉烯抗菌药物,接受治疗的患儿均取得较好的治疗效果。结论 耐碳青霉烯大肠埃希菌推荐给予氨曲南治疗,产超广谱β-内酰胺酶的肺炎克雷伯菌可优先给予碳青霉烯类抗菌药物,本研究可为临床多重耐药肠杆菌感染败血症新生儿提供用药参考。