Low-Level Antibiotic Resistance among Staphylococcus aureus and Gram-Negative Pathogens from Infected Skin and Soft Tissues in Rural Kenya

Introduction: Bacterial skin and soft tissue infections (SSTIs) are a cause of frequent inpatient and outpatient care visits whose causative agents are associated with a high antimicrobial resistance burden. For insights on antimicrobial susceptibilities in a rural setting, we examined specimens from suspected SSTIs from two public health facilities in Kenya. We additionally assessed antibiotic use, appropriateness of empiric therapy and risk factors for SSTI. Methodology: Between 2021 and 2023, 265 patients at Kisii and Nyamira County Referral hospitals were enrolled. Wound swabs/aspirates were collected and processed following standard microbiological procedures. Identification and antimicrobial susceptibility were performed using the VITEK 2 Compact platform. Demographic, clinical, and microbiological data were analyzed with R Statistical software. Results: S. aureus was isolated in 16.2% (43/265) of patients with a methicillin resistance (MRSA) proportion of 14% (6/43). While 13/15 drugs elicited susceptibilities ranging from 84% - 100%, penicillin (16%) and trimethoprim-sulfamethoxazole [TMP-SXT] (23%) yielded the lowest susceptibilities. Escherichia coli (n = 33), Klebsiella pneumoniae (n = 8), Pseudomonas aeruginosa (n = 8), and Citrobacter species (n = 4) were the most commonly isolated gram-negative species. Gram-negative strains showed high susceptibilities to most of the tested drugs (71% - 100%) with the exception of ampicillin (18%), TMP-SXT (33%), and first and second generation cephalosporins. Conclusions: The low MRSA prevalence and generally high antibiotic susceptibilities for S. aureus and gram-negative bacteria present opportunities for antibiotic stewardship in the study setting. Diminished susceptibilities against penicillin/ampicillin and TMP-SXT accord with prevailing local data and add a layer of evidence for their cautious empiric use.

Occurrence of tetracycline residues and antimicrobial resistance in gram negative bacteria isolates from cattle farms in Spain

The usage of antibiotics in animal husbandry has dramatically increased the concentration of antibiotic residues and has promoted the development and abundance of antibiotic resistance in manure. When it is spread onto agricultural land, both residues of antibiotics and bacteria carrying antibiotic resistance genes may be introduced into the environment. In this research, we isolated resistant gram negative bacteria from manure produced in two dairy and two beef cattle farms, located in Madrid (Spain), to determine their resistance to seventeen representative antibiotics commonly used in veterinary therapy. A total of 63 isolates were used to assess the overall bacterial antimicrobial resistance on cattle manure samples. Predominant species were Escherichia coli and Comamonas testosteroni accounting for 25% and 19.6% of the total, respectively. The most found antimicrobial resistances in gram-negative bacteria were to tetracycline (66.7%), sulphamethoxazole (55.6%), ampicillin (52.4%), cephalothin (46.0%), chloramphenicol (44.4%), nalidixic acid (39.7%) and trimethroprim- sulphamethoxazole (33.3%). The mean of resistance and the percentage of multi-resistant bacteria in beef farms were higher and statistically significant when compared to dairy farms which is opposite from the findings of the previous studies. The presence of three tetracyclines in all manure samples was also examined with stable recoveries (76% - 82%) and high sensitivity (limit of quantification 0.015 - 0.03 μg/kg). The concentrations of tetracyclines detected (<0.015 - 10 mg/kg) were consistent to the theoretical tetracycline levels in manure in Spain according to the ex- cretion rate of these antibiotics and the values re-ported in scientific literature in other European coun- tries.

pLoc_Deep-mGneg: Predict Subcellular Localization of Gram Negative Bacterial Proteins by Deep Learning

The recent worldwide spreading of pneumonia-causing virus, such as Coronavirus, COVID-19, and H1N1, has been endangering the life of human beings all around the world. In order to really understand the biological process within a cell level and provide useful clues to develop antiviral drugs, information of Gram negative bacterial protein subcellular localization is vitally important. In view of this, a CNN based protein subcellular localization predictor called “pLoc_Deep-mGnet” was developed. The predictor is particularly useful in dealing with the multi-sites systems in which some proteins may simultaneously occur in two or more different organelles that are the current focus of pharmaceutical industry. The global absolute true rate achieved by the new predictor is over 98% and its local accuracy is around 94% - 100%. Both are transcending other existing state-of-the-art predictors significantly. To maximize the convenience for most experimental scientists, a user-friendly web-server for the new predictor has been established at http://www.jci-bioinfo.cn/pLoc_Deep-mGneg/, which will become a very useful tool for fighting pandemic coronavirus and save the mankind of this planet.

An Improved Approach for Rapidly Identifying Different Types of Gram-Negative Bacterial Secreted Proteins

Protein secretion plays an important role in bacterial lifestyles. In Gram-negative bacteria, a wide range of proteins are secreted to modulate the interactions of bacteria with their environments and other bacteria via various secretion systems. These proteins are essential for the virulence of bacteria, so it is crucial to study them for the pathogenesis of diseases and the development of drugs. Using amino acid composition (AAC), position-specific scoring matrix (PSSM) and N-terminal signal peptides, two different substitution models are firstly constructed to transform protein sequences into numerical vectors. Then, based on support vector machine (SVM) and the “one to one”?algorithm, a hybrid multi-classifier named SecretP v.2.2 is proposed to rapidly and accurately?distinguish different types of Gram-negative?bacterial secreted proteins. When performed on the same test set for a comparison with other methods, SecretP v.2.2 gets the highest total sensitivity of 93.60%. A public independent dataset is used to further test the power of SecretP v.2.2 for predicting NCSPs, it also yields satisfactory results.

Diagnostic Validity of Cica Beta Test 1 for the Detection of Extended Spectrum Beta-Lactamase (ESBL) Producing Gram Negative Bacteria by Comparing with Phenotypic Method

Background: Detection of extended spectrum beta lactamase producing bacteria is an important issue in the clinical settings. Objective: The purpose of the present study was to validate the Cica Beta Test 1 for detection of extended spectrum beta-lactamase (ESBL) producing bacteria. Method: This analytical type of cross-sectional study was carried out in the Department of Microbiology and Immunology at Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka from January 2006 to December 2006 for a period of one (01) year. All the patients presented with the clinical features of urinary tract infection and surgical as well as burn wound infection at any age with both sexes were selected as study population. All bacteria were isolated and identified by their colony morphology, staining characters, pigment production, motility and other relevant biochemical tests. Phenotypic confirmation of ESBLs producing isolates were done by inhibitor potentiated disc diffusion test according to CLSI recommendation. The Cica Beta Test 1 was performed according to the manufacturer’s instructions. Result: A total number of 288 Gram negative bacteria were isolated. Among these isolates Cica Beta test 1 was positive in 97 strains and phenotypic confirmatory test was positive in 89 strains. The test sensitivity of Cica Beta Test 1 was 100% (95% CI 95.9% to 100.0%). Specificity of the test was 96.0% (95% CI 92.2% to 98.2%). The positive predictive value (PPV) and negative predictive value (NPV) were 92.7% (95% CI 84.5% to 95.7%) and 100.0% (95% CI 98.0% to 100.0%) respectively. The accuracy of the test was 97.2% (95% CI 95.1% to 99.1%). Area under ROC curve = 0.980 (95% CI 0.964 to 0.996);p value 0.0001. Conclusion: In conclusion, Cica Beta Test 1 is very high sensitivity and specificity for the detection of ESBL from Gram negative bacteria.

Multiple Antibiotic Resistant Index of Gram-Negative Bacteria from Bird Droppings in Two Commercial Poultries in Enugu, Nigeria

Antimicrobial resistance refers to the ability of microorganisms to grow in the presence of an antimicrobial agent at a concentration that will normally kill or inhibit their growth. Antimicrobial resistance has become a major global threat making treatment of infections tougher especially with high cost of treatment in humans and animals. This study was done to determine the Multiple Antibiotic Resistant Index (MARI) of Gram-negative bacteria from bird droppings in two commercial poultries in Enugu. Forty (40) samples were collected from each of the poultries. Isolates were identified by standard microbiological methods. The isolates identified were Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Citrobacter spp, Proteus spp. and, Enterobacter spp. Antibiotic susceptibility testing was carried out using disc diffusion technique. The organisms were tested against pefloxacin, augmentin (amoxicillin and clavulanic acid), ceftazidime, streptomycin, ciprofloxacin, gentamycin, cephalothin, neomycin and ofloxacin. The result of the susceptibility test showed that Proteus spp had the highest resistance and MARI value of 0.5 and 1.0 respectively. The other MARI values were Escherichia coli (0.9), Klebsiella pneumonia (0.9), Pseudomonas aeruginosa (0.8), Citrobacter spp (0.8) and Enterobacter spp (0.7). These results suggest that bacterial organisms from poultry source can contribute significantly to the spread of multi-antibiotic resistant organisms. This could arise from the indiscriminate use of antibiotics in bird feeds in poultries.

Review: Gram Negative Bacteria in Brewing

Gram negative aerobic bacteria such as Acetic Acid Bacteria, which include Acetobacter and Gluconobacter, have historically caused significant problems to brewers. Although incidences of spoilage have recently reduced as a result of improvements in beer packaging, these bacteria are still a concern in dispense systems in pub breweries, public houses and cask conditioned beers. Gram negative facultative bacteria of the genus Zymomonas can spoil primed cask conditioned beer and cider. There is a wide range of Enterobacteraeceace which are found within brewery environments and they serve as indicator microorganisms for hygiene and sanitation. Gram negative strictly anaerobic bacteria such as Pectinatus and Megasphaera have recently emerged as a significant threat due to the improvement in reduction of oxygen levels in beer and an increase in production of unpasteurised beer. Pectinatus and Megasphaera are sensitive to routine cleaning agents used in breweries, but they can survive and proliferate in biofilms eventually causing spoilage of beer. This review focuses on Gram negative aerobic, facultative anaerobic and strictly anaerobic brewery related spoilage bacteria.

Epidemiological Characteristics, Resistance Patterns and Spread of Gram-Negative Bacteria Related to Colonization of Patients in Intensive Care Units

Our aim was to determine the epidemiological characteristics, the resistance patterns and the spread of Gram negative bacteria related to colonization of patients in adult Intensive Care Units. Methods: A prospective cohort of patients colonized and/or infected with Gram negative bacteria was conducted at two adult ICUs from hospitals in Brazil (April 2012 to February 2013). Nasal, groin and perineum swabs were performed. Samples were incubated on MacConkey and cetrimide agar (48 h at 37℃) and identification tests (Vitek-BioMérieux), antibiogram (Bauer-Kirby method), Carba NP test, Polymerase Chain Reaction (PCR) and sequencing were performed. The patterns of resistant microorganisms were compared by rep-PCR (Diversilab). Results: There were 53 cases of colonization. In these cases, we identified imipenem-resistant Acinetobacter baumannii (51%), Pseudomonas aeruginosa (32%), Klebsiella pneumoniae ESBL (38%) or imipenem resistant (5.6%). The use of antimicrobials and medical devices were related to colonization (p The resistance patterns expressed by Klebsiella pneumoniae were ESBL (CTX-M, SHV e TEM) and KPC2. A verified profile of Acinetobacter baumannii was related to OXA-23 and OXA-253 (OXA-143 variant). The profiles ESBL and KPC2 expressed by Klebsiella pneumoniae were distributed between the both ICUs. The distribution of OXA-23 and OXA-253 was verified only in one ICU. The similarity of strains ranged from 80% to 95%, highlighting the horizontal transference of these microorganisms.

The Five Years Surveillance and Trends of Antibiotic Resistance in Some Common Gram Negative Bacteria at the Vietnam Military Hospital

The study is to identify trends and levels of antibiotic resistance of some common Gram-negative strains over time. The samples were collected from Vietnam Military Hospital 103 between 2014 and 2019. A total of 405 Acinetobacter baumannii., 528 Pseudomonas aeruginosa, 741 Escherichia coli, and 352 Klebsiella pneumoniae strains were identified and antimicrobial susceptibility was by Vitek system and Etest method. The multi-drug resistance (MDR) was major proportion of four common bacteria. In particular, there is a tendency to shift from MDR to Extended drug resistance (XDR) or possibly Pan drug resistant (pPDR). A. baumannii had the highest level of antibiotic resistance, namely, carbapenem (61.5% - 82.5%) and cephalosporin (72.7% - 88.7%). P. aeruginosa resisted most of commonly antibiotics, ranging from 50% to 70%. E. coli had a high resistance with antibiotics like ampicillin (87.2% - 97.6%) and the 3rd generation cephalosporins (up to 79.6%). K. pneumoniae resisted carbapenem from 14.7% to 44.4%, and other antibiotics with the higher rate of 40%. The collected data will be a prerequisite for further studies on mechanisms and factors related to antibiotic resistant bacteria, in order to find out a rational and effective using strategy of antibiotics.

Prevalence and Antimicrobial Resistance of Gram-Negative Bacteria Isolates in Shellfish Samples from Two River Estuaries in South-South Nigeria

Antibiotic resistant bacteria pathogens remain the leading cause of shellfish borne diseases and a major health threat to humans worldwide. The objectives of this study were to isolate, identify, and determine the antibiotic resistance patterns of Gram-negative bacteria from shellfish. We analyzed a total of 540 shellfish (117 clams, 88 oysters, and 136 periwinkles) samples collected from different vendors at Iko and Douglas Creeks in Akwa Ibom State, South-South Nigeria. Conventional cultural techniques, morphological, biochemical characteristics, and PCR amplification were used to identify the bacterial isolates. Antibiotic susceptibility tests (Kirby-Bauer disk diffusion method) and ESBL phenotype (disk) of the isolates were performed. One hundred and thirty-five (135) Gram-negative bacteria comprising 5 genera and 14 species were detected at a prevalence of: Alcaligenes faecalis TRB-7 38 (28.2%), Pseudomonas oryzihabitans strain KCB005 16 (11.9%), Paenalcaligenes retgerii strain B5 12 (8.9%) Pseudomonas aeruginosa JB2 10 (7.4%), Providencia stuartii DMC-28b 9 (6.7%), Alcaligenes species TLT151 8 (5.9%), Pseudomonas aeruginosa CIFRI DTSB1 7 (5.2%), Paenalcaligenes species UN24 7 (5.2%), Alcaligenes faecalis BT10 7 (5.2%), Vibrio species strain PrVy108 6 (4.4%), Pseudomonas xiamenensis C10-2 5 (3.7%), Providencia vemicola Bu15_38 4 (2.9%), Pseudomonas anguillisceptica 4029 3 (2.2%), and Pseudomonas aeruginosa N15-01092 3 (2.2%). All tested isolates showed various degrees of resistance to the thirteen antimicrobials evaluated. High levels of resistance (100%) to cefepime and imipenem were expressed by all isolates except the Providencia species. For the EBSL indicators, all isolates apart from Alcaligenes species were resistant (100%) to ceftriaxone. All Vibrio species were susceptible to norfloxacin, nalidixic acid, and ceftazidime. The identification of antibiotic resistant Gram-negative bacteria (GNARB) from shellfish in this study highlights the risk of disseminated multi-drug resistance—a serious public health concern.

Prevalence and Antibiotic Resistance Patterns of Gram-Negative Uropathogens among Paediatric Patients in Nigeria

Objective: This study aimed to detect and compare the frequency and antibiotics resistant pattern of Gram-negative uropathogens implicated in urinary tract infections (UTIs) in paediatric patients attending some hospitals in Nigeria and to proffer recommendations for its management. Methods: Based on standard procedures, midstream urine samples were collected. Urinalysis was done as a preliminary diagnosis of UTI using Combi-9 test strip. Isolation of uropathogen was done and antibiotic sensitivity test was carried out using Kirby-Bauer technique. Results: Out of 489 samples collected, 130 (26.4%) was positive for UTI. The prevalence rate of UTI in the investigated areas such as Nsukka, Otukpo, Gboko and Kastina Ala was 31.8%, 17.5%, 34.3% and 17.1%, respectively. The prevalence of UTI was higher in males 81 (30.9%) than in females 49 (21.6%), but there was no statistically significant association between gender and UTI (p = 0.636). The prevalence of UTI was greater among the age of 2 - 5 years (28.2%) and decreased with the increase in age, although there was no significant association between UTI and the age groups (p = 0.870). Generally, Klebsiella pneumonae (88.8%) was the most dominant bacterium (it was even more in males), followed by E. coli (40.6%), which was more in females, then Pseudomonas spp. (45.0%) and Proteus mirabilis (13.8%). The in-vitro antibiotic susceptibility testing shows that the isolate was highly resistant to Augmentin, Cotrimoxazoel, Amoxicilin and Tetracycline, while some of the isolate shows intermediate resistant to Nitrofurantoin and Nalixidic acid. Ofloxacine and Gentamicin were the most effective antibiotics against the isolates from all the study areas. The isolates had a varied range of MICs and MBCs. Conclusion: K. pneumonia predominated all isolates. The resistant patterns of the isolates to some of the antibiotics show that the first line of antibiotics for treatment of UTI in children in these areas is Ofloxacine and Gentamicin.

The Increased Frequency of Carbapenem Resistant Non Fermenting Gram Negative Pathogens as Causes of Health Care Associated Infections in Adult Cancer Patients

Background and Aim: Multi drug resistant Non fermenting gram negative bacilli (NFGNB) have emerged as a major cause of health-care associated infections especially in immunocompromised hosts. The aim of the study was to investigate the prevalence of NFGNB as a cause of health-care associated infections (HAI) in cancer patients and determine their resistance pattern. Patients and Methods: During the study period, 158 NFGNB isolates were collected. Microscan Walk Away 9 was used for identification and testing for the metallo-β-lactamases (MBLs) was done by Imipenem-EDTA combined disk synergy test (CDST-IPM). Results: NFGNB represented 29.0% of infections caused by gram negative organisms. Carbapenem resistance, the multi-drug resistant (MDR) phenotype, and MBL production were documented in 70%, 63%, and 59% of NFGNB isolates, respectively. MDR-NFGNB rates were significantly higher among hospitalized patients, medical department and those with longer duration of hospital stay (p = 0.034, 0.026, 0.019;respectively) than non MDR-NFGNB. Conclusion: A high level of carbapenem and multi-drug resistance were detected among the non-fermenter pathogens isolated from hospitalized cases and were more frequently encountered in high risk adult cancer patients requiring longer duration of hospitalization. The MDR-NFGNB are constituting important causes of health-care associated infections in cancer patients.

Immunogenomics for identification of disease resistance genes in pigs: a review focusing on Gram-negative bacilli

Over the past years, infectious disease has caused enormous economic loss in pig industry. Among the pathogens, gram negative bacteria not only cause inflammation, but also cause different diseases and make the pigs more susceptible to virus infection. Vaccination, medication and elimination of sick pigs are major strategies of controlling disease. Genetic methods, such as selection of disease resistance in the pig, have not been widely used. Recently, the completion of the porcine whole genome sequencing has provided powerful tools to identify the genome regions that harboring genes controlling disease or immunity. Immunogenornics, which combines DNA variations, transcriptorne, immune response, and QTL mapping data to illustrate the interactions between pathogen and host immune system, will be an effective genomics tool for identification of disease resistance genes in pigs. These genes will be potential targets for disease resistance in breeding programs. This paper reviewed the progress of disease resistance study in the pig focusing on Gram-negative bacilli. Major porcine Gram-negative bacilli and diseases, suggested candidate genes/pathways against porcine Gram-negative bacilli, and distributions of QTLs for immune capacity on pig chromosomes were summarized. Some tools for immunogenomics research were described. We conclude that integration of sequencing, whole genome associations, functional genomics studies, and immune response information is necessary to illustrate molecular mechanisms and key genes in disease resistance.

Green Fluorescent Protein Recombinant Nisin as a Probe for Detection of Gram-Positive Bacteria

A great amount of foodborne pathogens were Gram-positive (G+) bacteria, a threat to public health. In this study, considering the binding ability of nisin towards G+ bacteria and the stable fluorescent ability of EGFP protein, a fluorescent nisin–EGFP protein probe was constructed by a gene engineering method. Nisin and EGFP were used as the receptor and fluorophore, respectively, to detect G+ bacteria. The nisin and egfp gene were amplified separately according to the sequence published in GenBank using unique primers. The two genes were cloned into a pET-28b(+) vector resulting in a pET-28b(+)–nisin–egfp vector. The vector was transferred into Escherichia coli (E. coli) BL21 (DE3) for expression. The expressed protein was extracted, purified by a Ni–NTA column, and then tested by the SDS-PAGE method to confirm its molecular weight. Listeria monocytogenes (L. monocytogenes), Staphylococcus aureus (S. aureus), and Micrococcus luteus (M. luteus) were used as the representations of G+ bacteria. E. coli O157, representing the gram-negative (G−) bacteria, was used as a negative control. The binding specificity of the recombinant protein was performed on two types of bacteria and then detected through fluorescent microscopy. The results indicated that the nisin–EGFP probe could detect G+ bacteria at 108CFU/mL. © 2017, Tianjin University and Springer-Verlag Berlin Heidelberg.

腹膜透析相关性腹膜炎的致病菌及药敏试验分析

目的回顾性分析该院腹膜透析相关性腹膜炎(PDAP)的病原菌谱特点及预后转归情况,为该院腹膜炎的防治提供科学依据。方法回顾性选取2017年1月至2023年2月该院收治的69例PDAP患者的临床资料,分析其发病原因、病原菌谱特点及预后转归情况。结果69例PDAP患者腹膜透析透出液共培养出病原菌43例,阳性率为62.32%,43例病原菌中革兰阳性菌23例(53.49%),革兰阴性菌17例(39.53%),真菌3例(6.98%)。43例病原菌感染原因包括肠道感染18例(41.86%),换液操作不规范11例(25.58%),呼吸道感染8例(18.60%),原因不明6例(13.95%)。革兰阳性菌以表皮葡萄球菌(10例)为主,革兰阴性菌以大肠埃希菌(7例)为主。革兰阳性菌对万古霉素、利奈唑胺、替加环素、替考拉宁、莫西沙星均敏感,对克林霉素(52.17%)、红霉素(56.52%)、阿莫西林/克拉维酸(60.87%)、青霉素G(78.26%)耐药;革兰阴性菌对美罗培南、亚胺培南、黏菌素均敏感,对阿莫西林/克拉维酸(47.06%)、头孢呋辛(47.06%)、头孢唑啉(52.94%)、氨苄西林(82.35%)耐药;真菌对氟康唑、伏立康唑、两性霉素B和卡泊芬净均敏感。69例PDAP患者共治愈53例,退出14例,死亡2例,治愈率为76.81%,真菌性PDAP患者退出率明显高于革兰阳性菌、革兰阴性菌及培养阴性的PDAP患者。结论该院腹膜透析患者发生PDAP的主要原因为换液操作不规范和肠道感染,PDAP相关致病菌以革兰阳性菌为主,真菌性PDAP患者退出率较高。

儿童重症肺炎支气管肺泡灌洗液的病原菌及药敏试验分析

目的了解儿童重症肺炎支气管肺泡灌洗液(BALF)的病原菌及药敏试验情况。方法选取该院2021年1月至2023年4月收治的100例重症肺炎患儿作为研究对象,对所有患儿进行支气管镜肺泡灌洗,并分析其BALF病原菌及药敏试验情况。结果100例患儿BALF中共培养出病原菌131株,革兰阴性菌98株(74.81%),革兰阳性球菌33株(25.19%),其中流感嗜血杆菌(25.19%)、肺炎链球菌(21.37%)占比较高,卡他布兰汉菌(15.27%)、肺炎克雷伯菌(11.45%)其次。重症肺炎患儿BALF中前4位病原菌主要以<1岁(97.37%)、1~3岁(96.88%)占比较高,>3~7岁(94.12%)、>7~14岁(92.31%)相对较少。各年龄BALF中流感嗜血杆菌、卡他布兰汉菌、肺炎克雷伯菌分布情况比较,差异均无统计学意义(P>0.05);各年龄BALF中肺炎链球菌分布情况比较,差异有统计学意义(P<0.05)。20株流感嗜血杆菌对四环素、阿莫西林-克拉维酸、头孢噻肟、复方磺胺甲噁唑均较敏感,对氯霉素敏感性其次,对氨苄西林、头孢克洛、头孢呋辛耐药性均较高;15株卡他布兰汉菌对头孢噻肟较敏感,对氨苄西林耐药性最高;8株肺炎克雷伯菌对头孢噻肟较敏感,对氨苄西林、头孢呋辛、氯霉素耐药性均较高,对阿莫西林-克拉维酸、四环素耐药性其次;20株肺炎链球菌对万古霉素、氯霉素均较敏感,对青霉素G、泰利霉素敏感性其次,对复方磺胺甲噁唑耐药性较高,对四环素、头孢噻肟、克林霉素耐药性其次。结论儿童重症肺炎BALF中病原菌以流感嗜血杆菌、肺炎链球菌多见,且0~3岁患儿病原菌占比高于>3~14岁,临床应合理用药以预防耐药菌株产生。

耐碳青霉烯类革兰阴性菌致泌尿系结石患者并发尿源性脓毒血症6例报告及文献复习

目的探讨泌尿系结石患者耐碳青霉烯类革兰阴性菌(CRGNB)感染致尿源性脓毒血症的临床特点与治疗策略。方法回顾性分析新疆医科大学第一附属医院收治的6例因CRGNB感染致尿源性脓毒血症的泌尿系结石患者的临床数据,结合近几年国内外治疗该疾病的指南和相关文献重点分析其临床感染特征和临床抗感染用药。结果6例患者均为院内获得性感染,具有输尿管支架管置入史及侵入性操作史,均进行细菌培养实验,并检出CRGNB共7株,采用单药或多药联合的治疗方案,经抗感染治疗均好转。其中病例3、4、6依据药敏试验最小抑制浓度(MIC)值选择用药,疗效良好。结论泌尿系结石患者CRGNB感染致尿源性脓毒血症多发于细菌培养阳性、侵入性操作患者,抗感染治疗有效,需根据患者具体情况和细菌耐药性变化灵活调整用药策略,以达到最佳治疗效果。

湖南省细菌耐药监测网2012-2021年ICU分离细菌耐药性监测报告

目的了解2012—2021年湖南省细菌耐药监测网网点医院重症监护病房(ICU)患者临床分离菌株分布情况及对抗菌药物的敏感性。方法按照全国细菌耐药监测网方案,应用WHONET 2022软件对所有湖南省耐药监测网成员单位上报的ICU临床分离细菌及药敏结果数据进行分析。结果2012—2021年各年份湖南省细菌耐药监测网成员单位ICU分离细菌总数为5777~22369株,其中革兰阴性菌每年占比为76.1%~78.0%。金黄色葡萄球菌一直稳居每年分离的革兰阳性菌之首。革兰阴性菌中,居前5位的细菌分别为鲍曼不动杆菌、肺炎克雷伯菌、大肠埃希菌、铜绿假单胞菌和嗜麦芽窄食单胞菌。耐甲氧西林金黄色葡萄球菌检出率呈逐年下降趋势,未发现对万古霉素、替考拉宁及利奈唑胺耐药的葡萄球菌属细菌。耐万古霉素粪肠球菌检出率为0.6~1.1%,耐万古霉素屎肠球菌检出率为0.6%~2.2%。大肠埃希菌、肺炎克雷伯菌对亚胺培南的耐药率分别为3.1%~5.7%、7.7%~20.9%。铜绿假单胞菌、鲍曼不动杆菌对亚胺培南耐药率分别为24.6%~40.1%、76.1%~80.9%,耐碳青霉烯类铜绿假单胞菌检出率呈逐年下降趋势,鲍曼不动杆菌对多黏菌素B保持了较高的敏感性,耐药率<10%。结论ICU临床分离菌对常见抗菌药物的耐药形势较严峻,尤其是耐碳青霉烯类肠杆菌目细菌在2019年后有升高趋势,需要加强细菌耐药监测,开展多学科联动。

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。

不同外源Cd(Ⅱ)对Pseudomonas aeruginosa EPS的胁迫效应--产量、组分、吸附特性变化及其机制

以CdCl_(2)、CdSO_(4)和Cd(NO_(3))_(2)为胁迫因子,比较了不同阴离子在胁迫/诱导过程中对Pseudomonas aeruginosa(P.aeruginosa)胞外聚合物(EPS)的产量和特性的影响以及对Cd(II)吸附性能的变化.研究发现,当Cd(NO_(3))_(2)胁迫/诱导浓度为50mg/L时,EPS产量达到214.91mg/g VSS,其中蛋白质含量达到136.75mg/g VSS,较胁迫/诱导前增加了409.31%.此时EPS的吸附性能最好,对Cd(II)的平衡吸附量最大,较胁迫/诱导前增加了近一半.HPLC分析表明,EPS蛋白质中氨基酸的变化与EPS的吸附特性密切相关.3D-EEM、XPS和FTIR结果表明,EPS中C=O、C-N和N-H含量增加,有利于重金属的结合.竞争吸附实验发现,EPS对Cd(II)的亲和力高于Zn(II).