Distribution of pathogenic bacteria and antimicrobial sensitivity of eye infections in Suzhou

AIM:To investigate the types of bacteria in patients with eye infections in Suzhou and their drug resistance to commonly used antibacterial drugs.METHODS:The clinical data of 155 patients were retrospectively collected in this study,and the pathogenic bacteria species and drug resistance of each pathogenic bacteria were analyzed.RESULTS:Among the 155 patients(age from 12 to 87 years old,with an average age of 57,99 males and 56 females)with eye infections(160 eyes:74 in the left eye,76 in the right eye and 5 in both eyes,all of which were exogenous),71(45.81%)strains were gram-positive bacteria,23(14.84%)strains were gram-negative bacteria and 61(39.35%)strains were fungi.Gram-positive bacteria were highly resistant to penicillin and erythromycin(78.87%and 46.48%respectively),but least resistant to vancomycin at 0.Gram-negative bacteria were highly resistant to cefoxitin and compound sulfamethoxazole(100%and 95.65%respectively),but least resistant to meropenem at 0.Comparison of the resistance of gram-positive and gram-negative bacteria to some drugs revealed statistically significant differences(P<0.05)in the resistance of both to cefoxitin,cotrimoxazole,levofloxacin,cefuroxime,ceftriaxone and ceftazidime,and both had higher rates of resistance to gram-negative bacteria than to gram-positive bacteria.The distribution of bacterial infection strains showed that Staphylococcus epidermidis was the most common strain in the conjunctiva,cornea,aqueous humor or vitreous body and other eye parts.Besides,Fusarium and Pseudomonas aeruginosa were also among the most common strains of conjunctival and corneal infections.CONCLUSION:Gram-positive bacteria are the dominant bacteria in eye infections,followed by gram-negative bacteria and fungi.Considering the resistance of gramnegative bacteria to multiple drugs,monitoring of bacteria should be strengthened in eye bacterial infections for effective prevention and control to reduce complications caused by eye infections.

Fluorescent antibiotics for real-time tracking of pathogenic bacteria

The harm of pathogenic bacteria to humans has promoted extensive research on physiological processes of pathogens,such as the mechanism of bacterial infection,antibiotic mode of action,and bacterial antimicrobial resistance.Most of these processes can be better investigated by timely tracking of fluorophore-derived antibiotics in living cells.In this paper,we will review the recent development of fluorescent antibiotics featuring the conjugation with various fluorophores,and focus on their applications in fluorescent imaging and real-time detection for various physiological processes of bacteria in vivo.

Synergistic Effect of Combined Antibiotics against Some Selected Multidrug Resistant Human Pathogenic Bacteria Isolated from Poultry Droppings in Akure, Nigeria

Antibiotic resistant bacteria pass between humans, between animals and between humans and animals in both directions, the use of antibiotics in poultry has contributed to multiple antibiotic resistant in pathogenic bacteria and use of two antibiotics might prevent the emergence of resistance to either. In this study, synergistic effect of combined antibiotics against multidrug resistant human pathogenic bacterial isolates from poultry droppings in Akure, Nigeria was examined. Collection of samples, isolation and identification of bacteria were carried out using standard microbiological method, antibiotic sensitivity test was performed by disc diffusion method and zone of inhibition was used to interpret the sensitivity test as resistant, susceptible or intermediate while combined effects of two antibiotics were investigated by macrobroth dilution and checkerboard assay methods while the synergetic effects of combined antibiotics were calculated using Fractional Inhibitory Concentration (FIC) and percentage synergistic interaction was calculated. All the ten (10) species of bacterial isolates were multidrug resistant and are less resistant to ofloxacin. The highest percentage synergistic interactions observed were Ofloxacin + Amoxicillin (90%), Ciprofloxacin + Amoxicillin (90%), Tetracycline + Amoxicillin (70%), Tetracycline + Augmentin (80%), Cotrimoxazol + Amoxicillin (50%), Cotrimoxazol + Augmentin (70%), Chloramphenicol + Amoxicillin (70%) and Chloramphenicol + Augmentin (80%). Poultry droppings is a potential source of human pathogenic bacteria, high frequency of multiple antibiotic resistance bacteria observed in this study is of great treat to man as this may cause the treatment of infection caused by these bacteria to be difficult. Combination of beta-lactam antibiotic with fluoroqunolones, tetracycline, Chloramphenicol and Cotrimoxazole was synergetic and this will reduce dose related toxicity and prevent resistance to single antibiotic.

Ocular bacterial infections at a tertiary eye center in China: a 5-year review of pathogen distribution and antibiotic sensitivity

AIM: To provide statistical evidence for the use of antibiotics in ophthalmology by assessing the distribution and antibiotic sensitivity of bacterial isolates from ocular specimens with suspected microbial infections.METHODS: This study applied a retrospective analysis of 3690 bacterial isolates from ocular specimens, which were obtained from the conjunctiva, cornea, aqueous humor, vitreous body, and other ocular sites of the patients at Shandong Eye Institute in northern China from January 2013 to December 2017. The parameters assessed mainly included the distribution of isolated bacteria and the results of susceptibility tests for antibiotics. In the analysis of antibiotic sensitivities, the bacteria were divided into four groups according to gram staining, and statistical methods were used to compare their antibiotic sensitivities. RESULTS: Among the 3690 isolated bacterial strains, Staphylococcus epidermidis(2007, 54.39%) accounted for the highest proportion. As for the total isolates, their sensitivity rate to gatifloxacin was up to 90.01%, with four types of gram-stained bacteria being all highly sensitive to it, but their sensitivity rate to levofloxacin was only 51.91%. The sensitivity rate of gram-negative bacilli(G-B) to levofloxacin was 83.66%, significantly higher than the other three types of gram-stained bacteria(P<0.05). Gram-positive cocci (G+C, 97.95%) and gram-positive bacilli(G+B, 97.54%) were more sensitive to vancomycin than gram-negative cocci(G-C, 70.59%) and G-B(68.57%;P<0.05). For fusidic acid, the sensitivity rates of G+C(89.83%) and G+B(73.37%) were significantly higher than that of G-B(29.83%;P<0.05). The gram-negative bacteria's sensitivity rate to cefuroxime was as low as 59.25%, but only G-B was less sensitive to cefuroxime(57.28%), while G-C was still highly sensitive(89.29%). The sensitivity rate of gram-positive bacteria to moxifloxacin was as high as 80.28%, but only G+C was highly sensitive to moxifloxacin(81.21%), while G+B was still less sensitive(32.00%). CONCLUSION: Staphylococcus epidermidis is the predominant isolate in all ocular specimens with bacteria. Gatifloxacin is more suitable for topical prophylactic use than levofloxacin in ophthalmology when necessar y. Vancomycin and fusidic acid both have better effects on gram-positive bacteria than gram-negative bacteria. More accurate antibiotic sensitivity analysis results can be obtained when a more detailed bacterial classification and more appropriate statistical methods are performed.

Occurrence and Antibiotic Sensitivity of Bacterial Strains Isolated from Nile Tilapia, <i>Oreochromis niloticus</i>Obtained in Ibadan, Southwest Nigeria

The bacteriological quality of both wild and cultured Nile Tilapia, Oreochromis niloticus, sourced in some area of Ibadan, Southwest, Nigeria was studied. Bacteria flora of the skin and stomach of fish samples were examined and compared statistically (t-test independent). The resistance of bacterial isolates to commonly used antibiotics was also studied. Total aerobic bacteria count [colony forming unit: CFU = 159.50.13 ± 72, t Enterobacteriaceae count [(CFU) = 74.08 ± 5.55] with significant difference in the stomach were obtained in the Nile tilapia. The bacteria in the genera Staphylococcus, Escherichia, Proteus, Bacillus, Klebsiella, Micrococcus, Serratia, Pseudomonas, Salmonella and Streptococcus were isolated and had been proven to be of great public health significance. About 87.5% of the tested isolates were resistant to augmentin, 83.33% to cotrimoxazole and nalidixic acid. In addition, 79.17% of the isolates were resistant to tetracycline, 75.0% to amoxicillin, 54.17% to nitrofuratoin, 50.00% to ofloxacin and 29.17% to gentamicin. Among the eight antibiotics tested, six patterns of drug resistance were obtained and all of them were multiple drug resistance with three to eight. The public health implications of these observations are discussed.

Quantification of multi-antibiotic resistant opportunistic pathogenic bacteria in bioaerosols in and around a pharmaceutical wastewater treatment plant

Pharmaceutical wastewater treatment plants（WWTPs） are thought to be a ＂seedbed＂ and reservoirs for multi-antibiotic resistant pathogenic bacteria which can be transmitted to the air environment through aeration. We quantified airborne multi-antibiotic resistance in a full-scale plant to treat antibiotics-producing wastewater by collecting bioaerosol samples from December2014 to July 2015. Gram-negative opportunistic pathogenic bacteria（GNOPB） were isolated, and antibiotic susceptibility tests against 18 commonly used antibiotics, including 11 β-lactam antibiotics, 3 aminoglycosides, 2 fluoroquinolones, 1 furan and 1 sulfonamide, were conducted.More than 45% of airborne bacteria isolated from the pharmaceutical WWTP were resistant to three or more antibiotics, and some opportunistic pathogenic strains were resistant to 16 antibiotics, whereas 45.3% and 50.3% of the strains isolated from residential community and municipal WWTP showed resistance to three or more antibiotics. The calculation of the multiple antibiotic resistance（MAR） index demonstrated that the air environment in the pharmaceutical WWTP was highly impacted by antibiotic resistance, while the residential community and municipal WWTP was less impacted by antibiotic resistance. In addition, we determined that the dominant genera of opportunistic pathogenic bacteria isolated from all bioaerosol samples were Acinetobacter, Alcaligenes, Citrobacter, Enterobacter, Escherichia, Klebsiella, Pantoea, Pseudomonas and Sphingomonas. Collectively, these results indicate the proliferations and spread of antibiotic resistance through bioaerosols in WWTP treating cephalosporin-producing wastewater, which imposed a potential health risk for the staff and residents in the neighborhood, calling for administrative measures to minimize the air-transmission hazard.

Occurrence of human pathogenic bacteria carrying antibiotic resistance genes revealed by metagenomic approach: A case study from an aquatic environment

Antibiotic resistance genes(ARGs), human pathogenic bacteria(HPB), and HPB carrying ARGs are public issues that pose a high risk to aquatic environments and public health. Their diversity and abundance in water, intestine, and sediments of shrimp culture pond were investigated using metagenomic approach. A total of 19 classes of ARGs, 52 HPB species, and 7 species of HPB carrying ARGs were found. Additionally, 157, 104, and 86 subtypes of ARGs were detected in shrimp intestine, pond water, and sediment samples, respectively. In all the samples, multidrug resistance genes were the highest abundant class of ARGs. The dominant HPB was Enterococcus faecalis in shrimp intestine, Vibrio parahaemolyticus in sediments, and Mycobacterium yongonense in water, respectively. Moreover, E. faecalis(contig Intestine_364647)and Enterococcus faecium(contig Intestine_80272) carrying efr A, efr B and ANT(6)-Ia were found in shrimp intestine, Desulfosaricina cetonica(contig Sediment_825143) and Escherichia coli(contig Sediment_188430) carrying mex B and APH(3′)-IIa were found in sediments, and Laribacter hongkongensis(contig Water_478168 and Water_369477), Shigella sonnei(contig Water_880246),and Acinetobacter baumannii(contig Water_525520) carrying sul1, sul2, ere A, qac H, OXA-21, and mph D were found in pond water. Mobile genetic elements(MGEs) analysis indicated that horizontal gene transfer(HGT) of integrons, insertion sequences, and plasmids existed in shrimp intestine, sediment, and water samples, and the abundance of integrons was higher than that of other two MGEs. The results suggested that HPB carrying ARGs potentially existed in aquatic environments, and that these contributed to the environment and public health risk evaluation.

Antibiotic sensitivity pattern of bacterial pathogens in the intensive care unit of Fatmawati Hospital,Indonesia

Objective:To evaluate the sensitivity pattern of bacterial pathogens in the intensive care unit(ICU) of a tertiary care of Falmawati Hospital Jakarta Indonesia.Methods:A cross sectional retrospective study of bacterial pathogen was carried out on a total of 722 patients that were admitted to the ICU of Fatmawati Hospital Jakarta Indonesia during January 2009 to March 2010. All bacteria were identified by standard microbiologic methods,and(heir antibiotic susceptibility testing was performed using disk diffusion method.Results:Specimens were collected from 385 patients who were given antimicrobial treatment,of which 249(64.68%) were cultured positive and 136(35.32%) were negative.The most predominant isolate was Pseudomonas aeruginosa(P.aeruginosa)(26.5%) followed by Klebsiella pneumoniae(K.pneumoniae)(15.3%) and Staphylococcus epidermidis(14.9%).P.aeruginosa isolates showed high rate of resistance to cephalexin(95.3%),cefotaxime(64.1%),and ceftriaxone(60.9%).Amikacin was the most effective(84.4%) antibiotic against P.aeruginosa followed by imipenem(81.2%),and meropenem(75.0%).K.pneumoniae showed resistance to cephalexin(86.5%),ceftriaxone(75.7%),ceftazidime(73.0%),cefpirome(73.0%) and cefotaxime(67.9%),respectively.Conclusions:Most bacteria isolated from ICU of Fatmawati Hospital Jakarta Indonesia were resistant to the third generation of cephalosporins,and quinolone antibiotics.Regular surveillance of antibiotic susceptibility pallerns is very important for setting orders to guide the clinician in choosing empirical or directed therapy of infected patients.

Isolation and Identification of Houttuynia cordata Endophytic Bacteria and Study of Antibiotic Activity

[Objectives]To further explore the resources of biocontrol strains and provide new options for the control of pathogenic bacteria.[Methods]Houttuynia cordata endophytic bacteria were isolated and identified,and the antibiotic activity was explored.[Results]There are 8 strains(H1-H8)of endophytic bacteria isolated from the healthy plants of H.cordata,which had an antagonistic effect on the pathogenic bacteria.According to the gene sequence,the 8 strains were identified as Stenotrophomonas,Pseudomonas,and Bacillus,which strongly inhibited Colletotrichum(HC1),Fusarium(HC2),and Rhizoctonia(HC5)of H.cordata.On the PDA culture dish,the inhibition diameter of the 8 strains on Colletotrichum,Fusarium,and Rhizoctonia was 6,8,and 5 mm,respectively.[Conclusions]Pathogenic bacteria and endophytic bacteria inoculated with H.cordata seedlings showed that endophytic bacteria have certain antagonistic activity,and have the potential for development and application.

Identification of Pathogenic Germs and Antibiotics Residues in the Raw Milk and Their Effects on Human Health

Milk is a food of great value, it provides more essential nutrient than any other natural food. The presence of pathogenic bacteria and antibiotic residues in milk can cause a real danger to consumers. Effectively, the milk consumption contaminated by bacteria can have an immediate impact which means a toxi-infection. Therefore, the presence of antibiotics residues in milk can constitute an important risk at the allergic and antibiotic resistance cases on the consumer. The present study concerning the pathogens germs identification and Antibiotic residues seeking in milk and their impact on the human health, has been realized on a total number of 80 samples of raw milk resulted from direct sale channel （dairies） throughout Blida different regions localities. The Microbiological analysis has shown only three conform samples to JORA Standards. Really, milk non-conformity results to the microbiological standards consisting on total aerobic mesophilic flora total count, total coliforms, Thermotolerant coliforms E. coli, Faecal streptococcus, Staphylococcus aureus have shown the following contamination rate： 61.25%, 93.75%, 86.25%, 55%, 93.75% and 50%. Salmonella is characterized by a total absence in all analyzed milk samples. Moreover, the antibiotics residues research by Delvotest SP make plainly visible 33 positive samples. Further, two samples of the three which were judged conform to the bacteriology standards has been found contaminated by the antibiotic residues. The analyzed milk quality can be considered as a real danger to the consumption.

A preliminary study of the relationship between antibiotic administration and changes in bacteriological profile of wound infection in a burn unit

To investigate the relationship between antibiotic administration and the changes in bacteriological profile in a burn unit. Methods: The data of consumption of different kinds of antibiotics, including total antibiotic consumption [expressed as the number of defined daily doses (DDD)] as well as pathogen identification, werecollected in a 8-year period. The constituent ratios of different kinds of antibiotics in total antibiotic consumption toisolation rates of various species of bacteria were calculat...

Occurrence and Evaluation of Chromium Reducing Bacteria in Seepage Water from Chromite Mine Quarries of Orissa, India

Chromium pollution due to leaching and weathering of chromite mine overburden in mine seepage water is a serious environmental problem. In an attempt to explore the indigenous chromate resistant and reducing bacteria from chromite mine quarry seepage, 145 aerobic, heterotrophic bacteria were isolated from 14 mine seepage samples derived from chromite mines of Sukinda valley and Baula-Nuasahi belt in Orissa, India. A total of 109 isolates which were tolerant to 2 mM Cr(VI) showed different degrees of Cr(VI) reducing activ-ity in complex KSC medium and synthetic Vogel Bonner (VB) broth. Ten isolates belonging to genera like Pseudomonas, Acinetobacter, Alcaligenes, Cupriavidus and Corynebacterium were selected on the basis of their chromate reducing efficiency and it was found that they could reduce more than 50 and 75% of Cr(VI) in VB broth and KSC medium respectively. The sole Gram-positive isolate, Corynebacterium paurometabo-lum SKPD 1204 (MTCC 8730) showed maximum chromate reducing capacity in both VB broth (63.7%) and KSC medium (92%) and was capable of reducing nearly 95% of the total Cr(VI) in the mine seepage when it was grown in the mine seepage supplemented with 2% VB concentrate.

COVID-19 Coronavirus: Is Infection along with <i>Mycoplasma</i>or Other Bacteria Linked to Progression to a Lethal Outcome?

Most patients with COVID-19 disease caused by the SARS-CoV-2 virus recover from this infection, but a significant fraction progress to a fatal outcome. As with some other RNA viruses, co-infection or activation of latent bacterial infections along with pre-existing health conditions in COVID-19 disease may be important in determining a fatal disease course. Mycoplasma spp. (M. pneumonaie, M. fermentans, etc.) have been routinely found as co-infections in a wide number of clinical conditions, and in some cases this has progressed to a fatal disease. Although preliminary, Mycoplasma pneumoniae has been identified in COVID-19 disease, and the severity of some signs and symptoms in progressive COVID-19 patients could be due, in part, to Mycoplasma or other bacterial infections. Moreover, the presence of pathogenic Mycoplasma species or other pathogenic bacteria in COVID-19 disease may confer a perfect storm of cytokine and hemodynamic dysfunction, autoimmune activation, mitochondrial dysfunction and other complications that together cannot be easily corrected in patients with pre-existing health conditions. The positive responses of only some COVID-19 patients to antibiotic and anti-malaria therapy could have been the result of suppression of Mycoplasma species and other bacterial co-infections in subsets of patients. Thus it may be useful to use molecular tests to determine the presence of pathogenic Mycoplasma species and other pathogenic bacteria that are commonly found in atypical pneumonia in all hospitalized COVID-19 patients, and when positive results are obtained, these patients should treated accordingly in order to improve clinical responses and patient outcomes.

某三甲医院尿路感染患者病原菌分布及药敏分析

目的了解自贡市第三人民医院尿路感染患者病原菌分布及药敏耐药性特点,为临床医师合理选用抗菌素及控制院内感染、降低细菌耐药性提供帮助。方法收集2019年1月—2020年12月自贡市第三人民医院尿路感染就诊患者尿液标本3802份,采用MicroScan Walk/Away-40(美国SIEMENS公司)全自动微生物鉴定和药敏系统进行细菌鉴定和药敏试验。结果539株分离菌中革兰阴性菌411株,占比76.25%;革兰阳性菌128株,占比23.75%;其中前5位的菌株416株,依次为大肠埃希菌294株(54.55%)、粪肠球菌46株(8.53%)、肺炎克雷伯菌38株(7.05%)、屎肠球菌23株(4.27%)、奇异变形杆菌15株(2.78%)。前5位3种革兰阴性菌中,大肠埃希菌对复方新诺明、环丙沙星、头孢唑啉及左旋氧氟沙星耐药率均>50.00%,对头孢噻肟、头孢曲松、氨曲南和头孢吡肟耐药率均>40.00%,庆大霉素为35.71%,其余均在30.00%以内;肺炎克雷伯菌对复方新诺明耐药性最高为52.63%,其次是头孢唑林为42.11%、头孢噻肟为36.84%、环丙沙星和头孢曲松均为31.58%,其余均在30.00%以内;奇异变形杆菌,对复方新诺明耐药率最高为60.00%,其次环丙沙星为53.33%、妥布霉素为46.67%,头孢唑啉、庆大霉素和氨曲南均为33.33%,其余均在30.00%以内。前5位2种革兰阳性菌中,粪肠球菌,对四环素耐药性最高为86.96%,其次红霉素为76.09%、利福平为54.35%,环丙沙星为32.61%、左旋氧氟沙星和莫西沙星均为30.43%,其余均在30.00%以内;屎肠球菌,对红霉素、环丙沙星和左旋氧氟沙星耐药率均为100%,其次青霉素G为95.65%、莫西沙星为91.30%、利福平和阿莫西林/克拉维酸均为82.61%、四环素为65.22%,对大多数抗菌药物耐药率均较高,其中对万古霉素耐药率最低为4.35%,其次为利奈唑胺为5.26%、呋喃妥因为8.70%。结论临床医师在诊疗过程中,应加强与实验室合作,重视尿路感染的病原学检查,在选用抗菌药物治疗时应结合实验室病原学报告和药敏试验结果,合理使用抗菌药物,同时遏制细菌耐药性。

血液病房产超广谱β-内酰胺酶菌分布情况及药物敏感性分析

目的分析2020年1月至2021年11月江西省九江市第一人民医院(以下简称“本院”)血液病房产超广谱β-内酰胺酶(ESBLs)菌分布情况及药物敏感性。方法选取2020年1月至2021年11月江西省九江市第一人民医院血液病房138例患者作为研究对象,收集患者的分泌物进行病原菌培养,并对产ESBLs菌分布情况和药物敏感性进行分析。结果革兰氏阴性菌居多,共分离出160株,占比80.00%,其次是真菌和革兰氏阳性菌,各分离出22株和18株。其中以铜绿假单胞菌、大肠埃希菌和肺炎克雷伯菌最为常见。本院血液病房病原菌共检出200株,检出情况主要以痰、中段尿、咽拭子居多,以肛拭子、大便检出较少;200株病原菌共检出产ESBLs菌56株,占比28.00%,以中段尿、咽拭子检出居多,脓液、肛拭子、大便中未检出。本院血液病房产ESBLs菌除对亚胺培南、美罗培南耐药率较低外,对大部分抗菌药物的耐药率均较高。结论本院血液病原菌以革兰氏阴性菌为主,且对抗菌药物的耐药率较高,临床应重点关注此类菌株感染,需引起重视,加强院感的防控,避免发生耐药菌的暴发和流行。

糖尿病足合并类鼻疽伯克霍尔德菌感染64例临床特征、药敏特点和治疗分析

目的 总结糖尿病足(DF)合并类鼻疽伯克霍尔德菌(BP)感染的临床特征、药敏特点和治疗方法。方法 回顾分析2012年1月至2022年3月海南医学院第二附属医院收治的64例DF合并BP感染病人的临床表现、微生物抗菌药物敏感性及治疗手段。结果 64例DF合并BP感染病人中,60例有发热症状、34例有白细胞升高、均有C反应蛋白(CRP)和降钙素原(PCT)升高、14例合并肝或脾脓肿、30例出现肝功能不全、20例出现肾功能不全、18例合并感染性休克。64株BP对大多数常见的抗生素敏感性较差,但均对亚胺培南、美罗培南和复方磺胺甲唑敏感。所有病人均使用胰岛素积极控制血糖,大多数静脉应用碳青霉素烯类抗菌素约6周,出院后继续使用复方磺胺甲唑治疗。最终22例治愈,30例好转,8例未愈,4例死亡。死亡病例均合并多器官功能障碍。结论 DF合并BP主要表现为发热、CRP和PCT明显升高、合并肝或脾脓肿和肝肾功能不全,易出现感染性休克。对高度怀疑BP感染病人应多次进行培养,并及早静脉应用碳青霉素烯类抗菌素可能有助于改善预后。

太仓地区糖尿病足部感染患者病原菌分布及药敏和耐药性分析

目的探究太仓地区糖尿病足部感染患者病原菌分布及药敏和耐药情况。方法将70例糖尿病足部感染分泌物阳性患者纳入本次研究中,收取时间段在2013年8月至2022年3月,对患者病原菌分布、药敏、耐药性进行分析。结果70例患者中,一共检出26种类细菌,均为革兰阳性菌感染33例(共计41株),占比47.14%;均为革兰阴性菌感染26例(共29株),占比37.14%;阳性菌与阴性菌混合感染11例(共计22株),占比15.71%。在均是革兰阳性菌感染中以金黄色葡萄球菌、无乳链球菌最常见,药敏提示它们对万古霉素、利奈唑胺、利福平、莫西沙星敏感性高,对青霉素、红霉素、克林霉素、苯唑西林耐药;均为革兰阴性菌感染的菌株较多,大肠埃希菌、肺炎克雷伯杆菌、奇异变形杆菌较多见,药敏提示对亚胺培南、氨曲南、环丙沙星、哌拉西林他唑巴坦、头孢哌酮钠舒巴坦敏感性高,少部分对头孢曲松、头孢呋辛耐药。阳性菌与阴性菌混合感染中,药敏提示它们对万古霉素、利奈唑胺、美罗培南、利福平、莫西沙星、哌拉西林舒巴坦敏感,对青霉素、红霉素、克林霉素、头孢呋辛、头孢曲松、头孢他啶、氨苄西林、环丙沙星、磺胺甲噁唑耐药,耐药率明显上升。结论太仓地区糖尿病足感染的致病菌分布广泛,经验性选择抗生素利于控制感染,病原学检测和药敏实验可为抗感染治疗提供精准依据。

1株山鸡源致病性大肠杆菌的分离鉴定

为查明秦皇岛市某山鸡养殖场山鸡大批量死亡病因,试验对分离到的致病优势菌株进行生化鉴定和16S rRNA基因序列分析,并测试分离菌对21种抗生素的敏感性,进一步采用PCR方法检测分离菌的耐药基因。利用清洁级昆明小鼠和SPF鸡胚分别对分离菌进行致病性试验,并采用PCR方法检测分离菌的毒力基因。结果显示:分离菌为革兰氏阴性杆菌,在伊红美蓝培养基上生长出有金属光泽的菌落,生化特性与大肠杆菌生化特性符合率高达99%。BLAST分析发现,分离菌16S rRNA序列与大肠杆菌的基因相似性高达99.8%。分离菌对恩诺沙星和阿米卡星高度敏感,对青霉素、头孢曲松等15种药物耐药。分离菌的磺胺类、β-内酰胺类、四环素类的耐药基因与耐药表型基本相符,其余耐药基因与耐药表型不符,提示该分离菌可能存在其他的耐药机制。致病性试验结果显示,分离菌具有较强致病性,共检测到12种大肠杆菌主要毒力基因。研究表明,分离菌为山鸡源致病性大肠杆菌,且耐药情况复杂,具有较强的毒力和致病性。

76例急性化脓性中耳炎患儿耳分泌物的病原菌分布情况及药敏结果分析

目的探究急性化脓性中耳炎患儿耳分泌物的病原菌分布情况及药敏结果。方法选取2018年1月—2023年5月武汉儿童医院接诊的76例急性化脓性中耳炎患儿,采集中耳分泌物行病原学培养及药敏试验检测,分析致病菌分布特征及药敏结果,并分析主要感染菌种的耐药性变迁结局。结果76例患儿共检出病原菌84株,肺炎链球菌和金黄色葡萄球菌的占比较高,分别为71.43%和23.81%。1个月~1岁、>1~3岁、>3~8岁患儿肺炎链球菌感染率分别为40.00%、35.00%和25.00%,金黄色葡萄球菌感染率分别为25.00%、30.00%和45.00%。肺炎链球菌对左旋氧氟沙星的耐药性2018~2019年低于2022~2023年(P<0.05)。肺炎链球菌对阿奇霉素、四环素和克林霉素的耐药性较高,分别为81.67%(49/60)、90.00%(54/60)和66.67%(40/60);对万古霉素和利奈唑胺的敏感性最高,耐药率均为0.00%;对氯霉素、厄他培南和奎奴普丁/达福普汀的耐药性较低,分别为8.33%(5/60)、13.33%(8/60)和10.00%(6/60);对左旋氧氟沙星、美罗培南、复方新诺明、头孢噻肟、头孢曲松、头孢吡肟和青霉素均存在不同程度的耐药性,耐药率为21.67%~48.33%。金黄色葡萄球菌对左旋氧氟沙星、头孢吡肟、阿奇霉素、四环素和克林霉素的耐药性较高,分别为70.00%(14/20)、65.00%(13/20)、65.00%(13/20)、90.00%(18/20)和70.00%(14/20);对万古霉素、利奈唑胺的敏感性最高,耐药率均为0.00%;对氯霉素和奎奴普丁/达福普汀的耐药性较低,均为5.00%(1/20);对美罗培南、复方新诺明、头孢噻肟、头孢曲松、青霉素和厄他培南均存在不同程度的耐药性,耐药率为20.00%~50.00%。结论急性化脓性中耳炎患儿的病原菌分布中以肺炎链球菌和金黄色葡萄球菌占比最高,药敏试验得出两者对阿奇霉素、四环素及克林霉素的耐药性偏高,而对氯霉素、万古霉素、利奈唑胺、厄他培南及奎奴普丁/达福普汀的耐药性相对较低。

漂白粉消毒后对虾养殖源水细菌群落的响应特征研究

漂白粉消毒是凡纳滨对虾养殖源水常见的管控措施,可有效控制病原菌传播;然而,消毒会强烈扰动水体微生物群落,但源水细菌群落对漂白粉消毒的响应特征尚未阐明。在室内条件下,设置高浓度(60 mg/L)和低浓度(20 mg/L)漂白粉消毒源水,通过高通量测序及荧光定量PCR技术探究消毒后源水细菌群落、病原菌及抗生素抗性基因(ARGs)的动态响应规律。结果显示,消毒后,拟杆菌门(Bacteroidota)丰度上升,高浓度组变形菌门(Proteobacteria)的丰度显著降低;至第3天,两组源水的细菌群落组成趋于一致。此外,漂白粉消毒显著改变了源水的细菌群落结构及共现网络的复杂性。在控制水体病原菌方面,消毒后病原菌的总丰度降低,但种类增加,高浓度漂白粉消毒对病原菌的抑制作用更加显著。漂白粉消毒对ARGs的去除具有选择性,仅对sul1、floR、cfr、tetQ有一定的去除作用,且高、低浓度对ARGs的去除无差异。综上,60 mg/L可以作为漂白粉消毒养殖源水的更好浓度选择。研究结果从微生物生态视角评价了不同浓度漂白粉的消毒作用,可为对虾养殖生产中的源水管控提供理论支撑。