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Acinetobacter baumannii es una bacteria oportunista que representa un desafío significativo en el ámbito clínico debido a su rápida diseminación, elevada mortalidad y altos niveles de resistencia a los antimicrobianos convencionales. Esto ha impulsado la búsqueda de alternativas terapéuticas eficaces para el manejo de infecciones causadas por este patógeno. Objetivo: Evaluar la actividad antibacteriana in vitro del extracto de Taraxacum officinale (diente de león) frente a cepas de Acinetobacter baumannii. Materiales y Métodos: Se utilizaron cultivos in vitro con medio Muller Hinton y agar nutritivo para la activación y propagación de la cepa de referencia A. baumannii ATCC BAA-1605. Se obtuvo un extracto etanólico de T. officinale y se evaluaron diferentes concentraciones del mismo. Resultados: El extracto de T. officinale no mostró actividad antibacteriana significativa frente a. baumannii, ya que no se observó la formación de halos de inhibición, incluyendo en la prueba con el control positivo de Ciprofloxacina. Estos hallazgos llevaron a aceptar la hipótesis nula y rechazar la hipótesis alternativa, lo que sugiere una escasa eficacia del extracto de la planta frente a esta bacteria. Conclusiones: Se resalta la necesidad de realizar investigaciones más exhaustivas para comprender mejor los mecanismos de acción y la eficacia del extracto de T. officinale, así como explorar su potencial aplicación clínica en el tratamiento de infecciones causadas por A. baumannii dado que esta bacteria presenta altos niveles de resistencia a los antimicrobianos convencionales
Acinetobacter baumannii is an opportunistic bacteria that represents a significant challenge in the clinical field due to its rapid dissemination, high mortality, and high levels of resistance to conventional antimicrobials. This has driven the search for effective therapeutic alternatives for the management of infections caused by this pathogen. Objective: To evaluate the in vitro antibacterial activity of the Taraxacum officinale (dandelion) extract against Acinetobacter baumannii strains. Materials and Methods: In vitro cultures with Muller Hinton medium and nutrient agar were used for the activation and propagation of the reference strain A. baumannii ATCC BAA-1605. An ethanolic extract of T. officinale was obtained, and different concentrations of the extract were evaluated. Results: The T. officinale extract did not show significant antibacterial activity against A. baumannii, as no formation of inhibition halos was observed, including in the test with the positive control of Ciprofloxacin. These findings led to accepting the null hypothesis and rejecting the alternative hypothesis, suggesting a poor efficacy of the plant extract against this bacterium. Conclusions: The need to conduct more extensive research to better understand the mechanisms of action and the efficacy of the T. officinale extract is highlighted, as well as to explore its potential clinical application in the treatment of infections caused by A. baumannii, as this bacterium presents high levels of resistance to conventional antimicrobials.
Acinetobacter baumannii é uma bactéria oportunista que representa um desafio significativo no campo clínico devido à sua rápida disseminação, elevada mortalidade e altos níveis de resistência a antimicrobianos convencionais. Isso tem impulsionado a busca por alternativas terapêuticas eficazes para o manejo de infecções causadas por esse patógeno. Objetivo: Avaliar a atividade antibacteriana in vitro do extrato de Taraxacum officinale (dente-de-leão) contra cepas de Acinetobacter baumannii. Materiais e Métodos: Culturas in vitro com meio Muller Hinton e ágar nutritivo foram utilizadas para a ativação e propagação da cepa de referência A. baumannii ATCC BAA-1605. Um extrato etanólico de T. officinale foi obtido e diferentes concentrações do extrato foram avaliadas. Resultados: O extrato de T. officinale não mostrou atividade antibacteriana significativa contra A. baumannii, uma vez que não foi observada a formação de halos de inibição, incluindo no teste com o controle positivo de Ciprofloxacina. Esses achados levaram à aceitação da hipótese nula e rejeição da hipótese alternativa, sugerindo uma eficácia limitada do extrato da planta contra essa bactéria. Conclusões: Destaca-se a necessidade de realizar pesquisas mais amplas para compreender melhor os mecanismos de ação e a eficácia do extrato de T. officinale, bem como explorar sua potencial aplicação clínica no tratamento de infecções causadas por A. baumannii, uma vez que essa bactéria apresenta altos níveis de resistência a antimicrobianos convencionais.
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Abstract Background The COVID-19 pandemic has triggered crises in the public health sector that have complex and multifaceted interrelationships with antimicrobial resistance. It is important to evaluate the impact of COVID-19 on microbiological profile, antibiotic and alcohol gel consumption in Intensive Care Units (ICU). Methods This is a retrospective study undertaken in an infectious disease hospital located in Bahia/Brazil during three periods: from March 2019 to February 2020; from March 2020 to February 2021; and from March 2021 to February 2022. It was evaluated the incidence density of Candida spp and of multidrug-resistant Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species (ESKAPE group) in blood, urine and tracheal secretion isolated 48 h after the patient's admission to the ICU, as well as the use of alcohol gel (in milliliters) and consumption of antibiotics in Defined Daily Dose (DDD) per 1,000 ICU patient-days in the previous year and in the first two years of COVID-19 pandemic. Results There was an increase in Candida spp. (5.81, p < 0.001, IRR = 10.47, 95 % CI 2.57‒42.62) and in carbapenem-resistant A. baumannii in clinical cultures (4.71, p < 0.001, IRR = 8.46, 95 % CI 2.07‒34.60), the latter mainly in tracheal secretions (3.18, p =0.02, IRR = 11.47, 95 % CI 1.58‒83.39). A rise in the consumption of ceftriaxone and piperacillin-tazobactam, along with an increase in the utilization of alcohol gel were observed. Conclusion The shifting microbiological profile can be attributed to both the unique characteristics of patients with COVID-19 and the adjustments made to healthcare facilities' structural and work routines. Understanding these changes is essential in addressing the accelerated impact of antimicrobial resistance during the pandemic. Therefore, conducting thorough reviews of institutional practices and routines becomes critical in mitigating the consequences of antimicrobial resistance and its implications for patient care.
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Abstract Objectives This review highlights the existence and association of Acinetobacter baumannii with the oro-dental diseases, transforming this systemic pathogen into an oral pathogen. The review also hypothesizes possible reasons for the categorization of this pathogen as code blue due to its stealthy entry into the oral cavity. Methodology Study data were retrieved from various search engines reporting specifically on the association of A. baumannii in dental diseases and tray set-ups. Articles were also examined regarding obtained outcomes on A. baumannii biofilm formation, iron acquisitions, magnitude of antimicrobial resistance, and its role in the oral cancers. Results A. baumannii is associated with the oro-dental diseases and various virulence factors attribute for the establishment and progression of oro-mucosal infections. Its presence in the oral cavity is frequent in oral microbiomes, conditions of impaired host immunity, age related illnesses, and hospitalized individuals. Many sources also contribute for its prevalence in the dental health care environment and the presence of drug resistant traits is also observed. Its association with oral cancers and oral squamous cell carcinoma is also evident. Conclusions The review calls for awareness on the emergence of A. baumannii in dental clinics and for the need for educational programs to monitor and control the sudden outbreaks of such virulent and resistant traits in the dental health care settings.
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Objective @#To use linear PCR fragment containing antibiotic resistance cassette to carry out homologous recombination and replacement of target gene fragment of Acinetobacter baumannii to achieve rapid gene knockout and functional verification.@*Methods@#Acinetobacter baumannii Ab4294 was used as the research object,and the upper (901 bp) and lower ( 1 028 bp) reaches of fim gene cluster (4 980 bp in length) were amplified by PCR , which was used as the recombinant homologous arm.Kanamycin antibiotic resistance cassette (KanR) was ampli- fied from pUC57 plasmid.The above three fragments were connected by overlapping extended PCR technique,and the connected fragments were transformed into wild Acinetobacter baumannii strains.The gene deletion mutant was screened,and the plasmid complement strain was constructed.The phenotype of the obtained strains was identi- fied,and the function of fim gene cluster was explored. @*Results @#A mutant strain of Acinetobacter baumannii Ab4294 with deletion of fim gene cluster was successfully constructed by homologous substitution of linear PCR frag- ment containing antibiotic resistance cassette.Compared with the wild strain,the growth curve of the deletion strain had no significant difference ,and the rubbing ability significantly decreased ,and the phenotype recovered after complementing the gene cluster.@*Conclusion @#The fim family genes of Acinetobacter baumannii Ab4294 is success- fully knocked out by homologous substitution of linear PCR fragment containing antibiotic resistance cassette,which encodes the product involved in the motile movement of Acinetobacter baumannii.
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ObjectiveTo investigate a suspected outbreak of carbapenem-resistant Acinetobacter baumannii (CRAB) nosocomial infection in an intensive care unit (ICU) and provide scientific evidence for prevention and control of multi-drug resistant nosocomial infection. MethodsClinical and epidemiological data of 4 patients with CRAB infection were retrospectively investigated in the ICU of Renji Hospital in November 2021. Environmental hygiene monitoring and multilocus sequence typing (MLST) were conducted and intervention measures were taken. ResultsA total of 4 cases with CRAB infection were identified, among which 1 case was determined to be community-acquired and3 cases were hospital-acquired. The isolated strains shared the same drug resistance, and were all classified into ST368 type. In the surface and hand samples (n=40), 2 CRAB strains were detected in the air filter beside the bed of the first case, with a detection rate of 5%. After adopting comprehensive prevention and control strategies, including environmental cleaning and disinfection, hand hygiene, staff management and training, and supervision, no similar case with CRAB infection was found. ConclusionThis suspected outbreak of CRAB nosocomial infection may be induced by inadequate environmental cleaning and disinfection, and inadequate implementation of hand hygiene. Timely identification, investigation, and targeted measures remain crucial to effective control of possible nosocomial infection.
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<b>Objective</b> To evaluate the effectiveness of multi-disciplinary team (MDT) mode in the prevention and control of multidrug resistant organism (MDRO) infection in lung transplant recipients. <b>Methods</b> Lung transplant recipients admitted to the hospital from 2019 to 2022 were enrolled. MDT expert group was established in January, 2020. A series of prevention and control measures were conducted. The implementation rate of MDRO prevention and control measures and the detection rate of MDRO on the environmental surface from 2020 to 2022, and the detection rate of MDRO in lung transplant recipients from 2019 to 2022 were analyzed. <b>Results</b> The overall implementation rate of MDRO prevention and control measures for medical staff was increased from 64.9% in 2020 to 91.6% in 2022, showing an increasing trend year by year (<i>P</i><0.05). The detection rate of MDRO on the environmental surface was decreased from 28% in 2020 to 9% in 2022, showing a downward trend year by year (<i>P</i><0.05). The detection rate of MDRO in lung transplant recipients was decreased from 66.7% in 2019 to 44.3% in 2022, showing a decreasing trend year by year (<i>P</i><0.001). <b>Conclusions</b> MDT mode management may enhance the implementation of MDRO prevention and control measures for medical staff, effectively reduce the infection rate of MDRO in lung transplant recipients and the detection rate of MDRO on the environmental surface, which is worthy of widespread application.
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Objective To evaluate the efficacy and safety of tigecycline combined with cefoperazone-sulbactam sodium in the treatment of multi-/extensively-drug resistant Acinetobacter baumannii(MDRAB/XDRAB)associated central nervous system(CNS)infection,and to provide clinical evidence for antibiotic treatment of MDRAB/XDRAB-related intracranial disease.Methods The Wanfang Data Knowledge Service Platform,Chinese Biomedical Literature Database,VIP Chinese Science and Technology Journal Full-text Database,China National Knowledge Infrastructure(CNKI),Pubmed,Embase database,and Cochrane Library were searched to extract the literature of randomized controlled studies on tigecycline and cefoperazone sulbactam in the treatment of MDRAB/XDRAB CNS infection until September 1st,2022.The included studies were assessed for quality using the Cochrane Collaboration Risk of Bias assessment tool,and valid data were extracted and meta-analyzed using RevMan5.4 software.Results A total of 184 articles were screened and 4 Chinese RCTs were finally included,with a sample size of 267 cases.Meta-analysis showed that the overall efficacy of combination therapy for MDRAB/XDRAB CNS infection was better than monotherapy[OR = 4.30,95%CI =(1.93,9.58),P<0.01].Combination therapy had a better bacterial clearance[OR=4.20,95%CI=(2.08,8.48),P<0.01].And combination therapy resulted in a lower incidence of adverse effects[OR= 0.19,95%CI =(0.05,0.67),P<0.05].There was no apparent difference in cure rate between combination therapy and monotherapy(P>0.05).Conclusion Current evidence suggests that tigecycline combined with cefoperazone-sulbactam sodium may have better clinical efficacy and safety than monotherapy for MDRAB/XDRAB CNS infections.Limited by the number and quality of included studies,needs to be verified by more and higher-quality studies.
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Objective To investigate the attributable risk(AR)of Acinetobacter baumannii(AB)infection in criti-cally ill patients.Methods A multicenter retrospective cohort study was conducted among adult patients in inten-sive care unit(ICU).Patients with AB isolated from sterile body fluid and confirmed with AB infection in each cen-ter were selected as the infected group.According to the matching criteria that patients should be from the same pe-riod,in the same ICU,as well as with similar APACHE Ⅱ score(±5 points)and primary diagnosis,patients who did not infect with AB were selected as the non-infected group in a 1:2 ratio.The AR was calculated.Results The in-hospital mortality of patients with AB infection in sterile body fluid was 33.3%,and that of non-infected group was 23.1%,with no statistically significant difference between the two groups(P=0.069).The AR was 10.2%(95%CI:-2.3%-22.8%).There is no statistically significant difference in mortality between non-infected pa-tients and infected patients from whose blood,cerebrospinal fluid and other specimen sources AB were isolated(P>0.05).After infected with AB,critically ill patients with the major diagnosis of pulmonary infection had the high-est AR.There was no statistically significant difference in mortality between patients in the infected and non-infec-ted groups(P>0.05),or between other diagnostic classifications.Conclusion The prognosis of AB infection in critically ill patients is highly overestimated,but active healthcare-associated infection control for AB in the ICU should still be carried out.
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Objective To evaluate the clinical application value of matrix-assisted laser desorption ionization time-of-flight mass spectrometry(MALDI-TOF MS)in analyzing the homology of Acinetobacter baumannii(AB).Methods After excluding repetitive strains from multiple specimens of the same patient or environment,a total of 46 AB strains isolated from patients'sputum and environmental specimens of neurological intensive care unit(ICU)in a tertiary first-class general hospital from May 2020 to February 2021 were collected.Strains were detected by VITEK-MS mass spectrometer.Cluster analysis was performed by SARAMIS Premium software,and verified by multilocus sequence typing(MLST).Results Cluster analysis and comparison of MALDI-TOF MS and MLST found that among the 46 AB strains,39 were the type MS-a of MALDI-TOF MS,of which 22 strains were the clus-ter MT-A of MLST,including ST208(n=3),ST540(n=3),ST195(n=8),ST369(n=5),ST136(n=1),ST436(n=1)and ST1893(n=1);16 strains were MT-B,including type ST381(n=4),type ST469(n=11),and type ST938(n=1);one strain was cluster MT-C(ST1821);one strain of type MS-b was ST381;two strains of type MS-c were ST369;one strain of type MS-d was ST195;two strains of type MS-e were ST540 and ST369,respectively;one strain of type MS-f was STN1.Conclusion As a homology analysis method,MALDI-TOF MS still has certain limitations such as low consistency with MLST results,low resolution and specificity,thus cannot replace MLST technology.
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Objective To assess the risk factors for carbapenem-resistant Acinetobacter baumannii(CRAB)bloodstream infection(BSI)and 28-day short-term mortality in elderly patients,and provide reference for the pre-vention and treatment of CRAB BSI.Methods Clinical data of patients aged ≥60 years and diagnosed with AB BSI in a hospital in Yulin City from January 2013 to December 2022 were retrospectively analyzed,including demogra-phic and microbiological characteristics,as well as clinical outcomes of the patients.Variables which were significant in univariate analysis were selected for multivariate analysis using binary logistic regression model and Cox propor-tional hazards model.Independent risk factors for infection were further determined,and survival analysis was per-formed using Kaplan-Meier curve.Results A total of 150 patients were included in the study,out of which 16 pa-tients(10.7%)had CRAB BSI and 134 had carbapenem-sensitive AB(CSAB)BSI.The 28-day short-term mortali-ty of AB BSI in elderly patients was 15.3%(23/150,95%CI:9.6%-21.1%),and the short-term mortality of CRAB BSI was higher than that of CSAB([56.3%,9/16]vs[10.4%,14/134]).Deep venous catheterization(OR:15.598,95%CI:1.831-132.910)and combined infections of other sites(OR:15.449,95%CI:1.497-159.489)were related to CRAB BSI in elderly patients.The independent risk factors for 28-day mortality in elderly patients with AB BSI were hemodialysis(OR:11.856,95%CI:2.924-48.076),intensive care unit admission(OR:9.387,95%CI:1.941-45.385),and pulmonary infection being suspected source of bacteremia(OR:7.019,95%CI:1.345-36.635).Conclusion The occurrence of CRAB BSI in elderly patients is related to the combined infection of other sites and deep vein catheterization.Hemodialysis,admission to ICU,and pulmonary infection being suspected source of bacteremia are independent risk factors for the prognosis of AB BSI in elderly patients.
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Objective To explore the application of metagenomic next-generation sequencing(mNGS)technology in the investigation of healthcare-associated infection(HAI)outbreaks of carbapenem-resistant Acinetobacter bau-mannii(CRAB).Methods Pathogenic detection by mNGS and conventional pathogen culture were performed on 5 patients in the intensive care unit(ICU)of a hospital from June 8 to 22,2023 from whom CRAB were detected.Microbial sampling was carried out in potentially contaminated environment.Bacterial culture,identification,and antimicrobial susceptibility testing were conducted.Comprehensive control measures were taken,and the effect was evaluated.Results The time required for reporting results by mNGS was shorter than the culture time([3.92± 1.05]days vs[6.24±0.25]days,P<0.001).CRAB was isolated from the specimens of 5 patients.mNGS de-tected OXA-23 resistance genes from all patients.After comprehensive assessment by experts,4 patients were HAI and 1 patient was due to specimen contamination.According to the definition from Guidelines for HAI outbreak control,this event was considered an outbreak of HAI.The monitoring results of environmental hygiene showed that the detection rate of CRAB in the environment during the outbreak was 51.30%(59/115),mainly from the hands of health care workers and the surface of ventilators.After implementing multidisciplinary infection control measures,clinicians'hand hygiene compliance rate and implementation rate of ventilator disinfection increased from 40.83%(49/120)and 33.33%(16/48)to 82.61%(95/115)and 83.33%(30/36),respectively.The prognosis of patients was good,and no new case emerged during subsequent monitoring.The outbreak of HAI in this hospital has been effectively controlled.Conclusion mNGS is characterized by high precision,less time consumption,and high accuracy,and can be applied to the prevention and control of HAI outbreak and the study of antimicrobial-re-sistant genomes.It is of great significance for the anti-infection treatment of patients with multidrug-resistant orga-nism infection as well as the formulation of HAI prevention and control measures.Continuous improving disinfec-tion effectiveness and hand hygiene compliance is important for preventing and controlling CRAB infection.
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Objective To investigate the environmental contamination related to first patient with carbapenem-re-sistant Acinetobacter baumannii(CRAB)infection and the infection status of relevant patients in a newly established intensive care unit(ICU)of a hospital in Tibetan area,and analyze the transmission risk.Methods From the ad-mission in ICU of a patients who was first detected CRAB on November 15,2021 to the 60th day of hospitalization,all patients who stayed in ICU for>48 hours were performed active screening on CRAB.On the 30th day and 60th day of the admission to the ICU of the first CRAB-infected patient,environment specimens were taken respectively 2 hours after high-frequency diagnostic and therapeutic activities but before disinfection,and after disinfection but before medical activities.CRAB was cultured with chromogenic culture medium.Results Among the 13 patients who were actively screened,1 case was CRAB positive,he was transferred from the ICU of a tertiary hospital to the ICU of this hospital on November 19th.On the 40th day of admission to the ICU,he had fever,increased frequency for sputum suction,and CRAB was detected.The drug sensitivity spectrum was similar to that of the first case,and he also stayed in the adjacent bed of the first case.64 environmental specimens were taken,and 9 were positive for CRAB,with a positive rate of 14.06%,8 sampling points such as the washbasin,door handle and bed rail were positive for CRAB after high-frequency diagnostic and therapeutic activities.After routine disinfection,CRAB was detected from the sink of the washbasin.Conclusion For the prevention and control of CRAB in the basic-level ICU in ethnic areas,it is feasible to conduct risk assessment on admitted patients and adopt bundled prevention and con-trol measures for high-risk patients upon admission.Attention should be paid to the contaminated areas(such as washbasin,door handle,and bed rail)as well as the effectiveness of disinfection of sink of washbasin.
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Objective To study the activity of ten kinds of antipyretic-antidotal traditional Chinese medicine(TCM),including radix tinosporae.herb of blin conyza and turmeric,against extensively drug-resistant Acineto-bacter baumannii(XDR-AB)infection,screen out the extracts of antipyretic-antidotal TCM which have in vivo anti-infection activity,provide a research basis for the discovery of novel antimicrobials against XD-RAB infection.Methods Ten antipyretic-antidotal TCM were extracted with water,50%ethanol and 95%ethanol respectively,and TCM extracts with different concentrations were prepared,which were co-incubated with the model of XDR-AB-infected Caenorhabditis elegans previously optimized by the research group.The in vivo activity of antipyretic-antidotal TCM against XDR-AB infection was judged through the survival rate of Caenorhabditis elegans.Results With the increase of concentration of turmeric and cortex pseudolaricis extracts,the survival rate of XDR-AB-infec-ted nematodes continued to improve.The water extract,50%ethanol extract,and 95%ethanol extract of turmeric at a concentration of 1 000 μg/mL could increase the survival rates of XDR-AB-infected Caenorhabditis elegans to 54.2%(compared to the negative control group,P<0.001),18.8%,and 13.3%,respectively.The water ex-tract,50%ethanol extract,and 95%ethanol extract of cortex pseudolaricis at a concentration of 1 000 μg/mL could increase the survival rates of XDR-AB-infected Caenorhabditis elegans to 47.4%(compared to the negative control group,P<0.001),23.8%,and 15.8%,respectively.Conclusion The water extracts of turmeric and cortex pseudolaricis have good activity against XDR-AB infection,and their main chemical components can be tested for in vitro antimicrobial efficacy to discover novel antimicrobial agents against XDR-AB infection.
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Introducción: Acinetobacter baumannii se asocia a una alta morbimortalidad, una mayor estancia hospitalaria y, por lo tanto, un gran impacto sanitario. Objetivos: comparar la respuesta clínica y la supervivencia empleando como tratamiento antibiótico colistina endovenosa frente a colistina combinada con altas dosis de ampicilina/sulbactam ante infecciones por A. baumannii multirresistente en las salas de cuidados intensivos de adultos del Hospital Nacional (Itauguá, Paraguay) Materiales y métodos: se aplicó un diseño de cohortes retrospectivas donde se analizó la respuesta clínica y laboratorial, la supervivencia a los 14 días y la tasa de mortalidad en pacientes tratados con colistina 5 mg/kg/día como monoterapia frente a terapia combinada de colistina 5 mg/kg/día más ampicilina/sulbactam 9 gramos cuatro veces al día. Las variables se obtuvieron de los expedientes clínicos de pacientes ≥18 años infectados con A. baumannii multirresistente. Resultados: se incluyeron 163 pacientes, con edad media de 50 ± 17 años, siendo el 61,96% de sexo masculino. El 69,33% presentó neumonía asociada a ventilación mecánica, el 21,47% bacteriemia, el 5,52% ventriculitis y el 3,68% infección relacionada a vía venosa central. Una cohorte de 88 pacientes recibió monoterapia con colistina endovenosa y otra de 75 pacientes la terapia combinada de colistina endovenosa más dosis altas de ampicilina/sulbactam. No se encontró diferencias en la puntuación de APACHE II entre ambas cohortes. La cohorte con tratamiento combinado demostró superioridad estadísticamente significativa al presentar mejoría clínica y laboratorial a las 72 hs, menor necesidad de vasopresores, mejor sobrevida a los 14 días y menor nefrotoxicidad. La tasa de mortalidad global fue del 45,40%. Conclusión: la terapia combinada de colistina endovenosa con dosis altas de ampicilina/sulbactam en infusión prolongada se encontró relacionada a mejoría clínica temprana, menor tiempo de requerimiento de vasopresores y asistencia respiratoria mecánica, mayor supervivencia a los 14 días y menor nefrotoxicidad.
Introduction: Acinetobacter baumannii is associated with high morbidity and mortality, longer hospital stays, and, therefore, a great health impact. Objectives: To compare the clinical response and survival using intravenous colistin as antibiotic treatment versus colistin combined with high doses of ampicillin/sulbactam in multidrug-resistant A. baumannii infections in the adult intensive care units of the National Hospital (Itauguá, Paraguay). Materials and methods: A retrospective cohort design was applied to analyze the clinical and laboratory response, 14-day survival, and mortality rate in patients treated with colistin five mg/kg/day as monotherapy versus combined colistin therapy five mg/kg/day plus ampicillin/sulbactam 9 grams four times a day. The variables were obtained from the clinical records of patients ≥18 years old infected with multidrug-resistant A. baumannii. Results: One hundred sixty-three patients were included, with a mean age of 50 ± 17 years, 61.96% male. Pneumonia associated with mechanical ventilation was present in 69.33%, bacteremia in 21.47%, ventriculitis in 5.52% and infections related to the central venous line in 3.68%. A cohort of 88 patients received monotherapy with intravenous colistin and another of 75 patients received combined therapy with intravenous colistin plus high doses of ampicillin/sulbactam. No differences were found in the APACHE II score between both cohorts. The cohort with combined treatment demonstrated statistically significant superiority by presenting clinical and laboratory improvement at 72 hours, less need for vasopressors, better survival at 14 days, and less nephrotoxicity. The overall mortality rate was 45.40%. Conclusion: The combined therapy of intravenous colistin with high doses of ampicillin/sulbactam in prolonged infusion was related to early clinical improvement, shorter time requiring vasopressors and mechanical ventilation, greater survival at 14 days, and less nephrotoxicity.
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Background: The overwhelming advance of antimicrobial resistance demands the incorporation of new antibiotics and effective alternative treatments, and among the latter, blue light phototherapy. The objective of this study was to evaluate the photoinactivation effect of irradiation with blue light (405 nm) on extensively drug-resistance (XDR) Gram-negative bacteria from healthcare-associated infections Methods: A lighting unit was made using a 50W LED fitted to a condenser lens to create an irradiance gradient. After characterization of the lamp and standardization of microbiological procedures, bacterial inocula of 1.5×107 CFU of 40 bacterial strains: 27 Enterobacterales and 13 Pseudomonadales were subjected to irradiation for 15 minutes with blue light. The results were analysed with the SPSS program and by applying the Shapiro-Wilk and Mann-Whitney tests. Survival rates were also calculated. Results: 82.5% of the strains were photoinactivated, with inhibition thresholds between 86 and 126 J/cm2 for most of the Enterobacterales and below 86 J/cm2 in large part of the Pseudomonadales, these being the most sensitive group. 17.5% of the strains showed tolerance to irradiation thresholds up to>171 J/cm2. The survival rate decreased as the halo of inhibition of bacterial growth increased. The photoinactivating effect of blue light on the bacteria studied was a characteristic independent of the complexity of the resistance pattern that these strains presented. Conclusions: The findings obtained show that blue light has an important photoinactivating effect against XDR Gram-negative bacteria of nosocomial origin and can be considered as a future therapeutic alternative to contain the phenomenon of antimicrobial resistance.
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Background & objectives: Multidrug-resistant (MDR) Acinetobacter baumannii is a serious threat for human health worldwide. The studies on agents targeting A. baumannii are imperative due to identified A. baumannii co-infections in COVID-19. Bacteriophages are promising antibacterial agents against drug-resistant bacteria. This study intended to isolate bacteriophages against MDR A. baumannii from the water of river Ganga, to be used potentially as therapeutic and disinfectant particles. Methods: Acinetobacter phages were isolated from the Ganga water collected from Kanpur and further tested on 50 MDR A. baumannii isolates to determine host range. The phages were morphologically characterized by transmission electron microscopy. The disinfectant property of the isolated phages was tested by spraying of bacteriophage cocktail on MDR A. baumannii contaminated plastic surface, analyzed by colony-forming unit (CFU) and bioluminescence assay (adenosine triphosphate monitoring). Results: A total of seven bacteriophages were isolated against MDR A. baumannii. The bacteriophages lysed three MDR A. baumannii isolates out of 50 tested, showing narrow host range. Electron microscopy revealed hexagonal heads and long tails of bacteriophages, belonging to order Caudovirales. The bacteriophage cocktail reduced the MDR A. baumannii load efficiently on plastic surface, evidenced by reduction in CFUs and bioluminescence. Interpretation & conclusions: The findings of this study suggest that the isolated bacteriophages are potential lytic agents for MDR A. baumannii clinical isolates, and may be used as potential therapeutic agents as well as disinfectant to combat MDR A. baumannii with due consideration to phage host specificity, with further characterization.n
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Acinetobacter baumannii (AB) es un bacilo gram negativo, no fermentador,con frecuencia oportunista, ubicuo en el medio ambiente, con capacidad para sobrevivir en condiciones medioambientales adversas promoviendo su persistencia y diseminación en diferentes áreas de un hospital. Ha sido relacionado con múltiples brotes de infecciones asociadas al cuidado de la salud como neumonía, bacteriemias, contaminación de heridas quirúrgicas o infecciones del tracto urinario, especialmente entre pacientes con comorbilidades graves, como aquellos que motivan el ingreso a unidades de cuidados intensivos (UCI). Las cepas más problemáticas son aquellas resistentes a los carbapenémicos, resistencia causada por enzimas de la clase de las oxacilinasas (bla OXA) cromosómicas o plasmídicas y más recientemente bla NDM-1. La aparición de estas cepas deja escasos antimicrobianos activos (colistin, minociclina, tigeciclina; amikacina) que son limitados en su eficacia y su uso se asocia con toxicidad. A esto se agrega, como en la paciente que se describe, que desarrolló una meningitis posquirúrgica, la limitada capacidad de difusión en el sistema nervioso central (SNC) de estas últimas opciones. Una de las alternativas terapéuticas, es buscar asociaciones como sulbactam/avibactam que mostraron una adecuada actividad sinérgica y bactericida en asilamientos resistentes a ampicilina/sulbactam en base a una significativa reducción de la CIM que permite administrar dosis habituales, con mejor tolerancia y lograr concentraciones terapéuticas en SNC. Se presenta una paciente que desarrolló una meningitis posquirúrgica debida a una cepa de AB multirresistente.
Acinetobacter baumannii (AB) is a non-fermenting gram-negative bacillus, largely opportunistic, ubiquitous in the environment, with the ability to survive in adverse environmental conditions, promoting its persistence and dissemination in different areas of the hospital. It has been implicated in many outbreaks of healthcare-associated infections such as pneumonia, bacteremia, surgical wounds contamination, or urinary tract infections, especially among patients with previous severe illnesses such as those requiring admission to intensive care units (ICU). The most problematic strains are those resistant to carbapenems, resistance caused by chromosomal or plasmid oxacillinase class (bla OXA), and more recently bla NDM-1. The appearance of these strains leaves few active antimicrobials (Colistin, Minocycline, Tigecycline; Amikacin) that are limited in their efficacy and toxic. To this we must add, as is the case of our patient who presented post-surgical meningitis, the limited diffusion capacity in the central nervous system (CNS) of these last options. One of the therapeutic alternatives is to search for synergistic associations such as sulbactam/avibactam that showed rapid synergistic and bactericidal activity in isolates resistant to ampicillin/sulbactam due to a significant reduction in its MIC, which allows us to administer usual, better tolerated doses that reach therapeutic concentrations in CNS. Here, we present a patient who developed a post-surgical meningitis due to multiresistant AB
Subject(s)
Humans , Female , Adult , Sulbactam/therapeutic use , Acinetobacter baumannii , Drug Synergism , Meningitis/therapyABSTRACT
Aims: Our proposal aimed to evaluate Acyl Homoserine Lactones (AHL) as a functional marker for Multi drug resistant (MDR) potential in clinical isolates of Acinetobacter baumannii. We investigated the AHL production potential of clinical isolates using a biosensor assay directly on a commonly used agar media. Place and Duration of Study: Department of Molecular Diagnostics and Biomarkers, Gleneagles Global Hospitals, Lakdikapul, Hyderabad-500004. Methodology: Antimicrobial drug sensitivity testing (AST) was performed on 72 clinical isolates of A. baumannii against two front-line antibiotics, Imipenem (10µg) and Meropenem (10µg), by Kirby-Bauer disk diffusion method. Production of long chain Acyl Homoserine lactone (AHLs) in the clinical isolates of A. baumannii was tested by cross streaking with the biosensor Chromobacterium violaceum mutant strain CV026 and Agrobacterium tumefaciens (NTL4pZLR4) by agar plate diffusion assay. Screening and identification of the quorum sensing mediator gene abaI was done by PCR to confirm its presence in all the 72 clinical isolates. Results: Out of the 72 clinical isolates, 58 were Carbapenem resistant Acinetobacter baumannii (CRAB) and 14 were Carbapenem sensitive Acinetobacter baumannii (CSAB) for AST by agar disc diffusion method. None of our isolates produced short chain AHLs whereas all the isolates could produce varying amounts of long chain AHLs. Genotypic confirmation of AHL gene was obtained by abaI gene PCR. Conclusion: Carbapenems are the front-line antibiotics used to treat gram negative bacterial infections in emergencies and in the critical care units of hospitals. Clinical isolates A. baumannii has innate resistance to several antibiotics due to various mechanisms, biofilms forming the first line of defense against antibiotics for the bacterium. Our study used AST to carbapenem as the leading marker for MDR, assuming the innate resistance of A. baumannii to other beta lactam antibiotics. Our study brought out certain important observations namely: a) All clinical isolates of A. baumannii produced Quorum Sensing signal molecules, the AHLs b) the clinical isolates of A. baumannii did not produce any short chain AHLs b) All the clinical isolates of A. baumannii produced long chain AHLs c) AHL production is not specific to carbapenem drug resistance because even CSAB isolates produced AHL d) AHL production is inherent to all clinical isolates of A. baumannii and it apparently indicates an underlying biofilm potential and MDR trait in these A. baumannii isolates. e) AHLs could be a universal marker for revealing MDR trait and biofilm potential in clinical microbiology AST profiling protocols.
ABSTRACT
Background: Indiscriminate use of antibiotics has resulted in the emergence of resistant pathogens. Ethylenediaminetetraacetic acid (EDTA) is a well-known chelating agent. EDTA is also a potentiating and sensitizing agent when combined with antibiotics. Objectives of current study were to examine the antibacterial activity of Ceftriaxone+Sulbactam+ Disodium EDTA against pathogens isolated from urine, blood, and respiratory secretions (sputum, tracheal tube aspirates) and compare it with other antibiotics. Methods: The study was a retrospective study conducted in a tertiary care hospital between January 2019 and December 2019. Gram-negative isolates were obtained from clinical samples of urine, blood and respiratory samples were tested for susceptibility to different antibiotics and also for ESBL and MBL production Results: Respiratory isolates: Against Acinetobacter baumannii, 64% of isolates were sensitive to Ceftriaxone Sulbactam EDTA. Highest resistance rates were observed with Piperacillin tazobactam, amoxicillin clavulanate and Cefoperazone+Sulbactam. All Clinical isolates of Pseudomonas were sensitive to Ceftriaxone Sulbactam EDTA. Blood isolates: 25% isolates of Acinetobacter were sensitive to Ceftriaxone Sulbactam EDTA as compared to just 13% susceptibility for Cefoperazone+Sulbactam Urine isolates: 78% E. coli were sensitive to Ceftriaxone Sulbactam EDTA. Conclusions: The combination of ceftriaxone, sulbactam and disodium edetate was effective even against pathogens isolated from isolates from respiratory secretions, blood and urine resistant to other antibiotics.
ABSTRACT
@#As a Gram-negative bacillus,Acinetobacter baumannii is one of the main opportunistic pathogens causing nosocomial infection,and mainly infects various human organs such as lungs,which finally causes bacteremia,pneumonia and other diseases,and seriously threatens lives of patients.People with weak immunity are the main susceptible people.The strain has strong stress resistance and multiple antibiotic resistance,making its infection a difficult problem in clinical treatment.The outer membrane complex(OMC),outer membrane vesicles(OMVs),secretory system and lipopolysaccharide of A.baumannii play an important role in the process of infection of host cells.At present,the vaccines developed against these pathogenic components can play a certain role in preventing and treating A.baumannii infection,and have a good application prospect.In this paper,the pathogenesis of A.baumannii and the current situation of vaccine development are reviewed,so as to provide a reference for the development of novel prevention and treatment methods of it in clinic.