Treatment Of Acinetobacter Baumannii Research Articles

Treatment of Acinetobacter baumannii by Specialized ϕTZ Bacteriophage and Studying of pH Effect on Bacteriophage Stability and Efficacy

In general, one of the most important and dangerous pathogens facing human society is the resistance of different types of bacteria to many types of antibiotics. Acinetobacter baumannii is one of the most dangerous pathogens because of its prevalence in the hospital environment, being among the normal flora of bacteria inside the body also they are opportunistic bacteria due to their ability to turn into pathogenic bacteria when there is any weakness in the body’s immunity thus causes many diseases such as pneumonia, inflammation of the central nervous system and many different diseases. Because of the high ability of A. baumannii to acquire genes responsible for resistance to all antibiotics, including carbapenems, from the environment, it has become necessary to discover new methods to limit the spread of this bacteria and treat them. Among these methods is the treatment by bacteriophages then studying the physical properties, and one of the important characteristics that must be studied is the best pH that maintains the stability and effectiveness of the bacteriophage specialized in treating A. baumannii (ϕTZ), which belongs to the family Myoviridae. The pH 6.0 was found to maintain the best activity in the lysis of bacteria and stability of Bacteriophage. As well as, it was able to survive 100%.

Observation of clinical efficacy of the cefoperazone/sulbactam anti‐infective regimen in the treatment of multidrug‐resistant Acinetobacter baumannii lung infection

Sulbactam and sulbactam-containing β-lactam antibiotics are often used in the treatment of Acinetobacterbaumannii. We aimed to further examine the clinical efficacy of a cefoperazone/sulbactam anti-infective regimen in multidrug-resistant A.baumannii (MDRAB) lung infections. We conducted a retrospective analysis among patients with MDRAB lung infection and complete data who were treated at the geriatric intensive care unit of Jiangsu Province Hospital from January 2018 to December 2020. We collected general information, including age, sex, APACHE II score, anti-infective course, comorbid infections in other sites, other pathogens, cefoperazone/sulbactam regimen and concomitant medications, and adverse reactions. We used microbiological changes before and after treatment to assess microbiological efficacy, defined as microbial eradication and reduction. 121 patients were included, among which 96 (79.34%) were men and 25 (20.66%) were women. The median age was 76 (interquartile range [IQR] 62.5-83) years, median APACHE II score was 22 (IQR 19-26), and median treatment course was 8 (IQR 5-12.5) days. Among these patients, tigecycline was concomitantly used in 52 patients and the sulbactam dose was increased to 4g and above in 27 patients. The microbiological efficacy of conventional cefoperazone/sulbactam with/without tigecycline in MDRAB decreased with each consecutive year and a reduction in efficacy was linearly correlated with year, which was both statistically significant (p=0.039, 0.030, respectively). In 2020, the microbiological efficacy of a higher sulbactam dose combined with tigecycline was 75%, which was a significant improvement over the conventional dose (p=0.028). The 3-year data showed that the microbiological efficacy of conventional cefoperazone/sulbactam 3g eight hourly (q8h) without tigecycline was 32% and efficacy increased to 57.9% when the sulbactam dose was increased. Hence, the increased sulbactam dose significantly improved efficacy in MDRAB lung infection (p=0.049). Different doses of sulbactam combined with tigecycline increased the microbiological efficacy of MDRAB but the differences were not statistically significant. A cefoperazone/sulbactam-based anti-infective regimen showed some efficacy in MDRAB lung infection, but the microbiological efficacy of a cefoperazone/sulbactam 3g q8h regimen decreased over time. Increasing the sulbactam dose to 4g or more can improve efficacy. Minimum inhibitory concentration (MIC)-guided personalized medicine may be a future research direction.

Contribution of zinc solubilizing bacterial isolates on enhanced zinc uptake and growth promotion of maize (Zea mays L.).

Zinc-solubilizing bacteria, namely Burkholderia cepacia and Acinetobacter baumannii (H1 and H3, respectively), able to grow in liquid basal medium supplemented with ZnO, Zn3 (PO4)2, and ZnSO4·7H2O (0.1%), showed plant growth promoting properties. The treatment of Acinetobacter baumannii (H3) solubilizes the ZnO (1.42ppm), Zn3 (PO4)2 (1.15ppm), and ZnSO4·7H2O (1.44ppm).The maximum solubilization of ZnSO4·7H2O (1.42ppm) was observed in Burkholderia cepacia (H1) after 15days. Organic acids produced by the bacteria decreased the pH of the medium and helped in Zn solubilization. In pot experiment on maize, Burkholderia cepacia (H1) treatment significantly enhanced plant height and root length in the presence of ZnO (2%) added in 10mL of inoculum in each pot. High-performance liquid chromatography (HPLC) analysis of maize root extract showed the presence of oxalic, maleic, tartaric, and fumaric acid after 60days of the experiment. Bacterial treatments enhanced sugar and protein level in maize plants and were 55.2 and 42.55µg/mL plant extract, respectively, under mixture of bacterial treatment. Hence, isolates H1 and H3 expressed highest potential throughout the experiments, as zinc solubilizers and plant growth-promoting strains. This study demonstrated that meticulous use of Zn-solubilizing bacterial strains could aid in enhanced plant growth and can be the potential bio-inoculants for biofortification of maize to overcome the problems of malnutrition.

Direct detection of Acinetobacter baumannii by loop-mediated isothermal amplification in patients with respiratory tract infection

Background Rapid detection and treatment of Acinetobacter baumannii which is a health-care-associated pathogen that causes outbreaks and frequently encountered in ICU patients on mechanical ventilation is very important. Aim The present study aimed to detect the frequency of A. baumannii in sputum sample by loop-mediated isothermal amplification (LAMP) assay in comparison with the different culture methods. Patients and methods In all, 200 sputum samples and 100 tracheal aspirates (TA) were included to detect the frequency of Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, A. baumannii, Pseudomonas aeruginosa, and Enterobacter spp. (ESKAPE) pathogens by cultural methods and to detect A. baumannii from sputum sample by LAMP assay comparing its results with CHROMagar Acinetobacter and conventional culture methods referring to the rate of multidrug-resistant A. baumannii. Results By conventional culture, positive culture was reported in 228/300 (76%) of all samples. A. baumannii and Klebsiella spp. were the most identified pathogens as they were detected in 27/145 (18.6%) and 19/145 (13%) of sputum samples and 19/83 (22%) and 43/83 (51.8%) of TA. Regarding culture on CHROMagar 46 isolates were identified as A. baumannii, 27 were from sputum sample, and 19 from TA. Out of 46 A. baumannii isolates multidrug-resistant A. baumannii were detected in 9/27 (33.3%) and 15/19 (78.9%) in sputum samples and TA, respectively. DNA of A. baumannii was detected in 28/200 (14%) by LAMP assay from sputum samples. Sensitivity and specificity of LAMP assay were 100 and 99.5% when compared with the conventional culture. Conclusion CHROMagar Acinetobacter and LAMP assay are cost-efficient methods in comparison to conventional culture. LAMP assay is distinguished from the others for its simplicity and rapid detection of pathogens.

Multidrug Resistant Acinetobacter baumannii: Resistance by Any Other Name Would Still be Hard to Treat.

Acinetobacter baumannii (AB) is an infamous nosocomial pathogen with a seemingly limitless capacity for antimicrobial resistance, leading to few treatment options and poor clinical outcomes. The debatably low pathogenicity and virulence of AB are juxtaposed by its exceptionally high rate of infection-related mortality, likely due to delays in time to effective antimicrobial therapy secondary to its predilection for resistance to first-line agents. Recent studies of AB and its infections have led to a burgeoning understanding of this critical microbial threat and provided clinicians with new ammunition for which to target this elusive pathogen. This review will provide an update on the virulence, resistance, diagnosis, and treatment of multidrug resistant (MDR) AB. Advances in bacterial genomics have led to a deeper understanding of the unique mechanisms of resistance often present in MDR AB and how they may be exploited by new antimicrobials or optimized combinations of existing agents. Further, improvements in rapid diagnostic tests (RDTs) and their more pervasive use in combination with antimicrobial stewardship interventions have allowed for more rapid diagnosis of AB and decreases in time to effective therapy. Unfortunately, there remains a paucity of high-quality clinical data for which to inform the optimal treatment of MDR AB infections. In fact, recently completed studies have failed to identify a combination regimen that is consistently superior to monotherapy, despite the benefits demonstrated in vitro. Encouragingly, new and updated guidelines offer strategies for the treatment of MDR AB and may help to harmonize the use of high toxicity agents such as the polymyxins. Finally, new antimicrobial agents such as eravacycline and cefiderocol have promising in vitro activity against MDR AB but their place in therapy for these infections remains to be determined. Notwithstanding available clinical trial data, polymyxin-based combination therapies with either a carbapenem, minocycline, or eravacycline remain the treatment of choice for MDR, particularly carbapenem-resistant, AB. Incorporating antimicrobial stewardship intervention with RDTs relevant to MDR AB can help avoid potentially toxic combination therapies and catalyze the most important modifiable risk factor for mortality-time to effective therapy. Further research efforts into pharmacokinetic/pharmacodynamic-based dose optimization and clinical outcomes data for MDR AB continue to be desperately needed.

Systematic Review of Antimicrobial Resistance of Clinical Acinetobacter baumannii Isolates in Iran: An Update.

Treatment of Acinetobacter baumannii has become a medical challenge because of the increasing incidence of multiresistant strains and a lack of viable treatment alternatives. This systematic review attempts to investigate the changes in resistance of A. baumannii to different classes of antibiotics in Iran, with emphasis on the antimicrobial activity of polymyxin B (PMB) and colistin (COL). Biomedical databases were searched for English-published articles evaluating microbiological activity of various antimicrobial agents, including PMB and COL. Then, the available data were extracted and analyzed. Thirty-one studies, published from 2009 to 2015, were identified which contain data for 3,018 A. baumannii clinical isolates. With the exception of polymyxins and tigecycline (TIG), there was a high rate of resistance to various groups of antibiotics, including carbapenems. The minimum inhibitory concentration (MIC) ranges for PMB and COL on A. baumannii isolates tested were 0.12-64 μg/ml and 0.001-128 μg/ml, respectively. Polymyxins showed adequate activity with no significant trends in the resistance rate during most of the study period. The incidence of resistance to TIG was estimated low from 2% to 38.4% among the majority of A. baumannii. The present systematic review of the published literatures revealed that multidrug-resistant (including carbapenem-resistant) strains of A. baumannii have increased in Iran. In these circumstances, the older antibiotics, such as COL or PMB, preferably in combination with other antimicrobials (rifampicin, meropenem), could be considered as the therapeutic solution against the healthcare-associated infections. Designing rational dosage regimens for patients to maximize the antimicrobial activity and minimize the emergence and prevalence of resistance is recommended.

Prevention and Treatment of Virulent Bacterial Biofilms with an Enzymatic Nitric Oxide-Releasing Dressing

The use of percutaneous medical devices often results in nosocomial infections. Attachment of microorganisms to the surfaces of these medical devices triggers biofilm formation, which presents significant complications to the health of a patient and may lead to septicemia, thromboembolism, or endocarditis if not correctly treated. Although several antimicrobials are commonly used for prevention of biofilm formation, they have limited efficacy against formed biofilms. In this study, we report the use of an enzymatic, gaseous nitric oxide (gNO)-releasing dressing for the prevention and treatment of Acinetobacter baumannii, methicillin-resistant Staphylococcus aureus, and Pseudomonas aeruginosa biofilms. Results show that the bactericidal activity against biofilms of the test strains was dependent on time and rate of gNO release from the dressing. Following 6 h of treatment, gNO-releasing dressings significantly inhibited the growth of test strains relative to vehicle control dressings, demonstrating eradication of bacterial concentrations of up to 10(5) CFU/cm(2). Complete cell death was observed for both prevention of biofilm formation and treatment of 24-h-grown biofilms after 6 h of treatment with the gNO-releasing dressings. Further, gNO-releasing dressings were more efficient against formed biofilms than other antimicrobial agents currently used. These results demonstrate that the gNO-releasing dressing can produce sufficient levels of gNO over a therapeutically relevant duration for maximal bactericidal effects against virulent bacterial strains known to cause nosocomial infections.