Multidrug Resistant Acinetobacter Baumanii Research Articles

Development of a Prediction Model for Acute Kidney Injury after Colistin Treatment for Multidrug-resistant Acinetobacter baumanii Ventilator-Associated Pneumonia: A Pilot Study

Objective: Multidrug-resistant Acinetobacter baumanii (MDR-AB) ventilator-associated pneumonia (VAP) is the major complication following hospital admission in Thailand, increasing morbidity and prolonging hospital stay duration. Treatment of MDR-AB VAP usually requires colistin which has highly nephrotoxic properties. Therefore, we aimed to develop a pilot prediction model for acute kidney injury (AKI) after colistin treatment.Material and Methods: We conducted a retrospective cohort study. All MDR-AB VAP patients who received colistin for at least 72 hours in Suratthani Hospital from January to July 2017 were eligible for inclusion. The primary outcome was the overall presence of AKI on days 3, 5 or 7 after colistin administration. Multivariable logistic regression analysis was used to develop the final prediction model.Results: Of 85 MDR-AB VAP patients, 51 (61%) developed AKI after colistin treatment. Nine factors, female, intensive care unit (ICU) admission, diabetes mellitus, systolic blood pressure (SBP), diastolic blood pressure (DBP), serum sodium, creatinine, blood urea nitrogen (BUN) and glomerular filtration rate were potential predictors of AKI. Multivariable logistic regression with backward stepwise selection revealed the best prediction model had four predictors: female, ICU admission, BUN, and DBP. The area under the receiver operating characteristic curve for the model in predicting AKI among MDR-AB VAP patients was 0.801 (95% confidence interval: 0.703, 0.898).Conclusion: The prediction model containing four predictors, female gender, ICU admission, BUN level, and DBP had fair to good performance in predicting AKI after colistin treatment among MDR-AB VAP patients.

Multi Drug Resistance and Multi Antibiotics Resistance Index of Acinetobacter baumannii Isolated from Hospitals in Port Harcourt Metropolis

Acinetobacter species are aerobic gram-negative bacilli that can cause healthcare-associated infections and can survive for prolonged periods in the environment. Also on the hands of healthcare workers, infection due to Acinetobacter species is a major challenge within the health care facilities and the community in general due to their high drug resistance. The study was aimed at detecting multi drug resistance and multi antibiotics resistance index (MARI) of acinetobacter baumannii isolated from hospitals in Port Harcourt meteropolis in Rivers State, Nigeria. The cross sectional study sampled randomly; as urine and wound swab samples were collected from patients. Acinetobacter spp was isolated using standard microbiological methods. Identification of A. baumannii isolates were done using Phynotypic methods such as culture on Lead Acinetobacter medium and conventional biochemical tests. Antimicrobial susceptibility test was done by Kirby Bauer’s disk diffusion method under Clinical Laboratory Standards Institute (CLSI, 2013) guide Suspect Acinetobacter species were further identified using polymerase chain reaction (PCR) and Sanger sequence typing methods. The results of confirmatory sequence typing of isolates showed that 9 of suspect Acinetobacter spp were A. baumannii. The results of this finding showed presence of A. baumannii species resistant to conventional antibiotics. All isolates demonstrated.MDR and XDR. MARI was high. (>0.2) indicating MDR and high risk. This study established high rate of multidrug resistant Acinetobacter baumanii. There is need for improved sanitary working condition and proper patients’ management to reduce the spread of this health care associated infection as well as a Search for new therapeutic alternative and policies to control the use of antibiotics.

Antimicrobial susceptibility pattern of an emerging multidrug resistant <em>Acinetobacter baumannii </em>from intensive care units of a tertiary care hospital

Introduction: Acinetobacter baumannii is one of the most challenging gram negative, lactose non-lactose fermenting bacilli with ability to cause nosocomial infections and develop resistance to many classes of antibiotics. Multidrug-resistant (MDR) A. baumannii is a well known agent causing life-threatening infections with limited therapeutic options. In recent years, the numbers of reported carbapenem-resistant Acinetobacter spp. are increasing, which has further narrowed the treatment options and emerging as extensively drug resistant (XDR) strain. There are only a few effective drugs such as colistin, polymyxin B, and tigecycline. But given the side effects and cost effectiveness, treatment of resistant nosocomial infections by A. baumanii is the biggest challenge for clinicians and policy makers all over the world.Aim:1. To know the antibiotic susceptibility pattern of Acinetobacter baumnii2. To know the prevalence of multidrug resistant Acinetobacter baumanii in critical areas of our tertiary care centre.Methodology: Clinical samples from both critical and non critical areas were processed routinely. Only non lactose fermenting colonies were included for the study and Acinetobacter baumanii isolates were identified using standard culture method and antibiotic susceptibility testing done by disk diffusion method.Results: Of 308 NLFs, 160 were Acinetobacter baumanii. 106 (66.25%) samples were from ICU and 54 (33.75%) from non critical areas. Commonest sample was endotracheal secretion 72(45%) followed by blood 38(23.75) and others. 70% of our isolates were resistant to Aminoglycosides. Among Fluoroquinolones, maximum resistance was shown for Ciprofloxacin. 59% of the isolates were resistant to Piperacillin-tazobactum and their resistance to Cephalosporins ranged from 60-80%. 42 (39.62% of our isolates were Multidrug resistant (MDR) and 19 (17.92%) were extensively drug resistant (XDR).Conclusion: Multidrug resistant and extensively drug resistant strains of Acinetobacter baumanii are on the rise and slowly getting established in our healthcare set up especially the critical areas. Treatment options are very few and limited. Thus leaving us with call to take stringent measures to stop the inadvertent use of antibiotics and to review our infection control policies.

Tigecycline susceptibility among multi-drug resistant bacteria: A 7-year retrospective study

The emergence and spread of multidrug-resistant bacteria (MDR) are major public health issues worldwide. The objective of this study is to evaluate the microbiological efficacy of tigecycline against multi-drug-resistant bacteria and to explore its potential place in clinical practice. A retrospective study was carried out over 7 years, from January 2015 to December 2021, at the Avicenne Military Hospital. Were collected all bacteriological samples received for diagnostic purposes at the microbiology laboratory. Tigecycline susceptibility was tested among 846 isolates among the 4293 isolates during the study period. The overall frequency of MDR bacteria was of 14,3%. 60% of the MDR bacteria isolated were susceptible, 35% were declared resistant and 5% were declared intermediate. Co-resistance levels in MDR bacteria are high. Tigecycline remained active in vitro on most of the MDR bacteria tested. The susceptibility rates for tigecycline found were respectively 76%, 57%, and 34%, for the ESBL Enterobacteriaceae strains, the CPEs, and the multi-drug resistant Acinetobacter baumanii strains. In this study, the MDR bacteria isolated showed overall satisfying susceptibility rates to tigecycline.

Five-Year Surveillance of Central Line Associated Bloodstream Infection in an Intensive Care Unit Population—A Retrospective Analysis

Background: Central venous catheters (CVCs) are essential to current intensive care unit (ICU) practices as a tool for treating critically ill patients. However, the use of CVCs is associated with substantial risk of infection. Central line associated bloodstream infection (CLABSI) is increasing in prevalence each year and is among the major causes of bloodstream infection in ICU patients. Therefore, investigating the epidemiology and risk factors of CLABSI in ICU patients is important. Objective: This study aimed to investigate the incidence rates, causative pathogens and risk factors of CLABSI in an ICU population. Methods: A retrospective observational study was performed in an ICU at Qilu Hospital of Shandong University in China from January 2016 to December 2020. Patients with at least one CVC were enrolled, and information relevant to CVC use was recorded. The prevalence was calculated, and related risk factors were analyzed. Results: A total of 1920 catheters were identified, 507 of which were eligible for analysis. For each of the years 2016-2020, the incidence rates of CLABSI were 1.91, 3.18, 1.69, 2.97 and 1.27 per 1000 catheter days, respectively. The yeast Candida albicans was the most prevalent pathogen (16 [(3.2%]), followed by Gram-positive methicillin-resistant Staphylococcus aureus (11 [2.2%]) and the Gram-negative multidrug-resistant pathogen Acinetobacter baumanii. Risk factors associated with CLABSI development were age, (p = 0.05), Charlson comorbidity index > 5 (p Candida albicans was the most common causative microorganism, which was followed by Gram positive methicillin resistant Staphylococcus, MDR K. pneumoniae and Acinetobacter baumanii.

Reducing Biofilm Infections in Burn Patients' Wounds and Biofilms on Surfaces in Hospitals, Medical Facilities and Medical Equipment to Improve Burn Care: A Systematic Review.

Biofilms in burns are major problems: bacterial communities rapidly develop antibiotic resistance, and 60% of burn mortality is attributed to biofilms. Key pathogens are Pseudomonas aeruginosa, methicillin-resistant Staphylococcus aureus, and multidrug-resistant Acinetobacter baumanii. Purpose: identify current and novel interventions to reduce biofilms on patients’ burns and hospital surfaces and equipment. Medline and Embase were searched without date or language limits, and 31 possible interventions were prioritised: phages, nano-silver, AgSD-NLs@Cur, Acticoat and Mepilex silver, acetic acid, graphene-metal combinations, CuCo2SO4 nanoparticles, Chlorhexidene acetate nanoemulsion, a hydrogel with moxifloxacin, carbomer, Chitosan and Boswellia, LED light therapy with nano-emodin or antimicrobial blue light + Carvacrol to release reactive oxygen species, mannosidase + trypsin, NCK-10 (a napthalene compound with a decyl chain), antimicrobial peptide PV3 (includes two snake venoms), and polypeptides P03 and PL2. Most interventions aimed to penetrate cell membranes and reported significant reductions in biofilms in cfu/mL or biofilm mass or antibiotic minimal inhibitory concentrations or bacterial expression of virulence or quorum sensing genes. Scanning electron microscopy identified important changes in bacterial surfaces. Patients with biofilms need isolating and treating before full admission to hospital. Cleaning and disinfecting needs to include identifying biofilms on keyboards, tablets, cell phones, medical equipment (especially endoscopes), sinks, drains, and kitchens.

Antimicrobial resistance pattern and molecular epidemiology of ESBL and MBL producing Acinetobacter baumannii isolated from hospitals in Minia, Egypt

ABSTRACT Introduction: Multidrug resistant (MDR) Acinetobacter baumanii (A. baumannii) strains have emerged as novel nosocomial pathogens threatening patients’ lives, especially in intensive-care units (ICUs). This study aims to determine the prevalence of carbapenemase genes and CTX-M-15 and the resistance pattern of carbapenemase producing isolates.Methods: A total of 530 clinical specimens were collected from patients suffering from different infections, antibiotic susceptibility test was performed using kirby-bauer disk diffusion method. ESβL production was detected phenotypically by double-disc synergy test (DDST). Carbapenemase production was tested by Modified Hodge Test (MHT). Then, these isolates were tested for MBL detection by disc potentiation test. Carbapenemase encoding genes (VIM, IMP, GIM and SPM, OXA-51, OXA-23 and OXA-143) and CTX-M-15 were tested by polymerase chain reaction (PCR).Results: Out of 530 samples, 20 bacterial isolates were identified as A. baumannii from different infectious cases, 35% of isolates were ESBL-producers. Eleven isolates were resistant to imipenem (4 isolates) and meropenem (7 isolates). All carbapenem resistant isolates were MHT positive. Nine (45%) isolates were confirmed as A. baumannii by OXA-51 (all were carbapenem resistant). Distribution of IMP, VIM, GIM and SPM, OXA-23, OXA-143 and CTX-M-15 by PCR were 55, 50, 50, 25, 35, 45 and 33% respectively.Conclusion: The high prevalence of resistance genes and the resistance pattern of the isolates indicate that the detection of ESBLs and MBLs phenotypically and genotypically with the study of the resistance pattern of the isolates is critically important for the surveillance of drug resistance in the hospital environment.

Health Care-Associated Infections in a Neurocritical Care Unit of a Developing Country.

Health care-associated infections (HAIs) in intensive care units (ICUs) specialized for neurocritical care (neurocritical care units [NCCUs]) are serious yet preventable complications that contribute significantly to morbidity and mortality worldwide. However, reliable data are scarcely available from the developing world. We aimed to analyze the incidence, epidemiology, microbial etiology, and outcomes of HAIs in an NCCU of a tertiary care teaching hospital in a high-income, developing country. In this 3-year retrospective cohort study, all patients admitted to the NCCU at the Ibn Sina Hospital in Kuwait for ≥ 2 calendar days were included. Patient demographics, hospitalization, and details of ICU-acquired infections were evaluated. Patient-related outcomes included hospital and ICU length of stay (LOS) and in-hospital mortality. Among 913 patients with a total of 4921 ICU days, 79 patients had 109 episodes of HAIs. The overall incidence rate and incidence density of HAIs were 11.9/100 patients and 22.1/1000 ICU days, respectively. Multiple episodes of infection were documented in 29% of patients. The most prevalent infections were urinary tract infections (UTIs; 40/109 [37%]), bloodstream infections (30/109 [28%]), and pneumonia (16/109 [15%]). Seventy-six percent of infections were device-associated infections. A total of 158 pathogens were isolated, of which 109 were Gram-negative bacteria. Of the 40 Gram-positive bacteria, 22 were staphylococci. Seven infections were due to Clostridium difficile. There were 15 Staphylococcus aureus isolates, 47% of which were methicillin resistant. Two episodes of UTIs were due to Candida species. There were 84 Enterobacteriaceae isolates, 24% of which were extended-spectrum β-lactamase producers. All Pseudomonas aeruginosa isolates were susceptible to aminoglycosides and carbapenems. Klebsiella species were the most common pathogen (45/158 [28%]), causing pneumonia (11/33 isolates [33%]), bloodstream infections (12/37 isolates [32%]), and UTIs (16/52 isolates [31%]). One episode of bloodstream infection was due to multidrug resistant Acinetobacter baumanii which was susceptible only to colistin. Only pneumonia was independently associated with mortality, while all HAIs that occurred were significantly associated with a prolonged ICU LOS. This is the first HAI surveillance study in an NCCU in Kuwait, and our results demonstrate the burden of HAIs on the neurologically injured patient, regardless of the site of infection. The high prevalence and resistant profile of HAIs in an NCCU in a developing country relative to a developed country has important implications for patient safety and emphasizes the need to strengthen collaboration between NCCU teams and infection control teams to prevent serious complications in this setting.

PHAGE COCKTAILS AGAINST HIGHLY MULTI-DRUG RESISTANT ACINETOBACTER BAUMANII

Background:Phage therapy is a potential alternative treatment for infections caused by many bacterial species such as Acinetobacter baumannii (A. baumannii), a significant nosocomial pathogen, has evolved resistance to almost all conventional antimicrobial drugs in poor hygiene and conflicts areas like Iraq. Objective:Isolate and apply bacteriophages as alternative therapeutic agents against extensively drug-resistant (XDR) and pan-drug-resistant A. baumannii and evaluation extracted native endolysin activity. Methods:Twenty-three bacterial samples were collected in Al-Imamein Al-kadhimein Medical City hospital. Phages were isolated from different regions in Baghdad city including (soil, sewage, irrigation channels). Native endolysin was extracted from highly lytic phage that produced halo-like appearance around inhibition zone. Results:Out of 50 isolates, 23 isolates (46%) of XDR, pan-drug resistant (PDR) A. baumanii have been isolated from patients with various infections. 136 lytic phages specific to A. baumanii were isolated. Each bacterial isolate was sensitive to at least one lytic phage. Phage cocktails were formulated and were shown remarkably minimize the bacterial resistance to individual lytic phages. In addition, the endolysin native activity of lytic phages specific to A. baumanii evaluated in this study revealed a potent antibacterial activity (> 1 log) reduction of bacterial density in just one hour of endolysin treatment. Conclusion: Phage therapy assessed in this study was shown ability to efficiently solve the problems of “superbug” bacteria by lysing effectively most XDR, PDR bacteria in vitro. And, phage cocktails were shown to be superior over single-phage preparations in treating A. baumanii with much less resistance rate to therapeutic phages. Furthermore, intrinsic activity of native endolysin revealed promising results to tackling superbug pathogens. Keywords: Phage, Phage cocktails, Acinetobacter, native endolysin, extensively drug-resistant (XDR), and pan-drug resistant (PDR) Citation: Jasim HN, Abdul-Ameer AS. Phage cocktails against highly multi-drug resistant Acinetobacter baumanii. Iraqi JMS. 2018; 16(4): 357-371. doi: 10.22578/IJMS.16.4.2

1266. Multifaceted Infection Control Strategies to Control Multidrug-Resistant Acinetobacter baumanii in Adult Intensive Care Unit in a Tertiary Hospital in Eastern Region, Saudi Arabia

BackgroundMultidrug-resistant Acinetobacter baumanii (MDR-AB) has emerged globally as a significant pathogen in hospitals. During 2010, our hospital experienced an increase of MDR-AB in Adult intensive care unit (ICU). Our adult ICU is consists of 10 acute care beds. The hospital is a tertiary institution located in Eastern region of Saudi Arabia. Multidisciplinary team was formed to implement and determine the effect of multifaceted strategies in controlling MDR-AB.MethodsActive surveillance culture (ASC) was initiated to determine the prevalence rate of MDR-AB per 1,000 patient-days (PD). Using ASC, which was done during admission in ICU, after 48 hours of admission and every week for all patients if there is a positive MDR-AB case, acquisition rate of MDR-AB was calculated per 1,000 PD. Average daily colonization pressure was also monitored. In addition, a multifaceted infection control strategies were carried out. These include hand hygiene, contact isolation, cohorting of patients, Chlorhexidine bath, and environmental cleaning and disinfection. Compliance with hand hygiene was observed using direct observation method. We use the Fluorescent Gel Method for evaluating the thoroughness of disinfection and cleaning for environmental surfaces.ResultsHand hygiene compliance of HCWs initially was 89%, in 2017 was increased to 98%. Daily Chlorhexidine bath was adopted for all patients in ICU. Initially, the compliance for thoroughness of disinfection and cleaning is 84.6% it was increased to 92% in 2013–2017. Prevalence rate of MDR-AB was 20.7/1,000 PD in 2010, it was decreased by 50% in 2011–2012. In 2017, declined to 0.9/1,000 PD. MDR-AB acquisition rate was 11.8/1,000 PD in 2010, it was decreased by 57% in 2011–2012. In 2017, dropped to 0.6/1,000 PD. Average daily colonization pressure was 0.21 in 2010. In 2011–2012, it was decreased by 31%. In 2017, it was reduced to 0.02. Death rate among MDR-AB patient in 2010 was 25.7%. It was decreased to 14% in 2011–2012. In 2017, an enormous drop to 0% was achieved.ConclusionImplementing these multifaceted strategies help in controlling MDR-AB in our hospital. The commitment and adherence of the HCW to all infection control strategies are essential in sustaining low prevalence rate and acquisition rate of MDR-AB.Disclosures All authors: No reported disclosures.

Multidrug resistance E-ESKAPE strains isolated from blood cultures in patients with cancer

To describe the trend of multidrug resistant (MDR) strains isolated from blood in patients with cancer from 2005 to 2015. 33 127 blood cultures were processed by retrospective analysis. Identification and antimicrobial sensitivity were performed through automated methods: WaLK away (Siemens Labora- tory Diagnostics) and BD Phoenix (Becton, Dickinson and Company). Resistant strains were determined according to the minimum inhibitory concentration, following the parameters of the Clinical and Laboratory Standards Institute (CLSI). Of 6 397 isolates, 5 604 (16.9%) were positive; 3 732 (58.4%) Gram- bacilli; 2 355 (36.9%) Gram+ cocci; 179 (2.7%) yeasts, and 126 (1.9%) Gram+ bacilli. Escherichia coli (n=1 591, 24.5%) was the most frequent bacteria, with 652 (41%) strains being extended-spectrum beta-lactamases producers (ESBL); of Enterococcus faecium (n=143, 2.1%), 45 (31.5%) were vancomycin resistant; of Staphylococcus aureus (n=571, 8.7%), 121 (21.2%) methicillin resistant (MRSA); of Klebsiella pneumoniae (n=367, 5.6%), 41 (11.2%) ESBL; of Acinetobacter baumanii (n=96, 1.4%), 23 (24%) MDR, and of Pseudomonas aeruginosa (n=384, 5.6%), 43 (11.2%) MDR. MDR strains were significantly more frequent in patients with hematological malignancies, compared to those with solid tumors: MRSA (OR=4.48, 95%CI 2.9-6.8), ESBL E. coli(OR=1.3, 95%CI 1.10-1.65) and MDR Acinetobacter baumanii (OR=3.2, 95%CI 1.2-8.3). We observed significantly higher isolations of E-ESPAKE MDR strains in patients with hematological malignancies.

Green synthesized silver nanoparticles by marine endophytic fungus Penicillium polonicum and its antibacterial efficacy against biofilm forming, multidrug-resistant Acinetobacter baumanii

Acinetobacter baumanii, a gram-negative, non-motile, encapsulated coccobacillus which causes infections worldwide. The objective of this study was to find a fungal strain that could be utilized to biosynthesize antibacterial silver nanoparticles (AgNPs) against Acinetobacter baumanii. The present investigation explains rapid and extracellular biosynthesis of silver nanoparticles by the algicolous endophytic fungus, Penicillium polonicum, isolated from the marine green alga Chetomorpha antennina. The obtained silver nanoparticles were characterized by UV-Vis spectroscopy, Raman spectroscopy, Fourier transformation infrared (FTIR), and Transmission electron microscopy (TEM). The SNPs showed a characteristic UV- visible peak at 430 nm with an average size of 10–15 nm. As evident from the FTIR and Raman spectra, possibly the protein components of fungal extract have caused the reduction of silver nitrate. Parametric optimization, including the concentration of AgNO3, ratio of cell filtrate and AgNO3, fungal biomass, reaction time, pH, and presence of light, was done for rapid AgNPs production. The antibacterial efficacy of AgNPs against multi-drug-resistant, biofilm-forming Acinetobacter baumanii, was evaluated by well diffusion assay. The Minimum inhibitory concentration (MIC) of AgNP was 15.62 μgml−1 and the minimum bactericidal concentration (MBC) was 31.24 μgml−1. Killing kinetic assay revealed complete killing of the bacterial cells within 6 h. Log reduction and percent survival of bacterial cells were analyzed from killing kinetic study. Bactericidal nature of synthesized nanoparticles was confirmed by fluorescent microscopical analysis. The effect of AgNPs on the ultrastructure of bacterial pathogen was evaluated by Transmission electron microscopy.

Management of Intracranial Ventriculitis caused by Multidrug Resistant Acinetobacter Baumannii: Case Report and Literature Review

Background: We report a case of a male patient in our hospital who developed associated multidrug-resistant Acinetobacter baumanii (MDRAB) intracrainial ventriculitis and treated using intraventricular (IVT) plus intrathecal (IT) colistin.
 Objective: The purpose of our case report is to show case the effectiveness and safety of using intraventricular (IVT) plus intrathecal(IT) colistin in the management of potentially fatal MDRAB associated intracrainial ventriculitis.
 Materials and methods: Patient was diagnosed with MDRAB after developing associated symptoms and conducting cerebral spinal fluid (CSF) culture and sensitivity analysis. Colistin 250,000 IU once daily administered via intraventricular plus intrathecal routes for 14 days was prescribed.
 Result: Cerebrospinal fluid was collected on the 14th day post commencement of colistin and sterilization was attained.
 Conclusion: Colistin is a potentially effective and safe therapy for the treatment of MDRAB intracrainial ventriculitis.

Management of intracranial ventriculitis caused by multidrug resistant Acinetobacter baumannii : case report and literature review

Background: We report a case of a male patient in our hospital who developed associated multidrug-resistant Acinetobacter baumanii (MDRAB) intracrainial ventriculitis and treated using intraventricular (IVT)plus intrathecal(IT) colistin. Objective: The purpose of our case report is to show case the effectiveness and safety of using intraventricular (IVT) plus intrathecal(IT) colistin in the management of potentially fatal MDRAB associated intracrainial ventriculitis. Materials and methods: Patient was diagnosed with MDRAB after developing associated symptoms and conducting cerebral spinal fluid(CSF) culture and sensitivity analysis. Colistin 250,000 IU once daily administered via intraventricular plus intrathecal routes for 14 days was prescribed. Result: Cerebrospinal fluid was collected on the 14th day post commencement of colistin and sterilization was attained. Conclusion: Colistin is a potentially effective and safe therapy for the treatment of MDRAB intracrainial ventriculitis. Keywords: Acinetobacter baumannii , colistin, ventriculitis, intraventricular, intrathecal

Antimicrobial Susceptibility Pattern and Prevalence of Extended-Spectrum β-Lactamase Genotypes among Clinical Isolates of Acinetobacter baumanii in Tabriz, North-West of Iran

Background: Multidrug resistant (MDR) Acinetobacter baumanii strains have emerged as novel nosocomial pathogens threatening patients’ lives, especially in intensive-care units (ICU). Various types of extended-spectrum β-lactamases (ESBLs) are involved in conferring resistance to β-lactam antibiotics, making their genotypic characterization an essential prerequisite to take proper preventative measures. Objectives: The aim of this study was to determine the antimicrobial susceptibility and prevalence of blaTEM, blaSHV, blaCTX-M, blaOXA-2, and blaOXA-10 genes among A. baumanii isolates obtained from patients in Tabriz city, North-west Iran. Methods: The clinical isolates of A. baumanii were collected from patients hospitalized in the Imam Reza hospital of Tabriz. Antimicrobial susceptibility patterns were determined by the disk diffusion method. The frequency of different ESBLS resistance genes were determined by PCR. Results: Antimicrobial susceptibility testing through the disk diffusion method revealed that the lowest resistance rates were against polymyxin B (16%), colistin (23%), and rifampin (27%); whereas the highest resistance rate was observed against ticarcillin (100%), cefixime (100%), and ceftizoxim (100%). Screening by double disk synergy test showed that 60% of the isolates were ESBL producers. PCR technique on ESBL-positive isolates determined blaSHV gene as the most prevalent (31.6%) and blaOXA-10 as the least prevalent (8.3%) among the studied resistance genes. Conclusions: The high prevalence of resistance genes supported the essential role of ESBLs in antibiotic resistance of A. baumanii.

Synthesis and biological evaluation of indole core-based derivatives with potent antibacterial activity against resistant bacterial pathogens

The emergence of drug resistance in bacterial pathogens is a growing clinical problem that poses difficult challenges in patient management. To exacerbate this problem, there is currently a serious lack of antibacterial agents that are designed to target extremely drug-resistant bacterial strains. Here we describe the design, synthesis and antibacterial testing of a series of 40 novel indole core derivatives, which are predicated by molecular modeling to be potential glycosyltransferase inhibitors. Twenty of these derivatives were found to show in vitro inhibition of Gram-positive bacteria, including methicillin-resistant Staphylococcus aureus. Four of these strains showed additional activity against Gram-negative bacteria, including extended-spectrum beta-lactamase producing Enterobacteriaceae, imipenem-resistant Klebsiella pneumoniae and multidrug-resistant Acinetobacter baumanii, and against Mycobacterium tuberculosis H37Ra. These four compounds are candidates for developing into broad-spectrum anti-infective agents.

Cathelicidin antimicrobial peptide from Alligator mississippiensis has antibacterial activity against multi-drug resistant Acinetobacter baumanii and Klebsiella pneumoniae

Alligator mississippiensis (American alligator), a member of order Crocodilia, lives in bacteria-laden environments but is not often known to succumb to bacterial infections. Their serum has been shown to have antibacterial activity beyond that of human serum, and it is believed that this activity is partially due to cationic antimicrobial peptides (CAMPs). CAMPs are produced by many organisms as part of the innate immune system. CAMPs are attractive possible therapies against multi-drug resistant bacteria, such as those found in biofilm-infected war wounds, because they seldom cause genetic resistance in bacteria and are effective against antibiotic resistant bacteria. In this work, we identified, synthesized, and characterized a cathelicidin and two shorter fragments from the American alligator. We discovered the cathelicidin using Basic Local Alignment Search Tool (BLAST) alignment and by comparing A. mississippiensis expressed sequence tags (ESTs) with propeptide cathelicidins of other reptiles. We analyzed the structure using bioinformatics tools and circular dichroism and predicted that the full-length cathelicidin peptide has a mixed structure, with an N-terminal α-helix and a center Pro hinge. In minimal inhibitory concentration (MIC) assays, it was determined that the cathelicidin and the two shorter fragments have strong activity against multiple Gram-negative bacteria, including clinical isolates of multi-drug resistant (MDR) Acinetobacter baumannii and carbapenem-resistant Klebsiella pneumoniae. Using the ethidium bromide uptake assay, it was found that these peptides permeabilize the bacterial membrane and are less sensitive to salt inhibition than many other known CAMPs. The alligator cathelicidin peptides were not hemolytic against sheep red blood cells at 300 μg/ml and were not significantly cytotoxic against A549 human lung epithelial cells after 24 h exposure in 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. These alligator cathelicidin peptides have activity similar to other CAMPs from reptiles such as NA-CATH. It is possible that the alligator cathelicidins play an important role in the innate immune response of A. mississippiensis, similar to LL-37 in humans. In addition, due to their activities against MDR bacteria and lack of cytotoxicity, the AM-CATH peptides could be an attractive platform for further development as a potential therapeutic.

Implementation of WHO multimodal hand hygiene (HH) improvement strategy to reduce healthcare-associated infections (HAI) and VAP (ventilator-associated pneumonia) caused by multi-drug resistant acinetobacter baumanii (MDRAB) at Siloam Hospitals Surabaya (SHBS), Indonesia

SHSB is a 160 bed private hospital in Surabaya, Indonesia. The average length of stay (ALOS) is 9.52 d. In 2010, HAI rates at SHSB were high (3.12%) and HH compliance among healthcare workers (HCW) was low (73.34%). At the same time, SHSB had MDRAB outbreak among ICU patients with VAP rate of 10.99/device-days. Therefore, there was a need for quality improvement to reduce HAI and VAP caused by MDRAB.

Antibacterial activities of isothiocyanates extracted from horseradish (Armoracia rusticana) root against Antibiotic-resistant bacteria

The antibacterial activities of isothiocyanates (ITCs) extracted from horseradish root was determined against 4 strains of antibiotic-resistant bacteria, methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant S. aureus (VRSA), multidrug-resistant Acinetobacter baumanii (MRAB), and multidrug-resistant Pseudomonas aeruginosa (MRPA), and 3 strains of normal pathogenic bacteria, S. aureus, A. baumanii, and P. aeruginosa. The minimum bactericidal concentrations (MBC) of ITCs against MRSA, VRSA, MRAB, and MRPA were 666.7, 666.7, 333.3, and 208.3 μg/mL, respectively, and against S. aureus, A. baumanii, and P. aeruginosa were 833.3, 41.7, and 52.1 μg/mL, respectively. ITCs extracted from horseradish root showed the strongest antibacterial activity against A. baumanii with a MBC of 41.7 μg/mL. Among antibiotic-resistant bacteria, ITCs showed the strongest antibacterial activity against MRPA with a MBC of 208.3 μg/mL. MBC values of vancomycin against MRSA, VRSA, and S. aureus were 1,667.7, 2,000.0, and 1,333.3 μg/mL, levofloxacin against MRAB and A. baumanii were 833.3 and 1,333.3 μg/mL, respectively, norfloxacin against MRPA and P. aeruginosa were 666.7 and 7.8 μg/mL, respectively. ITCs showed stronger antibacterial activities than antibiotics against tested bacteria except P. aeruginosa. These results indicate that ITCs extracted from horseradish root should be candidates for antibacterial agent against antibiotic-resistant bacteria.

Increasing hand hygiene compliance to reduce the incidence of multidrug resistant acinetobacter baumanii in ventilator associated pneumonia in ICU Siloam Hospitals Surabaya

Increasing hand hygiene compliance to reduce the incidence of multidrug resistant acinetobacter baumanii in ventilator associated pneumonia in ICU Siloam Hospitals Surabaya