Prevalence Of Antibiotic-resistant Infections Research Articles

596. Anti-Biofilm Activity of Isolated Bacteriophages Targeting Pseudomonas aeruginosa and Staphylococcus aureus

Abstract Background A rise in the prevalence of antibiotic-resistant infections has prompted a search for alternative methods to combat bacteria in the human body. People with cystic fibrosis are especially vulnerable because their lung environment provides a habitable environment for chronic infection, biofilm formation, and antibiotic-resistant mutations. The difficulty associated with finding bacteriophages targeted to a specific infection is one reason the treatment is used relatively infrequently, even when antibiotics have failed. This study aimed to isolate phage species for strains of Pseudomonas aeruginosa and Staphylococcus aureus, the most common causes of chronic infections in patients with cystic fibrosis. Methods Phages targeting multidrug-resistant strains of S. aureus and P. aeruginosa were isolated from samples of fecal matter and soil; stocks were enumerated with the double agar overlay method. The potency of the Pseudomonas-hosted isolates in eradicating biofilms was compared to the efficacy of an antibiotic cocktail and the enzyme cellulase through an in vitro resazurin cell viability assay. Each treatment was performed in sextuplicate. Metabolic reduction of resazurin to resorufin was quantified at 24 and 48 hours of growth using a microplate reader. Results Six phage stocks (four targeting Pseudomonas bacteria [from human & feline fecal matter and from soil], two targeting Staphylococcus [from human & feline fecal matter]) contained bacteriophages at concentrations ranging from 3.9x104 pfu/mL to 2.8x107 pfu/mL. The most effective treatments in the assay were found to be cellulase alone and the three inhibitors together. Conclusion Feline fecal matter is a potential source of Pseudomonas and Staphylococcus bacteriophages. Enzymes were found to be a critical component of biofilm treatment. The isolated bacteriophages were not the most potent treatment alone, but when combined with cellulase and antibiotics, bacterial growth was markedly slowed. Disclosures All Authors: No reported disclosures.

From Pathophysiological Hypotheses to Case-Control Study Design: Resistance from Antibiotic Exposure in Community-Onset Infections.

Antimicrobial resistance is a global public health concern, at least partly due to the misuse of antibiotics. The increasing prevalence of antibiotic-resistant infections in the community has shifted at-risk populations into the general population. Numerous case–control studies attempt to better understand the link between antibiotic use and antibiotic-resistant community-onset infections. We review the designs of such studies, focusing on community-onset bloodstream and urinary tract infections. We highlight their methodological heterogeneity in the key points related to the antibiotic exposure, the population and design. We show the impact of this heterogeneity on study results, through the example of extended-spectrum β-lactamases producing Enterobacteriaceae. Finally, we emphasize the need for the greater standardization of such studies and discuss how the definition of a pathophysiological hypothesis specific to the bacteria–resistance pair studied is an important prerequisite to clarify the design of future studies.

Changing the Rules of TB-Drug Discovery.

The discovery of new drugs with novel targets is paramount to the continued success of tuberculosis (TB) treatment due to the increasing prevalence of antibiotic resistant infections in the TB population. Mycobacterium tuberculosis (Mtb) fumarate hydratase (fumarase) is a highly conserved essential protein that shares an active site with human fumarase, making active site inhibition equally cytotoxic for both bacteria and humans. The recent discovery of a set of new Mtb inhibitory compounds that target Mtb-fumarase by binding to a nonconserved allosteric site is a major advancement, providing further evidence to dispel the antibiotic discovery dogma that conserved proteins do not make good antibiotic targets.

Clinical and economic impact of antibiotic resistance in developing countries: A systematic review and meta-analysis.

IntroductionDespite evidence of the high prevalence of antibiotic resistant infections in developing countries, studies on the clinical and economic impact of antibiotic resistance (ABR) to inform interventions to contain its emergence and spread are limited. The aim of this study was to analyze the published literature on the clinical and economic implications of ABR in developing countries.MethodsA systematic search was carried out in Medline via PubMed and Web of Sciences and included studies published from January 01, 2000 to December 09, 2016. All papers were considered and a quality assessment was performed using the Newcastle-Ottawa quality assessment scale (NOS).ResultsOf 27 033 papers identified, 40 studies met the strict inclusion and exclusion criteria and were finally included in the qualitative and quantitative analysis. Mortality was associated with resistant bacteria, and statistical significance was evident with an odds ratio (OR) 2.828 (95%CI, 2.231–3.584; p = 0.000). ESKAPE pathogens was associated with the highest risk of mortality and with high statistical significance (OR 3.217; 95%CIs; 2.395–4.321; p = 0.001). Eight studies showed that ABR, and especially antibiotic-resistant ESKAPE bacteria significantly increased health care costs.ConclusionABR is associated with a high mortality risk and increased economic costs with ESKAPE pathogens implicated as the main cause of increased mortality. Patients with non-communicable disease co-morbidities were identified as high-risk populations.

An Insight into Antibiotic Resistance to Bacterial Infection in Chronic Liver Disease

End stage liver disease leads to immune dysfunction which predisposes to infection. There has been a rise in antibiotic resistant infections in these patients. There is scanty data f from India or idea regarding the same. The present study was undertaken to determine the type of infection acquired and the prevalence of antibiotic resistant infections in cirrhotic patients at a tertiary referral center in South India. In this retrospective study, all consecutive cirrhotic patients hospitalized between 2011 and 2013 with a microbiologically-documented infection were enrolled. Details of previous admission and antibiotics if received were noted. In culture positive infections, the source of infection (ascites, skin, respiratory tract: sputum/endotracheal tube aspirate, pleural fluid; urine and blood) and microorganisms isolated and their antibiotic susceptibility was noted. A total of 92 patients had 240 culture positive samples in the study period. Majority were Klebseilla followed by Escherichia coli and Enterococcus in nosocomial and health care associated infections. However, Enteroccocus was followed by E. coli and Klebsiella in community acquired infections. The antibiotic sensitivity pattern was analyzed for the major causative organisms such as E. coli, Klebsiella and Enterococcus. Most common resistant strains were extended spectrum beta lactamase producing enterobacteriacae (ESBL) followed by carbapenemase producing Klebsiella and methicillin resistant Staphylococcus aureus. Noscomial infection is the most common type, with Klebsiella and E. coli and there is significant rise in ESBL producing organism.

Invasive pneumococcal disease in two non-vaccinated pediatric cases: pleural empyema and bacteremia

Streptococcus pneumoniae, a gram-positive diplococcus, is the causative agent of invasive pneumococcal diseases (IPDs) characterized by severe infections such as bacteraemia, sepsis and meningitis. S.pneumoniae and IPDs are situated in the focus of the vaccine studies because of being encompassed of a significant burden of disease in the world, severe mortality and morbidities, and location in vaccine-preventable diseases group. Although S.pneumoniae has more than 90 defined serotypes, certain serotypes are often identified as the cause of IPDs. Individuals with comorbid and chronic diseases, primary or secondary immune deficiencies, and <2 years or >65 years of age are at increased risk for IPDs. Currently, a 23-valent polysaccharide vaccine and also 7, 10 and 13 valent pneumococcal conjugated vaccines (PCV) have been produced for pneumococci. Phase studies of protein based vaccines, which will provide protection independent of serotypes, and 15-valent pneumococcal conjugated vaccine are still ongoing. In Turkey, in November 2008 PCV7 and in April 2011 PCV13 have been implemented in the national immunization program. First case of the pneumococcal unvaccinated cases presented in this report was a 6-year-old girl patient with pneumonia and pleural empyema due to S.pneumoniae serotype 1, without any underlying risk factors. The other case is a 52-days-old male patient, who had a history of pneumococcal septicemia in the newborn period and was followed for bacteremia associated S.pneumoniae serotype 12B and diagnosed as complement deficiency on follow-up. S.pneumoniae serotype 1 is within serotypes covered by 10 and 13 valent pneumococcal conjugate vaccines and pneumococcal polysaccharide vaccine that are in use today, and is a highly invasive strain often isolated in pneumococcal lobar pneumonia and empyema. S.pneumoniae serotype 12B is a non-vaccine serotype not included in any of conjugate and polysaccharide vaccines, and usually obtained in respiratory infections and nasopharyngeal carriage studies. The first case of this report was presented because of an IPD with a serotype included in PCV13 implemented in the routine childhood vaccination schedule and to give an idea about pneumococcal strains circulating in the community. The second case was discussed to draw attention for the evaluation of immune deficiencies and other risk factors in recurrent infections with encapsulated bacteria such as pneumococci. Pneumococcal conjugate vaccines contribute the public immunity with the reduction of vaccine-type pneumococcal nasopharyngeal carriage, IPD incidence, and IPD associated morbidity and mortality especially in young children, at the same time cause a decrease in the prevalence of antibiotic-resistant infections. Application of the pneumococcal conjugate vaccines covering the whole society is important, according to all these important results.