Ceragenins and Ceragenin-Based Core-Shell Nanosystems as New Antibacterial Agents against Gram-Negative Rods Causing Nosocomial Infections.

The growing number of infections caused by multidrug-resistant bacterial strains, limited treatment options, multi-species infections, high toxicity of the antibiotics used, and an increase in treatment costs are major challenges for modern medicine. To remedy this, scientists are looking for new antibiotics and treatment methods that will effectively eradicate bacteria while continually developing different resistance mechanisms. Ceragenins are a new group of antimicrobial agents synthesized based on molecular patterns that define the mechanism of antibacterial action of natural antibacterial peptides and steroid-polyamine conjugates such as squalamine. Since ceragenins have a broad spectrum of antimicrobial activity, with little recorded ability of bacteria to develop a resistance mechanism that can bridge their mechanism of action, there are high hopes that this group of molecules can give rise to a new family of drugs effective against bacteria resistant to currently used antibiotics. Experimental data suggests that core-shell nanosystems, in which ceragenins are presented to bacterial cells on metallic nanoparticles, may increase their antimicrobial potential and reduce their toxicity. However, studies should be conducted, among others, to assess potential long-term cytotoxicity and in vivo studies to confirm their activity and stability in animal models. Here, we summarized the current knowledge on ceragenins and ceragenin-containing nanoantibiotics as potential new tools against emerging Gram-negative rods associated with nosocomial infections.

Changing Trends Of Multidrug Resistant Bacteria: A Six Year Experience From A Tertiary Care Hospital.

BACKGROUND: There is a continuous increase in the number of bacteria showing resistance to various antibiotics, limiting the treatment options for infections. The objective of this study was to assess the trend in resistance pattern of multi drug resistant organisms over a period of 6 years. METHODS: A retrospective study was conducted in Indus Hospital and Health Network, Karachi, Pakistan from January 2014 to December 2019. Multidrug resistant organisms were isolated from various samples and the data of corresponding patients were extracted from electronic medical record. The patients of all age groups and either gender was included. Specimens were inoculated on Sheep Blood Agar, chocolate agar and MacConkey agar. Organisms were identified and antibiotic susceptibility testing was performed according to Clinical Laboratory Standard Institute guidelines. RESULTS: In 34628 cases, 5159 (14.8%) were isolated as MDR organisms. Out of these 44.2% were Gram negative, while 55.7% were Gram-positive bacteria. The highest MDR trend was observed for A. baumannii (0-70%) followed by MRSA (0-64%) P. aeruginosa (0-16%) Enterococcus (0-10%) CRE (2.8-5.8%). CONCLUSIONS: The continuous rising trend of multidrug resistant organisms has been observed during the period of our study. Therefore, there is an imperative need of constant monitoring and firm adherences to infection control strategies to avoid spread of MDR organisms.

Predictive factors for multidrug-resistant gram-negative bacteria among hospitalised patients with complicated urinary tract infections.

Background: Patients with complicated urinary tract infections (cUTIs) frequently receive broad-spectrum antibiotics. We aimed to determine the prevalence and predictive factors of multidrug-resistant gram-negative bacteria in patients with cUTI. Methods: This is a multicenter, retrospective cohort study in south and eastern Europe, Turkey and Israel including consecutive patients with cUTIs hospitalised between January 2013 and December 2014. Multidrug-resistance was defined as non-susceptibility to at least one agent in three or more antimicrobial categories. A mixed-effects logistic regression model was used to determine predictive factors of multidrug-resistant gram-negative bacteria cUTI. Results: From 948 patients and 1074 microbiological isolates, Escherichia coli was the most frequent microorganism (559/1074), showing a 14.5% multidrug-resistance rate. Klebsiella pneumoniae was second (168/1074) and exhibited the highest multidrug-resistance rate (54.2%), followed by Pseudomonas aeruginosa (97/1074) with a 38.1% multidrug-resistance rate. Predictors of multidrug-resistant gram-negative bacteria were male gender (odds ratio [OR], 1.66; 95% confidence interval [CI], 1.20-2.29), acquisition of cUTI in a medical care facility (OR, 2.59; 95%CI, 1.80-3.71), presence of indwelling urinary catheter (OR, 1.44; 95%CI, 0.99-2.10), having had urinary tract infection within the previous year (OR, 1.89; 95%CI, 1.28-2.79) and antibiotic treatment within the previous 30 days (OR, 1.68; 95%CI, 1.13-2.50). Conclusions: The current high rate of multidrug-resistant gram-negative bacteria infections among hospitalised patients with cUTIs in the studied area is alarming. Our predictive model could be useful to avoid inappropriate antibiotic treatment and implement antibiotic stewardship policies that enhance the use of carbapenem-sparing regimens in patients at low risk of multidrug-resistance.