Prevalence of multidrug-resistant strains in device associated nosocomial infection and their in vitro killing by nanocomposites

BACKGROUND: As per WHO, global burden of healthcare-associated infections (HAIs) ranges between 7% and 12%. There is a dire need to screen Device associated nosocomial infections (DANIs) in hospitals(1). To investigate the prevalence of microbes in hospitals in DANI cases and analyse in vitro control of multi-drug resistant strains by nanotechnology intervention. METHODS: Patients diagnosed with DANI were enrolled and monitored. Identification and antibiotic susceptibility pattern of the etiological agent of DANIs were made by the phenotypic method and Vitek 2 automated systems according to standard protocol. In addition, biosynthesized nanocomposite was analysed for their antimicrobial activity by agar well-diffusion method, CFU count and DNA degradation analysis. RESULTS: There were a total of 324 patients diagnosed with DANIs. Total 369 microbial pathogens were isolated from DANI patients. The majority (87%) of the pathogenic microbes were gram-negative bacilli and all were multidrug-resistant. 41.5% of the gram-negative isolates were ESBL producers. Methicillin-resistant Staphylococcus aureus contributes about 7.3% of the total isolates in gram-positive bacteria. Nanocomposite showed 100% bactericidal activity at 5 mg/ml concentration within 3 h of incubation, whereas 2.5 mg/ml concentration of nanocomposites takes 6 h to inhibit complete growth. CONCLUSIONS: DANI, which was found in patients of all age groups, us due to multidrug-resistant gram-negative bacteria. The most commn causative agents were Acinetobacter baumannii and Citrobacter species. Nanocomposites can provide an alternative solution to prevent the DANIs.