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

Abstract

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.

Keywords: Antibacterial; Antimicrobial-resistant, AMR; Catheter-associated Urinary Tract Infection, CAUTI; Central Line-associated Bloodstream Infection, CLABSI; Device associated nosocomial infection; Device-associated Nosocomial Infections, DANIs; Heathcare associated infections; Intensive Care Unit, ICU; Multi drug resistant; Nanocomposites; Ventilator-associated Pneumonia, VAP.

Fig. 1

(A) MRSA detection by cefoxitin disc diffusion method, (B) Double disc methods for ESBL detection, (C) Metallo β-Lactamase detection by combined disc method.

Fig. 2

Distribution of β-lactamase Producer. EC: Escherichia coli; KS: Klebsiella species; Pr. S: Proteus species; Ps. A: Pseudomonas aeruginosa; AB: Acinetobacter baumannii; CB: Citrobacter species; ESBL: Extended spectrum of β-lactamase; MBL: Metallo β-lactamase.

Fig. 3

Antimicrobial Activity of nanocomposites. Carbon quantum dots decorated dual Z-scheme Manganese Indium Sulphide/Cuprous Oxide/Silver oxide Nanocomposite was incubated with various MDR isolates and CFUs was enumerated at different time intervals (A) 3 h (B) 6 h (C) 24 h. EC: Escherichia coli; KS: Klebsiella species; Pr. S: Proteus species; Ps. A: Pseudomonas species; AB: Acinetobacter baumannii.

Fig. 4

Agarose gel electrophoresis for DNA degradation by 2.5 mg/ml nanocomposite: Lane L (2 kb Ladder), Lane 1 (DNA isolated from untreated MDR Escherichia coli strains), Lane 2–6 (DNA isolated from treated MDR strains of Escherichia coli, Klebsiella species, Proteus species, Pseudomonas aeruginosa and Acinetobacter baumannii).