Risk factors for wound infection caused by Methicillin Resistant Staphylococcus aureus among hospitalized patients: a case control study from a tertiary care hospital in India

Study on Time Distribution and Pathogenic Bacteria of Infection After Auricular Reconstruction With Tissue Expansion for Microtia

BACKGROUND

Postoperative infection is one of the main complications that affect the surgical effect of auricular reconstruction with tissue expansion. Understanding the susceptible time and distribution of pathogens is especially important for the treatment.

METHOD

The data of patients with infection after auricular reconstruction with tissue expansion from September 1, 2018 to August 30, 2024 were collected retrospectively. The microbe species identification results, diagnosis time of infection, surgical methods, and kinds of pathogenic bacteria were analyzed. Statistical methods were used to analyze and calculate the difference in infection time and the distribution of pathogenic bacteria.

RESULT

From September 1, 2018 to August 30, 2024, 237 cases of infection after auricle reconstruction with tissue expansion were diagnosed, and 252 strains of 18 kinds of pathogenic bacteria were detected. Among them, S. aureus (85 strains, 33.73%) and S. epidermidis (40 strains, 15.87%) were the 2 main pathogens. Postoperative infection mainly occurred in the first stage (72 cases, 30.38%) and the second stage (98 cases, 41.35%). The MRSA infection rate in the second stage (24.46%) was significantly higher than that in the other stages. The infection rate was significantly higher in winter (from November to January) (P<0.05). There was no significant difference among other seasons (P>0.05).

CONCLUSION

The main pathogen of infection after ear reconstruction with tissue expansion is Staphylococcus aureus, and winter is the peak period of infection. There are some differences in infection rate and distribution of pathogenic bacteria in different stages of surgery.

Staphylococcus aureus associated with surgical site infections in Western Kenya reveals genomic hotspots for pathogen evolution

Objectives. Staphylococcus aureus is one of the most common pathogens attributed to hospital infections. Although S. aureus infections have been well studied in developed countries, far less is known about the biology of the pathogen in sub-Saharan Africa. Methods. Here, we report on the isolation, antibiotic resistance profiling, whole genome sequencing, and genome comparison of six multi-drug resistant isolates of S. aureus obtained from a referral hospital in Kakamega, Western Kenya. Results. Five of the six isolates contained a 20.7 kb circular plasmid carrying blaZ (associated with resistance to β-lactam antibiotics). These five strains all belonged to the same sequence type, ST152. Despite the similarity of the plasmid in these isolates, whole genome sequencing revealed that the strains differed, depending on whether they were associated with hospital-acquired or community-acquired infections. Conclusion. The intriguing finding is that the hospital-acquired and the community-acquired isolates of S. aureus belonging to the same genotype, ST152, formed two separate sub-clusters in the phylogenetic tree and differed by the repertoire of accessory virulence genes. These data suggest ongoing adaptive evolution and significant genomic plasticity.

Healing wounds, defeating biofilms: Lactiplantibacillus plantarum in tackling MRSA infections

Introduction

Methicillin-resistant Staphylococcus aureus (MRSA) infections are well-known hospital-borne infections and are a major contributing factor to global health concerns of antimicrobial resistance due to the formation of biofilms. Probiotics are known to assist in the healing of wounds through immunomodulation and also possess anti-pathogen properties via competitive inhibition. The probiotic bacterium, Lactiplantibacillus plantarum MTCC 2621 and its cell-free supernatant (Lp2621) have previously been reported to have antibacterial, excellent antioxidant, and wound healing activity in in vitro conditions and wounds contaminated with S. aureus in mice.

Methods

In the current study, we evaluated its anti-MRSA, biofilm inhibition and eradication efficacy, immunomodulatory activity in THP-1 cells, and wound healing potential in wounds contaminated with MRSA infection in mice.

Results

In agar well diffusion assay, Lp2621 showed anti-MRSA activity and revealed dose-dependent inhibition and eradication of biofilm by crystal violet assay as well as by Confocal Scanning Laser Microscopy (CLSM) analysis. Further, Lp2621 showed immunomodulatory activity at varied concentrations as measured by IL-6 and IL-10 gene expression in THP-1 cells. Similar findings were observed in serum samples of mice after treatment of excision wound contaminated with MRSA infection by Lp2621 gel, as evident by expression of IL-6 (pro-inflammatory) and IL-10 (anti-inflammatory) cytokines.

Conclusions

Overall, our results show that Lp2621 has potent anti-MRSA and antioxidant properties and can prevent and eliminate biofilm formation. It also showed promise when applied to mice with MRSA-infected wounds.

Non communicable diseases persist despite being overshadowed by Covid-19 globally

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