Related Experiment Videos
Reduction of mucoid Staphylococcus epidermidis adherence to intraocular lenses by selected antimicrobial agents
A A Kadry1, A Tawfik, A A Abu El-Asrar
1Department of Microbiology, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia.
Abstract:
The effect of low concentrations of various antimicrobial agents on the adherence of mucoid Staphylococcus epidermidis to intraocular lenses was investigated. Adherent growth of S. epidermidis on to polymethylmethacrylate lenses was greatly diminished by ciprofloxacin and clindamycin (>75%), followed by ceftazidime ( approximately 50%) and less affected by gentamicin and vancomycin (<25%) compared to the adherent growth of control untreated cells. The reduction in adherence growth was concentration-dependent and found to be due to the inhibition of slime production since no growth inhibition was observed at the concentrations used. Cell surface hydrophobicity was markedly reduced in parallel to the inhibition of adherence as compared to the control cells. The differential effect of antibiotics on adherence, regardless of their antimicrobial activity, may have a clinical significance in reducing the incidence of postoperative endophthalmitis and intraocular inflammation due to the reduction of cell adherence.
Insights
Low concentrations of certain antibiotics significantly reduce Staphylococcus epidermidis adherence to intraocular lenses by inhibiting slime production, not bacterial growth. This may help prevent post-surgical eye infections.
Area of Science:
- Ophthalmology
- Microbiology
- Biomaterials Science
Background:
- Staphylococcus epidermidis is a common cause of intraocular lens (IOL) infections.
- Bacterial adherence to IOLs contributes to biofilm formation and endophthalmitis.
- Understanding factors influencing adherence is crucial for preventing post-operative complications.
Purpose of the Study:
- To investigate the effect of low-concentration antimicrobial agents on mucoid Staphylococcus epidermidis adherence to polymethylmethacrylate (PMMA) IOLs.
- To determine if adherence inhibition is related to antimicrobial activity or other mechanisms.
- To assess the potential clinical significance of these findings.
Main Methods:
- Mucoid Staphylococcus epidermidis strains were cultured and allowed to adhere to PMMA IOLs.
- IOLs were exposed to low concentrations of ciprofloxacin, clindamycin, ceftazidime, gentamicin, and vancomycin.
- Adherent bacterial growth was quantified and compared to untreated controls.
- Slime production and cell surface hydrophobicity were assessed.
Main Results:
- Ciprofloxacin and clindamycin significantly reduced S. epidermidis adherence (>75%).
- Ceftazidime showed moderate reduction (approx. 50%), while gentamicin and vancomycin had minimal effect (<25%).
- Adherence reduction was concentration-dependent and linked to inhibited slime production, not growth inhibition.
- Cell surface hydrophobicity decreased in parallel with reduced adherence.
Conclusions:
- Certain antibiotics, at low concentrations, can inhibit Staphylococcus epidermidis slime production and adherence to IOLs.
- This effect is independent of direct antimicrobial activity.
- Reducing bacterial adherence may be a strategy to decrease the incidence of postoperative endophthalmitis.