Related Experiment Video
Updated: Sep 13, 2025
Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria
Published on: May 8, 2013
Study of Class 1, 2, and 3 Integrons, Antibiotic Resistance Patterns, and Biofilm Formation in Clinical
Eman E Hegazy1, Wageih Salem ElNaghy1, Marwa M Shalaby1
1Department of Medical Microbiology and Immunology, Faculty of Medicine, Tanta University, Tanta 31527, Egypt.
Abstract:
Antibiotic resistance and biofilm formation complicate Staphylococcus aureus infections, raising concerns for global health. Understanding antimicrobial resistance and biofilm formation in these pathogens is essential for effective infection management. The current research aimed to assess antibiotic resistance patterns, biofilm formation, and the occurrence of integron classes 1, 2, and 3 in clinical S. aureus isolates. The disc diffusion method tested antibiotic susceptibility. MRSA strains were identified by cefoxitin disc diffusion, and the mecA gene by PCR. The D-test also assessed macrolide-lincosamide-streptogramin B. A microtiter plate assay assessed biofilm formation. By PCR, integron classes were examined. Of the 63 S. aureus isolates, 25 were MSSA and 38 were MRSA. Pus (39.5%) was the most prevalent clinical source of MRSA isolates, while blood (24%) was the predominant source of MSSA isolates. MRSA isolates were more resistant to clindamycin, ciprofloxacin, ofloxacin, levofloxacin, tetracycline, and doxycycline than MSSA isolates. In total, 76.2% of the isolates produced biofilm. Biofilm-producing isolates were more resistant to cefoxitin and clindamycin. The isolates had 33.3% cMLSB resistance. The intI1 gene was found in 21 S. aureus isolates (33.3%), whereas the intI2 or intI3 genes were not detected. Our findings demonstrate the need for strict infection control to prevent the spread of resistant bacteria.
Insights
This study found that clinical Staphylococcus aureus isolates, particularly MRSA, exhibit significant antibiotic resistance and biofilm formation. Integron class 1 was detected, highlighting the need for enhanced infection control measures.
Area of Science:
- Microbiology
- Infectious Diseases
- Antimicrobial Resistance
Background:
- Antibiotic resistance and biofilm formation in Staphylococcus aureus are major global health concerns.
- Effective management of S. aureus infections requires understanding these resistance mechanisms.
Purpose of the Study:
- To evaluate antibiotic resistance patterns, biofilm formation, and integron classes 1, 2, and 3 in clinical S. aureus isolates.
- To differentiate resistance profiles between Methicillin-Resistant Staphylococcus aureus (MRSA) and Methicillin-Sensitive Staphylococcus aureus (MSSA).
Main Methods:
- Antibiotic susceptibility testing using disc diffusion and PCR for mecA gene.
- D-test for macrolide-lincosamide-streptogramin B resistance and microtiter plate assay for biofilm formation.
- PCR analysis to detect integron classes 1, 2, and 3.
Main Results:
- Out of 63 isolates, 38 were MRSA and 25 were MSSA. MRSA showed higher resistance to clindamycin, ciprofloxacin, and tetracyclines.
- 76.2% of isolates formed biofilms, with biofilm producers more resistant to cefoxitin and clindamycin.
- Integron class 1 (intI1) gene was present in 33.3% of isolates; intI2 and intI3 were not detected.
Conclusions:
- Clinical S. aureus isolates, especially MRSA, demonstrate significant antibiotic resistance and biofilm-forming capabilities.
- The presence of integron class 1 suggests potential for further resistance gene dissemination.
- Strict infection control is crucial to mitigate the spread of these resistant S. aureus strains.
Related Concept Videos
01:30Development of Antibiotic Resistance
01:29Biofilms
01:28Gene Regulation in Microbial Communities: Quorum Sensing
01:26Healthcare Associated Infections I: Iatrogenic, Exogenic and Endogenic
HAIs significantly increase the cost of health care. Extended stays in healthcare institutions, increased disability, increased costs of medications, including specialized antibiotics, and prolonged recovery times add to the patient's expenses and the healthcare institution and funding bodies.
01:13Special Staining Techniques