PCR-Based Screening of Resistance Genes in Multidrug-Resistant Nosocomial Bacterial Isolates from Hospitalized Patients: Implications for Microbiology and Immunology Aspects
| Author | Amin Pouresmail | en |
| Author | Abbasali Dehpour Jouibari | en |
| Issued Date | 2026-04-30 | en |
| Abstract | Background: Healthcare-associated infections represent a major global health threat, particularly in resource-limited settings such as Iran. The rapid emergence of multidrug-resistant pathogens has substantially limited treatment options and underscored the need for molecular surveillance beyond phenotypic testing. Objectives: This study aimed to phenotypically and molecularly characterize bacterial species distribution, antibiotic resistance patterns, and key resistance genes among isolates recovered from hospitalized patients at Shahid Beheshti Hospital in Babol, Iran. Methods: Clinical specimens were aseptically collected from 209 patients, cultured on selective media, and identified by Gram staining, colony morphology assessment, and standard biochemical tests. Antimicrobial susceptibility testing was performed using the Kirby-Bauer disk diffusion method on Mueller-Hinton agar in accordance with Clinical and Laboratory Standards Institute guidelines. Multidrug resistance was defined as resistance to at least 3 antimicrobial classes. Quality-control strains were used throughout susceptibility testing in accordance with Clinical and Laboratory Standards Institute recommendations. The antibiotic disks included ciprofloxacin (5 µg), imipenem (10 µg), ceftazidime (30 µg), cefotaxime (30 µg), gentamicin (10 µg), vancomycin (30 µg), oxacillin (1 µg), and cefoxitin (30 µg). Results: Among 209 patients, Klebsiella spp. predominated (35.4%), followed by Escherichia coli (19.6%) and Pseudomonas aeruginosa (19.1%). PCR screening revealed no blaTEM, blaSHV, or blaKPC bands among the 24 tested Gram-negative isolates, whereas mecA was detected in 3 of 21 Gram-positive isolates (14.3%). Chi-square analysis demonstrated significant associations between bacterial species and antimicrobial resistance patterns (P < 0.05). Conclusions: In this cohort of hospitalized patients, Gram-negative Enterobacteriaceae, predominantly Klebsiella spp. and E. coli, together with P. aeruginosa, were the main nosocomial pathogens, and urinary catheter-associated infections were the predominant clinical entity. PCR-based resistance-gene screening demonstrated the presence of mecA-positive methicillin-resistant Staphylococcus aureus isolates, whereas blaTEM, blaSHV, blaKPC, and vanA genes were not detected in the tested isolates. These findings suggest that additional resistance mechanisms and uninvestigated resistance genes may contribute to the observed phenotypic resistance patterns. | en |
| DOI | https://doi.org/10.5812/jjm-171554 | en |
| URI | https://brieflands.com/journals/jjm/articles/171554 | en |
| Keyword | Microbial Drug Resistance | en |
| Keyword | Methicillin-Resistant Staphylococcus Aureus | en |
| Keyword | Carbapenemases | en |
| Keyword | Beta-Lactam Resistance | en |
| Keyword | PCR | en |
| Publisher | Brieflands | en |
| Title | PCR-Based Screening of Resistance Genes in Multidrug-Resistant Nosocomial Bacterial Isolates from Hospitalized Patients: Implications for Microbiology and Immunology Aspects | en |
| Type | Research Article | en |
Files
Original bundle
1 - 1 of 1
Loading...
- Name:
- jjm-19-4-171554-publish-pdf.pdf
- Size:
- 239.65 KB
- Format:
- Adobe Portable Document Format
- Description:
- Article/s PDF