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Published on: March 3, 2023
Molecular Characterization of New Delhi Metallo-ß-Lactamases-Producing Bacteria in the Gastrointestinal Tract of
Dipasri Konar1, Naz Perween2, Shyam Kishor Kumar3
1Microbiology, Jan Swasthya Sahyog, Chhatishgarh, IND.
Background:
The emergence of carbapenem-resistance in the gut flora of patients in the intensive care unit (ICU) poses a significant risk for infection with these types of pathogens.
Materials And Methods:
New Delhi metallo-ß-lactamase 1 (NDM-1) in the gut flora of ICU patients was detected in cultures of a single rectal swab from each patient admitted to the ICU for a minimum period of 48 hrs. Samples were processed in the microbiology laboratory using blood agar and MacConkey agar. Identification of pathogens, carbapenem resistance, and metallo-ß-lactamase production was made using standard laboratory procedures. Bacterial isolates were also used for the determination of the NDM-1 gene by molecular methods.
Results:
One hundred twenty-two patients with different clinical presentations were recruited in the study. Two hundred nine bacteria were isolated, with Escherichia coli being the most common isolate. A total of 54/122 (44.3%) patients harbored carbapenem-resistant organisms (CRO), 36/122 (29.5%) carried metallo-β-lactamase-producing organisms (MBLO), and 30/122 (24.6%) carried bacteria with the NDM-1 gene. Patients who harbored CRO and MBLO had longer mean duration of stay in the ICU and hospital than those not harboring CRO and MBLO. All the metallo-β-lactamases were simultaneously resistant to other groups of antibiotics also. Use of invasive devices, three or more classes of antibiotics, hospitalization during the previous six months, comorbidities, and hospital stay for ≥48 hours before ICU admission had a significant association with colonization with CRO.
Conclusion:
Patients admitted in ICU or with serious diseases should be screened for gastrointestinal carriage of carbapenem-resistant organisms. Irrational use of antibiotics must be stopped to prevent the emergence and spread of such organisms.
Insights
Carbapenem-resistant organisms (CRO) are prevalent in ICU patients, with nearly half carrying these dangerous bacteria. Screening and judicious antibiotic use are vital to curb the spread of NDM-1 and other resistant strains.
Area of Science:
- Medical Microbiology
- Infectious Diseases
- Public Health
Background:
- Carbapenem-resistant organisms (CRO) in intensive care unit (ICU) patients pose a significant infection risk.
- Gut flora carriage of these pathogens is a key concern.
Purpose of the Study:
- To detect and characterize carbapenem-resistant organisms (CRO), including those producing New Delhi metallo-β-lactamase 1 (NDM-1), in ICU patients.
- To identify risk factors associated with CRO colonization.
Main Methods:
- Rectal swabs from 122 ICU patients were cultured.
- Standard microbiological techniques and molecular methods identified bacteria, carbapenem resistance, metallo-β-lactamase production, and the NDM-1 gene.
Main Results:
- 44.3% of patients harbored CRO, 29.5% carried metallo-β-lactamase-producing organisms (MBLO), and 24.6% carried NDM-1 positive bacteria.
- CRO and MBLO carriers had longer ICU/hospital stays.
- Factors like invasive devices, broad-spectrum antibiotic use, and prior hospitalization were linked to CRO colonization.
Conclusions:
- Screening ICU patients for gastrointestinal CRO carriage is recommended.
- Preventing the emergence and spread of CRO requires addressing irrational antibiotic use.
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