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Multidrug-Resistant, Potentially Pathogenic Bacteria in Mother's Milk, and Neonatal Oral and Rectal Swabs of Preterm
Sourabh Dutta1, Anwesha Chakraborty1, Manisha Biswal2
1Department of Pediatrics, Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh, 160012 India.
Abstract:
Preterm mother-neonate dyads are often exposed to broad-spectrum antibiotics. We studied preterm dyads for multidrug-resistant potentially pathogenic bacteria (MDR-PPB).To determine colonisation rates of MDR-PPB in mother's milk and neonatal oral and rectal swabs and identify genetically identical strains across the 3 samples. We enrolled lactating mother-neonate dyads, and cultured milk and neonatal oral, rectal swabs under aseptic conditions. We identified bacteria using MALDI-TOF, focusing on a panel of 13 neonatal pathogens of interest. Sensitivity was tested using Vitek2. If the milk, oral, and rectal swab samples from a mother-neonate dyad showed the same species and antibiogram, multi-locus sequence type (MLST) was performed. Of 130 dyads screened, we enrolled 100. 14 milk samples (from 14 mothers) had pathogens of interest, including 9 (64%) MDR bacteria. 82 isolates were grown from the oral swabs (77 neonates), of which 58 (70.7%) were MDR. 130 isolates were grown from the rectal swabs (96 neonates), of which 104 (80%) were MDR. Two mother-neonate dyads had MDR Escherichia coli and Klebsiella pneumoniae species cultured from all three samples with identical antibiograms. On MLST, DNA sequencing analysis of the PCR products showed no variation at all 7 loci of E. coli (Sequence Type-405), whereas, with K. pneumoniae, variations were observed in 4 loci (infB, mdh, phoE,rpoB). An alarming proportion of preterm mother's milk, oral swab and rectal swabs have MDR-PPB. MLST suggested that a pathogenic strain of E. coli was transmitted from mother's milk to the neonate's gut.
Insights
Multidrug-resistant bacteria colonize preterm infants and mothers. Pathogenic E. coli strains were transmitted from mother's milk to neonates, highlighting risks in preterm care.
Area of Science:
- Neonatal Medicine
- Microbiology
- Infectious Diseases
Background:
- Preterm infants are vulnerable to infections.
- Broad-spectrum antibiotic exposure is common in preterm dyads.
- Colonization by multidrug-resistant potentially pathogenic bacteria (MDR-PPB) is a significant concern.
Purpose of the Study:
- To determine MDR-PPB colonization rates in mother's milk and neonatal oral/rectal swabs.
- To identify genetically identical MDR-PPB strains across these sample types.
- To investigate potential transmission routes within mother-neonate dyads.
Main Methods:
- Cultured milk, oral, and rectal swabs from 100 preterm mother-neonate dyads.
- Identified bacteria using MALDI-TOF, focusing on 13 neonatal pathogens.
- Performed antimicrobial sensitivity testing (Vitek2) and multi-locus sequence typing (MLST) for identical strains.
Main Results:
- High MDR-PPB colonization rates observed: 64% in milk, 70.7% in oral swabs, 80% in rectal swabs.
- Identical MDR Escherichia coli (ST-405) strains found in milk, oral, and rectal samples from two dyads.
- Identical MDR Klebsiella pneumoniae strains found across all three sample types in two dyads, with MLST showing variations.
Conclusions:
- Preterm mother's milk and neonates exhibit high rates of MDR-PPB colonization.
- Evidence suggests mother's milk can be a source for neonatal gut colonization by specific MDR pathogens like E. coli.
- Findings underscore the need for strategies to mitigate MDR-PPB transmission in preterm infant care.
