Phenotypic and molecular characterization of Klebsiella pneumoniae in neonates and pediatric patients: antibiotic resistance, β-Lactamase genes, and sociodemographic risk factors.

BACKGROUND: Neonates, infants, and pediatric patients are usually prone to Klebsiella pneumoniae infections. Antimicrobial resistance is a major cause and needs effective surveillance because of the emergence of multidrug-resistant (MDR) and extensively drug-resistant (XDR) strains. The current study was conducted to evaluate K. pneumoniae prevalence, antimicrobial resistance patterns, and detect β-Lactamase and carbapenemase genes among clinical samples from selected major cities of Khyber Pakhtunkhwa (KP), Pakistan. METHODS: Clinical samples (2100) from hospitalized patients were collected at different selected tertiary care and district-level hospitals of Khyber Pakhtunkhwa (KP), Pakistan. Antibiotic susceptibility testing and phenotypic assays were performed for the determination of resistance profiles and detection of ESBL and carbapenemase. Further molecular characterization was performed by PCR of ESBL and carbapenemase genes. An analysis of clinical and sociodemographic data of neonates, infants, and pediatric patients was conducted for the identification of potential major risk factors contributing to K. pneumoniae infections. RESULTS: The overall prevalence of K. pneumoniae among neonates, infants, and pediatric patients across hospitals in Khyber Pakhtunkhwa was 17.6% (371/2100). Blood was the most frequent infection source (10%), followed by urine (3.3%) and sputum (2.2%). The highest prevalence occurred in neonates (22%), compared to infants (15.9%) and pediatric patients (14.9%). Among the isolates, MDR-ESBL phenotypes were 29%, MDR-carbapenemase were 22.6%, and XDR (6.1%). The highest susceptibility was to amikacin (91% in non-MDR, 42% in MDR, and 26% in XDR isolates. Molecular analysis revealed blaCTX-M-14 (17.2%) and blaSHV (15.6%) as the most prevalent ESBL genes, and blaOXA-48 (5.1%) as the predominant carbapenemase gene. Significant risk factors included neonatal age (AOR: 2.10, 95% CI: 1.05–4.23, p = 0.033), prior antibiotic use (AOR: 2.95, 95% CI: 1.87–4.68, p = 0.0002), and hospital stay ≥7 days (AOR: 2.00, 95% CI: 1.35–3.03, p = 0.002). Breastfeeding had a protective effect, significantly reducing infection risk (OR: 0.50; 95% CI: 0.28–0.89; p = 0.022). CONCLUSION: The rising prevalence of MDR and XDR K. pneumoniae poses a critical threat to neonatal and pediatric care in Khyber Pakhtunkhwa. Strengthening antibiotic stewardship, enforcing strict infection control practices in pediatric units, and integrating continuous surveillance into public health policy are essential to curb the spread of resistant strains.