Key aspects of neonatal adaptation in preterm newborns of gestational age 32–36 weeks and 6 days, whose intestines are colonized by Klebsiella pneumoniae with uge, fim and kfu genes

Introduction. Modern molecular and genetic studies refute the previous concept of the sterility of the intrauterine environment: it has been established that the fetal gastrointestinal tract already contains microorganisms, including Klebsiella pneumonia (KP), whose colonization is determined by a complex of perinatal factors (gestational age, type of feeding, stay in the intensive care unit, and antibiotic therapy). The outcome of colonization of the intestines of premature infants — from asymptomatic carriage to full-blown infection — is determined by the state of local mucosal protection, the immunological reactivity of the child, and the virulent properties of Klebsiella pneumoniae. The presence of genetically determined virulence factors in KP (genes fim, kfu, uge) and their potential impact on the course of the neonatal period justify the relevance of this study.

Study Objective. To study the key aspects of neonatal adaptation in premature newborns of gestational age 32–36 weeks and 6 days, whose intestines are colonized by Klebsiella pneumoniae with uge, fim, and kfu genes.

Materials and Methods. A survey was conducted on 30 newborns with a gestational age of 32–36 weeks and 6 days, whose intestines were colonized with Klebsiella pneumoniae (KP). Depending on the genovariant of the strains, the children were divided into three groups: Group 1 included premature infants colonized with KP uge (n=6), Group 2 included uge+fim (n=16), and Group 3 included kfu+uge+fim (n=8). A comprehensive assessment of clinical, laboratory, instrumental, and microbiological indicators was conducted in premature infants. Detection of uge, fim, and kfu genes was performed using real-time polymerase chain reaction (PCR).

Results. The article presents data on the course of the neonatal period in 32–36 weeks 6 days of GA children with CR with a different set of genes. It was shown that anthropometric data, the Apgar score, in all groups were comparable. Premature infants with kfu+uge+fim genes had the lowest levels of hemoglobin (113.37±14.82 g/l) and hematocrit (33.73±4.56%) on the 10th–14th day of life (p<0.001), the maximum duration of respiratory support (2.06±1.24 days; p=0.012) and antibacterial therapy (19.0±5.60 days; p=0.005), as well as deterioration with transfer to the ICU in 37.5% of cases. Children with the uge+fim genotype were more likely to have perinatal infections (81.25%; p<0.017) and retained colonization with K. pneumoniae at discharge (100%; p=0.002).

Conclusion. Since premature infants colonized with K. pneumoniae with uge+fim and kfu+uge genotypes remain bacteriologically positive by the time of discharge, the risk of Klebsiella infection persists due to immune immaturity, necessitating their follow-up.

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