The study investigates the dynamics of antibacterial peptides (ABPs) and other biomarkers (β-defensin (hBD-2), cathelicidin (LL-37), lactoferrin, and calprotectin) in the serum and feces of preterm newborns depending on the severity of their condition and the presence of infectious-inflammatory complications.
64 preterm infants were examined and divided into groups: practically healthy (I), those with perinatal encephalopathy (PE) without infections (II), and those with PE and pneumonia (III). The research demonstrated a significant increase in all studied biomarkers in infants with PE and infectious complications (Group III) compared to practically healthy preterms (Group I) (e.g., calprotectin increased 4.1-fold, β-defensin 3.2-fold, cathelicidin 2.0-fold). This indicates the activation of compensatory mechanisms of innate immunity as the first line of defense in response to infection. The levels of these biomarkers correlated with the severity of the condition, making them valuable diagnostic and prognostic indicators for the early identification of newborns at high risk of infectious complications, particularly pneumonia.