Immune mechanisms of respiratory disorders developing in preterm infants

Preterm birth is one of the most urgent problems in neonatology. Every year, about 10% of all children are born before their due date. Successful or failed care over the neonatal period in this category are the main factors of neonatal and infant mortality and disability. High-tech and expensive medical services are required to care for premature infants. Despite technological advances, the increasing amount of scientific knowledge, changing therapeutic approaches, growing skills of clinicians do not provide the desired efficiency, and the results of medical care still are far from success for the extra-premature children. The key issue in transition from intrauterine to extra-uterine life is the time point of external respiration. The main efforts for sustaining the preterm child are aimed at its respiratory protection, since breathing is one of the main vital functions. Therefore, respiratory disorders occupy a special place among the pathologies in premature infants. They include a number of diseases that impair normal course of neonatal period, being characterized by negative consequences, determining the quality of life in premature children as well as their families. In the premature birth of a child, various prenatal factors affect the body, contributing to the morphofunctional immaturity and altered adaptation mechanisms. As a result, such newborns need much more high-tech medical care to successfully adapt to life outside the womb. Despite all the advances in protection of respiratory function in the newborn, the implementation of respiratory support can trigger pathological cascades, which result in a «pathological circle» leading to chronic disease. The main mechanisms of damage are realized through immune-mediated and inflammatory reactions. The underlying pathological events are triggered during the intrauterine period, due to imbalance between pro-and anti-inflammatory mechanisms, thus causing impairment of lung maturation. After birth, the immune system of a premature baby has its own features that are formed ante partum. This condition, arbitrarily referred to as «immaturity immunodeficiency», requires further study for deeper understanding of its mechanisms.