Significance of surfactant proteins in respiratory distress syndrome in preterm infants




newborns, respiratory distress syndrome, pneumonia, immune status, surfactant protein A, preterm infants


Respiratory diseases are considered to be widespread pathologies among preterm infants.

The research aim was to determine the level of surfactant protein A (SP-A) in the blood and tracheobronchial lavage of infants with respiratory distress syndrome (RDS) and pneumonia, as well as to study its significance in predicting pathological processes in the lungs.

Materials and methods. The study involved 80 very low birth weight infants with respiratory distress (2a - subgroup RDS, 2b - pneumonia), 42 extremely low birth weight infants (3a - RDS and 3b - pneumonia subgroups), and 20 children without respiratory distress (control group - 1).

Results. The initial examination showed that the level of SP-A in venous blood in the control group was 2.9±2.3 ng/ml, while in the 2b group, it was 21.2 ng/ml, which was 7.1 times higher compared to the control group. In group 2, the difference between 2b (21.2 ng/ml) and 2a (6.01 ng/ml) was determined to be 3.5 times. A direct correlation was observed between the level of SP-A in the blood and the oxygen dependence of patients with RDS (r=0.240, p<0.05). In addition, an increase in the level of the inflammatory marker C-reactive protein (CRP) was observed in these patients over time, and a correlation was found between the level of SP-A in the blood and CRP. When comparing the level of SP-A between deceased and surviving infants, it was found to be that SP-A 2.9 times higher in the blood of deceased patients compared to surviving infants, and conversely, 2.3 times higher in tracheobronchial lavage in surviving infants compared to the deceased patients. Based on the results obtained, the importance of SP-A in the differential diagnosis and prognosis of RDS is emphasized.

The research was carried out in accordance with the principles of the Declaration of Helsinki. The study protocol was approved by the Local Ethics Committee of the institution indicated in the work. The informed consent of the children's parents was obtained for conducting the studies.

No conflict of interests was declared by the authors.


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