SUMMARY
Objective. To determine the level of surfactant associated protein D (SP-D) in the blood and tracheobronchial lavage (TBL) of premature infants (PI) with respiratory failure (RF). Materials and methods. The study involved 20 children without respiratory distress (control group — I), 80 very low birth weight infants with respiratory distress [IIa — subgroup with respiratory distress syndrome (RDS), IIb — pneumonia], 42 extremely low birth weight infants (IIIa — RDS and IIIb — pneumonia subgroups). The mean gestational age of PI was 29.83±2.37, min. 23, max. 32, birth weight 1202.42±254.96 g, min. 500 g, max. Blood serum (all children) and TBL (only those on invasive ventilation) were collected from infants and SP-D levels were determined using the Human SP-D ELISA Kit from Sun Red Bio (China), statistics were analyzed using the SPSS 20 package. Results. The SP-D level in the early neonatal period in group I was 22.9±12.46 ng/ml. In group IIb, SP-D was 244.41±236.55 ng/ml, 10.6 times higher than in group I (p<0.001), among the subgroups of group II 244.41±236.55 ng/ml in IIb and 65.18±120.35 ng/ml in IIa, the difference was 3.7 times (p<0.01), among the subgroups of group III it was 1.7 times higher in group IIIb (198.82±254.47 ng/ml) compared to group IIIa (117.87±190.62 ng/ml). In 17 patients on respiratory support with invasive ventilation, SP-D was detected in the TBL aspirate at a concentration of 116.58±38.64 ng/ml in subgroup IIIa, which is 2 times higher than in subgroup IIa – 56.50±17.67 ng/ml. Conclusion. Compared to patients with RDS, the increased levels of SP-D in the blood and TBL of patients with pneumonia, and the significantly increased dynamic levels of SP-D in the blood serum of deceased children are considered differential diagnostic and prognostic criteria in respiratory diseases.
Keywords: respiratory distress syndrome, premature infants, surfactant associated proteins, SP-D

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