<abstract xmlns="http://www.w3.org/1999/xhtml">

<sec><h3>Background</h3>
<p>The aim of the study was to compare the phagocytic and bactericidal properties of blood platelets and the plasma bactericidal activity in 66 late preterm (LPN) and 74 full-term newborns (FTN).</p>
</sec>
<sec><h3>Materials/Methods</h3>
<p>Blood samples were collected from the umbilical artery. Bacteria of the Staphylococcus aureus ATCC 6538P were used for the tests.</p>
</sec>
<sec><h3>Results</h3>
<p>Platelet counts in LPN vs FTN were the following: 225 vs 258.5 (×10<sup>3</sup>/μL), p = 0.003. The percentage of phagocytic platelets was the following: Me = 1.1 in LTN vs Me = 1.1 in FTN. The phagocytic index was the following: Me = 1 for both LPN and FTN. The phagocytic properties of platelets increased as the birth weight increased. The bactericidal activity of platelets was the following: Me = 0; (average = 0.7) in LPN vs Me = 0; (average = 0.8) in FTN. The median plasma bactericidal activity in LPN was 41.6 vs 43.8, in FTN, p = 0.027. The bactericidal capacity of plasma increased with increasing fetal age and birth weight of newborns. sP-selectin was: 63.9 ng/ml in LPN vs 71 ng/ml in FTN, p = 0.026. IL-6 in LPN was 3.6 vs 3.9 (pg/ml) in FTN, p = 0.02.</p>
</sec>
<sec><h3>Conclusion</h3>
<p>Late preterm newborns have lower defensive capacity against infection than full-term newborns, due to lower platelets count, lower plasma bactericidal activity and lower sP-selectin concentration, which cooperates with neutrophils, monocytes in fighting against infection. All newborns had similar phagocytic and bactericidal properties of platelets.</p>
</sec>
</abstract>

Background
The aim of the study was to compare the phagocytic and bactericidal properties of blood platelets and the plasma bactericidal activity in 66 late preterm (LPN) and 74 full-term newborns (FTN).

Materials/Methods
Blood samples were collected from the umbilical artery. Bacteria of the Staphylococcus aureus ATCC 6538P were used for the tests.

Results
Platelet counts in LPN vs FTN were the following: 225 vs 258.5 (×103/μL), p = 0.003. The percentage of phagocytic platelets was the following: Me = 1.1 in LTN vs Me = 1.1 in FTN. The phagocytic index was the following: Me = 1 for both LPN and FTN. The phagocytic properties of platelets increased as the birth weight increased. The bactericidal activity of platelets was the following: Me = 0; (average = 0.7) in LPN vs Me = 0; (average = 0.8) in FTN. The median plasma bactericidal activity in LPN was 41.6 vs 43.8, in FTN, p = 0.027. The bactericidal capacity of plasma increased with increasing fetal age and birth weight of newborns. sP-selectin was: 63.9 ng/ml in LPN vs 71 ng/ml in FTN, p = 0.026. IL-6 in LPN was 3.6 vs 3.9 (pg/ml) in FTN, p = 0.02.

Conclusion
Late preterm newborns have lower defensive capacity against infection than full-term newborns, due to lower platelets count, lower plasma bactericidal activity and lower sP-selectin concentration, which cooperates with neutrophils, monocytes in fighting against infection. All newborns had similar phagocytic and bactericidal properties of platelets.

The assessment of phagocytic and bactericidal activity of platelets and plasma bactericidal activity in late preterm newborns<xref ref-type="fn" rid="j_01.3001.0014.6647_fn_001a">*</xref>

Department of Statistics and Medical Informatics

Diagnostics Medical University of Bialystok

Postępy Higieny i Medycyny Doświadczalnej

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

The assessment of phagocytic and bactericidal activity of platelets and plasma bactericidal activity in late preterm newborns

Ocena aktywności fagocytarnej i bakteriobójczej płytek krwi oraz aktywności bakteriobójczej osocza u późnych wcześniaków

Background
The aim of the study was to compare the phagocytic and bactericidal properties of blood platelets and the plasma bactericidal activity in 66 late...

	Study groupLPNN = 66	Control groupFTNN = 74	p
Birth weight (g)	Me = 2450(Q1 = 2000; Q3 = 2600)	Me = 3415(Q1 = 3000; Q3 = 3700)	<0.001***
PLT (×10³/μL)	Me = 225(Q1 = 188; Q3 = 267)	Me = 258.5(Q1 = 222; Q3 = 300)	0.003**
Percentage of phagocytic platelets	Me = 1.1(Q1 = 1; Q3 = 1.2)	Me = 1.1(Q1 = 1; Q3 = 1.2)	NS
Phagocytic index	Me = 1(Q1 = 1; Q3 = 1.1)	Me = 1(Q1 = 1; Q3 = 1.1)	NS
Bactericidal activity of platelets	Me = 0, M = 0.7(Q1 = 0; Q3 = 1.2)	Me = 0, M = 0.8(Q1 = 0; Q3 = 1.6)	NS
Plasma bactericidal activity	Me = 41.6(Q1 = 35,4; Q3 = 45.9)	Me = 43.8(Q1 = 38,3; Q3 = 48.4)	0.027*
sP-selectin concentration (ng/ml)	Me = 63.9(Q1 = 50.8; Q3 = 78)	Me = 71(Q1 = 58.4; Q3 = 83.5)	0.026*
Interleukin 6 concentration (pg/ml)	Me = 3.6(Q1 = 2.9; Q3 = 4.6)	Me = 3.9(Q1 = 3.4; Q3 = 4.9)	0.02*

The assessment of phagocytic and bactericidal activity of platelets and plasma bactericidal activity in late preterm newborns*

Article Category: Original Article

Publié en ligne: 19 janv. 2021

Pages: 18 - 23

Reçu: 20 avr. 2020

Accepté: 22 oct. 2020

DOI: https://doi.org/10.5604/01.3001.0014.6647

Mots clés
platelets, phagocytosis, late preterm newborns, infection

© 2021 Alicja Wasiluk et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Fig. 1

Fig. 2

Comparison of birth weight, PLT and parameters evaluating phagocytic and bactericidal activity of platelets between preterm newborns born near term, between 34 and 36 weeks of pregnancy (study group) and full-term newborns (control group)

The assessment of phagocytic and bactericidal activity of platelets and plasma bactericidal activity in late preterm newborns*

Article Category: Original Article

Publié en ligne: 19 janv. 2021

Pages: 18 - 23

Reçu: 20 avr. 2020

Accepté: 22 oct. 2020

DOI: https://doi.org/10.5604/01.3001.0014.6647

Mots clésplatelets, phagocytosis, late preterm newborns, infection

© 2021 Alicja Wasiluk et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Fig. 1

Fig. 2

Comparison of birth weight, PLT and parameters evaluating phagocytic and bactericidal activity of platelets between preterm newborns born near term, between 34 and 36 weeks of pregnancy (study group) and full-term newborns (control group)

Mots clés
platelets, phagocytosis, late preterm newborns, infection