Monocyte function-associated antigen expression during and after pediatric cardiac surgery.
OBJECTIVE
Systemic inflammatory response syndrome and infectious complications are major causes of morbidity and mortality after cardiopulmonary bypass. Recent work in adult patients suggests that the balance between proinflammatory and anti-inflammatory mediators is important. We hypothesized that the expression of different function-related receptors on circulating monocytes might reflect the net response of the inflammatory reaction.


METHODS
We performed a prospective and observational study in a tertiary pediatric cardiac center in a population of children (n = 40) undergoing elective cardiac surgery. Expression of receptors on the surface of monocytes was assessed before, during, and after surgical intervention.


RESULTS
Early monocyte activation was demonstrated by changes of the expression of the chemokine receptor CCR2, which was inversely correlated with plasma levels of monocyte chemotactic protein 1 (rho = -0.54, P = .002). High levels of monocyte chemotactic protein 1 were found in children with high expression of the adhesion receptor CD11b/CD18 on circulating monocytes. The intensity of human leukocyte antigen DR expression rapidly decreased in all children after the onset of cardiopulmonary bypass ( P < .001). Low human leukocyte antigen DR expression was correlated with increased plasma levels of interleukin 10 postoperatively. Children who had signs of bacterial pneumonia postoperatively had lower levels of human leukocyte antigen DR expression before surgical intervention (relative risk, 13.3; P = .007).


CONCLUSIONS
The expression of monocyte function-related receptors is altered after cardiac surgery. Early activation of monocytes by monocyte chemotactic protein 1 possibly released from the heart is followed by an anti-inflammatory response with suppression of monocyte human leukocyte antigen DR expression. The increased risk of bacterial infection after pediatric cardiac surgery can be anticipated by surveillance of monocyte function before surgical intervention.
Divisions of Pediatric Intensive Care Medicine, University Children's Hospital of Zurich, Steinwiesstrasse 75, CH-8032 Zurich, Switzerland. peter.gessler@kispi.unizh.ch
Peter
P
Gessler
Rene
R
Pretre
Christoph
C
Bürki
Valentin
V
Rousson
Bernhard
B
Frey
David
D
Nadal
D018845:CD11 Antigens / Q000378:metabolism; D018821:CD18 Antigens / Q000378:metabolism; D006348:Cardiac Surgical Procedures; D002315:Cardiopulmonary Bypass; D018932:Chemokine CCL2 / Q000378:metabolism; D002648:Child; D002675:Child, Preschool; D005434:Flow Cytometry; D006684:HLA-DR Antigens / Q000378:metabolism; D006331:Heart Diseases / Q000453:epidemiology / Q000276:immunology* / Q000601:surgery; D006801:Humans; D007223:Infant; D018950:Lipopolysaccharide Receptors / Q000378:metabolism*; D009000:Monocytes / Q000276:immunology*; D011014:Pneumonia / Q000453:epidemiology; D011446:Prospective Studies
D018845:CD11 Antigens; D018821:CD18 Antigens; D018932:Chemokine CCL2; D006684:HLA-DR Antigens; D018950:Lipopolysaccharide Receptors