title: Role of the neutrophil in the development of systemic inflammatory response syndrome and sepsis following abdominal aortic surgery.
abstract: BACKGROUND
  There is evidence to suggest that the polymorphonuclear neutrophil (PMN) plays a critical early step in the development of the ischaemia-reperfusion syndrome, the systemic inflammatory response syndrome (SIRS) and sepsis. The PMN receptor CD16 plays an important role in phagocytosis, cell-mediated cytotoxicity and the release of free radicals and proteolytic enzymes. The aim of this study was to determine whether there is any relationship between PMN CD16 expression, phagocytosis and the development of sepsis.
  
  
  METHODS
  Fifty patients who underwent elective infrarenal abdominal aortic aneurysm repair were studied. Venous blood was taken before operation, throughout surgery and for 7 days after operation. CD16 expression was measured, unstimulated and following further stimulation, by means of flow cytometry. Phagocytosis was determined using flow cytometry.
  
  
  RESULTS
  Some 36 patients had an uncomplicated recovery; 14 developed SIRS or sepsis. There was no difference between the two groups with respect to nutritional, co-morbid or technical factors. In the group that developed septic complications after operation, the level of PMN CD16 expression was significantly higher before surgery (mean channel fluorescence (MCF) 30.2 versus 10.4; P < 0.05, Mann-Whitney U test) and throughout the postoperative period. Surgery produced no change in CD16 expression. After operation, stimulation of PMNs in the septic group resulted in a fall in CD16 expression (40.8 versus 20.4 MCF; P < 0.05, Mann-Whitney U test); surgery produced no change in the level of expression in the uncomplicated group.
  
  
  CONCLUSIONS
  This study provides evidence of phenotypic and functional differences in neutrophil behaviour in patients who develop sepsis following aneurysm surgery.
authors.affiliation: Department of Vascular Surgery, St James's University Hospital, Beckett Street, Leeds LS9 7TF, UK. jamesianspark@hotmail.com
authors.forename: J I
authors.initials: JI
authors.lastname: Spark
authors.forename: D J
authors.initials: DJ
authors.lastname: Scott
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D017544:Aortic Aneurysm, Abdominal / Q000276:immunology / Q000601:surgery*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009504:Neutrophils / Q000276:immunology*; D010587:Phagocytosis; D011183:Postoperative Complications / Q000276:immunology*; D017452:Receptors, IgG / Q000276:immunology*; D012307:Risk Factors; D018805:Sepsis / Q000209:etiology* / Q000276:immunology; D018746:Systemic Inflammatory Response Syndrome / Q000209:etiology / Q000276:immunology
chemical_list: D017452:Receptors, IgG