title: Increased strength of erythrocyte aggregates in blood of patients with inflammatory bowel disease.
abstract: BACKGROUND
  Increased strength of red blood cell (RBC) aggregates are present during the acute inflammatory response and contribute to erythrocyte aggregation and may lead to microvascular dysfunction. Inflammatory bowel diseases (IBDs) are characterized by damage to the bowel wall. This damage may be at least partially attributed to microvascular ischemia caused by enhanced erythrocyte aggregation. The aim of this study was to evaluate the strength of RBC aggregates in the blood of patients with IBD.
  
  
  METHODS
  The strengths of RBC aggregates were characterized by integrative RBC aggregation parameters, determined by measuring of RBC aggregation as a function of shear stress. The results are represented as the area under the curve (AUC) of aggregate size plotted against shear stress. For each patient, dynamic aggregation and disaggregation of RBC were recorded and analyzed according to the RBC aggregate size distribution at the different shear stresses. Aggregation indices were correlated with disease activity and inflammatory biomarkers.
  
  
  RESULTS
  We examined 53 IBD patients and 63 controls. IBD patients had significantly elevated concentrations of inflammation-sensitive proteins and aggregation parameters. The strength of large aggregates, represented by AUC for large fraction aggregates, among patients (15.2 +/- 18.6) was double that of controls (7 +/- 10.9) (P = 0.006). The strength of large aggregates correlated with disease activity (r = 0.340; P < 0.001) with concentration of fibrinogen (r = 0.575; P < 0.001) and with concentration of high sensitivity C-reactive protein (r = 0.386; P < 0.001).
  
  
  CONCLUSIONS
  The strength of RBC aggregates is increased in patients with IBD and correlates with the intensity of the acute phase response. This could contribute to bowel damage in these diseases.
authors.affiliation: Department of Gastroenterology and Liver Diseases, Tel Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Nitsan
authors.initials: N
authors.lastname: Maharshak
authors.forename: Yaron
authors.initials: Y
authors.lastname: Arbel
authors.forename: Itzhak
authors.initials: I
authors.lastname: Shapira
authors.forename: Shlomo
authors.initials: S
authors.lastname: Berliner
authors.forename: Ronen
authors.initials: R
authors.lastname: Ben-Ami
authors.forename: Saul
authors.initials: S
authors.lastname: Yedgar
authors.forename: Gershon
authors.initials: G
authors.lastname: Barshtein
authors.forename: Iris
authors.initials: I
authors.lastname: Dotan
mesh_terms: D000328:Adult; D019540:Area Under Curve; D015415:Biomarkers / Q000097:blood*; D003093:Colitis, Ulcerative / Q000097:blood*; D004903:Erythrocyte Aggregation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged
chemical_list: D015415:Biomarkers