title: Increased intestinal permeability in inflammatory bowel diseases assessed by iohexol test.
abstract: OBJECTIVE
  To study intestinal permeability (IP) and its relationship to the disease activity in patients with inflammatory bowel diseases (IBD) - Crohn's disease (CD) and ulcerative colitis (UC).
  
  
  METHODS
  Fifty-eight patients with active IBD (32 with CD and 26 with UC) and 25 healthy controls consented to participate in the study. The clinical activity of CD was estimated using the Crohn's Disease Activity Index (CDAI), and the endoscopic activity of UC using the Mayo scoring system. IP was assessed by the rise in levels of iohexol, which was administered orally (25 mL, 350 mg/mL) 2 h after breakfast. Three and six hours later serum (SIC mg/L) and urine (UIC g/mol) iohexol concentrations were determined by a validated HPLC-UV technique.
  
  
  RESULTS
  In the CD group, SIC values at 3 h (2.95 ± 2.11 mg/L) and at 6 h after ingestion (2.63 ± 2.18 mg/L) were significantly higher compared to those of healthy subjects (1.25 ± 1.40 mg/L and 1.11 ± 1.10 mg/L, respectively, P < 0.05). UIC (g/mol) values were also higher in patients, but the differences were significant only for UIC at 6 h. Significant positive correlation (P < 0.05) was found between the CDAI and IP, assessed by SIC at 3 h (r = 0.60) and 6 h (r = 0.74) after the ingestion. In comparison to controls, SIC and UIC of UC patients were higher in the two studied periods, but the differences were significant at 6 h only. Significantly higher values of SIC (P < 0.05) were found in patients with severe endoscopic activity of UC compared to those of patients with mild and moderate activity (3.68 ± 3.18 vs 0.92 ± 0.69 mg/L).
  
  
  CONCLUSIONS
  Serum levels of iohexol at 3 h and 6 h after its ingestion reflect increased IP, which is related to the disease activity in patients with IBD.
authors.affiliation: Clinical Center of Gastroenterology, University Hospital Queen Joanna, Medical University, Sofia 1527, Bulgaria. vanger@hotmail.com
authors.forename: Vanya A
authors.initials: VA
authors.lastname: Gerova
authors.forename: Simeon G
authors.initials: SG
authors.lastname: Stoynov
authors.forename: Dimitar S
authors.initials: DS
authors.lastname: Katsarov
authors.forename: Dobrin A
authors.initials: DA
authors.lastname: Svinarov
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000378:metabolism*; D007413:Intestinal Mucosa / Q000378:metabolism*; D007472:Iohexol / Q000493:pharmacokinetics*; D008297:Male; D008875:Middle Aged; D010539:Permeability
chemical_list: D007472:Iohexol