Usefulness of laboratory data in estimation of Crohn's disease activity

Crohn's disease (CD) is a chronic inflammatory disease characterized by unpredictable and severe course. Most clinicians use simple laboratory parameters of inflammatory activity such as erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), the number of leukocytes (Le) and platelet count to assess disease activity. The aim of this paper was to determine the value of various laboratory parameters in the assessment of Crohn's disease activity. The study included 36 patients, 15 men and 21 women, treated for Crohn's disease at the Gastroenterohepatology Clinic, Clinical Centre, University of Sarajevo, in period 2006 and 2007. Assessed patients were divided into three groups, according to the degree of disease activity, which was determined using the Crohn's Disease Activity Index (CDAI). Mild disease (MD) was present in 15, moderately severe disease (MSD) in 14, and severe disease (SD) in 7 patients. Statistical significance of association between values of laboratory parameters with the degree of severity of illness was investigated using the 95% Confidence Interval test. CRP showed a statistical significance for the relationship between MD-MSD (95% CI 6,645-74,333) and the relationship between MD-SD (95% CI 4,114-135,278), while the relationship between MSD-SD was not statistically significant. MPV showed statistical significance only for the relationship between MD-MSD (95% CI 0,060-2,909). Sedimentation rate and the number of red blood cells showed statistical significance for the relationship MD-SD (95% CI 10,638-62,943 and 0,077-1,080). Haemoglobin, hematocrit and platelet count showed statistical significance for the relationship between MD-MSD and MD-SD. Number of leukocytes did not show any statistically significant relationship with clinical activity of disease. The most reliable indicators of activity of Crohn's disease in this study were CRP, MPV, haemoglobin, hematocrit and platelet count, while leukocyte number did not correlate with disease activity. Neither parameter was sensitive enough to distinguish the relationship between moderately severe disease and severe disease. Until finding a "gold standard" for assessment of clinical disease activity, various laboratory and other parameters must be combined and compared with other indicators, such as endoscopic findings and radiological results.