Background: Ulcerative colitis and Crohn's disease are idiopathic inflammatory bowel diseases (IBD). Although some clinical activity indexes are commonly used in IBD, specific and sensitive laboratory markers that correlate with disease activity and associated complication are still lacking. Traditional markers, such as C-reactive protein (CRP), the erythrocyte sedimentation rate (ESR), and the white blood cell (WBC) count, are still the most common markers used
in clinical practice. Procalcitonin (PCT) plays a major role in systemic inflammation and induces a dose-dependent increase in TNFα secretion. Plasma level of PCT increases during bacterial infections and sepsis. There are some data showing that serum PCT level is a useful marker in many inflammatory disorders. Previous findings suggested that inflammatory and infectious disease of the bowel might increase serum PCT levels. Anemia is the most prevalent extra intestinal complication of IBD. Serum iron was previously included in several studies as inflammatory marker of IBD.RDW is a quantitative measurement of anisocytosis. Pro-inflammatory cytokines have been reported to inhibit the maturation of erythrocytes, which is caused by erythropoietin. Thus, inflammation causes immature red blood cells to be released into the peripheral circulation, which may result in anisocytosis. Aim of the work: This study aims to evaluate sensitivity and
specificity of serum procalcitonin, serum iron and red cell distribution width (RDW) as novel biological markers of activity in IBD patients. Patients and methods:60 Patients with confirmed IBD diagnosis (Crohn's and ulcerative colitis) were divided into 2groups (30 remission and 30 exacerbation) classified according to Truelove and Witts index in ulcerative colitis and Harvey Bradshaw index in Crohn's disease. Routine diagnostic investigations, serum Procalcitonin and serum iron level were withdrawn. Serum procalcitonin was done by commercially available ELISA kits. Results: The study showed significant difference between the 2 groups as regards serum iron where median in remission was 52 mcg/dl while in activity was 26 mcg/dl (P value:0.033),also for RDW (P value:0.014) and serum procalcitonin where mean in remission
was 0.62 ng/ml while in activity was 0.98 ng/ml ( P value:0.029). Conclusion: RDW, serum procalcitonin and serum iron in IBD patients need to be included in further studies with larger sample size for the possibility to be used as future laboratory markers for disease activity.