Laboratory Tests in Crohn’s Disease

Laboratory tests are useful for diagnosing Crohn’s disease, assessing disease activity, identifying complications, and monitoring response to therapy. Their role has been considered limited in the past due to lack of specificity. The introduction of biological therapies in inflammatory bowel disease (IBD) has renewed interest in inflammatory markers, especially C-reactive protein (CRP), given their potential to select responders to these treatments. There are several reasons why laboratory markers have been studied in IBD in the past decades: firstly, to gain an objective measurement of disease activity as symptoms are often subjective; secondly, to avoid invasive (endoscopic) procedures which are often a burden to the patient. An ideal marker should have many qualities. It should be easy and rapid to perform, cheap, and reproducible between patients and laboratories.