Assessment of inflammatory activity in Crohn's disease

Complaints or symptoms of Crohn's disease can be due either to intestinal inflammation or to anatomical abnormalities such as strictures, fistulas and previous intestinal resection, or to a combination of these factors. Since anti-inflammatory or immunosuppressive drugs are only effective in reducing inflammation, assessment of the presence or absence of active inflammation is of great clinical importance. Several disease activity indices have been developed, but none is able to accurately assess inflammatory activity in Crohn's disease. Furthermore, blood parameters of inflammation, such as ESR, leukocytes, thrombocytes and albumin, are not bowel-specific. In contrast, faecal inflammatory parameters are specific for intestinal inflammation. Preliminary results from our laboratory suggest that measurement of intestinal alpha 1-antitrypsin clearance is a sensitive and bowel-specific indicator of active inflammation in Crohn's disease. This inexpensive, safe and patient-friendly measurement deserves a prominent place, not only in drug trials but also in clinical management of patients with Crohn's disease.