Calprotectin test the new promise

Calprotectin Test


i. Background:

• Various types of organic diseases in the gastrointestinal tract cause damage to the intestinal epithelial lining (mucosa layer). Such damage may vary from increased permeability of the mucosa to inflammation and ulcerations. The bowel content is rich in bacteria and other microorganisms releasing substances which may be toxic or chemotactic, i.e. they stimulate leukocytes, in particular polymorphonuclear neutrophil granulocytes (PMN), to migrate into the gut lumen where they release their contents including antimicrobial substances like calprotectin.
• The assessment of inflammatory activity in the intestinal diseases of Crohn's disease or Ulcerative Colitis can be carried out using a variety of different techniques, from the measurement of conventional non-invasive acute-phase inflammatory markers in blood (e. g. C-reactive protein) to direct assessment by coloscopy with intestinal biopsy. However, most of these techniques have significant limitations.

ii. Significant of Faecal Calprotectin

• Faecal Calprotectin has several characteristics of an ideal test: simple, non-invasive and relatively low cost. These features allow for serial monitoring of the disease as well as success, or failure, of treatment. It is stable in faeces for several days.
• Main applications of the Calprotectin :
 Differential diagnosis between inflammatory bowel disease and irritable bowel syndrome
 Differential diagnosis between active intestinal inflammation and non-inflammatory processes such as fibrous strictures and fistulas
 Monitoring of therapy
 Remission or relapse
 High negative predictive value for inflammatory bowel diseases

• Faecal calprotectin has also been investigated in colorectal cancer. One study suggested that faecal calprotectin has a negative predictive value for colorectal neoplasia of 99%, thus making it especially useful for ruling out colorectal malignancy. In multicentre study of first-degree relatives of patients with colorectal cancer undergoing screening colonoscopy, faecal calprotectin was found to have a sensitivity and specificity of identifying colorectal cancer and adenomatous polyps of approximately 80% and 70% respectively.