(Neutrophil gelatinase-associated lipocalin as a marker of disease activity in patients with Inflammatory bowel disease )

Abstract

Inflammatory bowel disease (IBD) is an idiopathic disease caused by a dysregulated immune response to host intestinal microflora. Although the etiology of IBD remains largely unknown, it involves a complex interaction between the genetic, environmental, or microbial factors and the immune responses. The two major types of inflammatory bowel disease are ulcerative colitis (UC), which is limited to the colonic mucosa, and Crohn’s disease (CD), which can affect any segment of the gastrointestinal tract from the mouth to the anus. The diagnosis of IBD is based on a combination of clinical presentation and endoscopic, radiologic, histologic, and pathologic findings. Laboratory testing is complementary in assessing disease severity and complications of disease. There is no single laboratory test that can make an unequivocal diagnosis of IBD. The sequence of testing is dependent on presenting clinical features. The most utilized biomarker for ulcerative colitis and Crohn’s disease is faecal calprotectin, which is useful particularly for diagnosis and follow-up . Neutrophil gelatinase-associated lipocalin (NGAL, also known as lipocalin 2 or siderocalin, gene symbol LCN2) was first discovered in 1996. This 24 kDa glycoprotein is part of the lipocalin superfamily known to bind and transport small hydrophobic molecules. NGAL was originally shown to be a component of specific granules in human neutrophils and has been identified with cell-type-specific expression in several tissues like bronchus, stomach, small intestine, pancreas, kidney, prostate gland and thymus.