Neutrophil gelatinase-associated lipocalin in blood in children with inflammatory bowel disease

Abstract

Background: Neutrophil gelatinase-associated lipocalin (NGAL) is a 25 kDa glycoprotein present in the bodily fluids and tissues. It is secreted by neutrophils, epithelial cells, hepatocytes and adipocytes, and its expression is highly increased in response to cellular stress. The role of NGAL in the pathophysiology of inflammatory bowel disease including Crohn's disease and ulcerative colitis in children has thus far not been studied.

Methods: The following groups of children were included: (i) inflammatory bowel disease group, n = 36, aged from 1 to 18 years with Crohn's disease (n = 19) and ulcerative colitis (n = 17); (ii) control group, n = 126; and (iii) disease control group, n = 27, without inflammatory bowel disease, with a food and/or inhalant allergy.

Results: Healthy children aged from 1 to 8 years exhibited lower NGAL level than those of 9 to 18 years old (39.0; 18.1-83.7 ng/mL vs 57.6; 28.7-107 ng/mL, P = 0.001). In the younger, but not in the older children, the serum NGAL level correlated with their age, r = 0.334, P = 0.001. In children with inflammatory bowel disease, serum NGAL level was higher (108; 37.3-245 ng/mL) than in healthy (42.0; 18.1-107 ng/mL) and allergic, noninflammatory bowel disease children (49.3; 19.3-107 ng/mL), P = 0.001. Serum NGAL levels in Crohn's disease and ulcerative colitis children did not correlate with age, gender, disease activity, and indices of the inflammation.

Conclusion: Serum NAGL levels are highly elevated in Crohn's disease and ulcerative colitis in children compared to the healthy control group. Systematic studies are needed to explain the role of this protein in the inflammatory bowel disease.

Keywords: allergy; biomarkers; neutrophil gelatinase-associated lipocalin; pediatric inflammatory bowel disease.