The thought of undergoing an endoscopy or radiographic imaging may deter some individuals with symptoms of irritable bowl syndrome (IBS) from determining if they have inflammatory bowel disease (IBD). The procedures can be invasive and costly, and an alternative method of diagnosis may be ideal.

An alternative may exist in the form of the diagnostic biomarker fecal lactoferrin, which was recently investigated by a group of researchers at the Second Affiliated Hospital of Zhejiang University, School of Medicine, in China. Led by principal investigator Dr. Wen-sheng Pan and lead author Xing-lu Zhou, the team published their findings in the journal BMC Gastroenterology.

The team conducted a meta-analysis of 1,012 patients studied within seven different original research articles to identify the utility of fecal lactoferrin as a biomarker in discriminating IBD from IBS. Multiple patient types, spanning from pediatric to elderly populations, were used to assess the rates of true-positive, false-positive, true-negative, and false-negative diagnoses for IBD.

Using fecal lactoferrin as a biomarker resulted in a sensitivity (true-positive rate) of 0.78 and a specificity (true-negative rate) of 0.94. There was a positive likelihood ratio of 12.31, a negative likelihood of 0.23, and a diagnostic odds ratio of 52.65. Area under the curve was 0.94.

Ultimately, it was determined fecal lactoferrin is a reliable diagnostic for IBD versus IBS. Distinguishing between the two is important because, although the diseases sound similar, the pathophysiology and course of treatment for each disease is unique. According to the article, IBD encompasses a number of idiopathic, chronic, and inflammatory intestinal conditions, while IBS presents without inflammation. IBD requires life-long medical care and can result in significant morbidity, and IBS has a more positive prognosis.

Lactoferrin is a part of the innate immune system and has antimicrobial activity as a bactericide and fungicide. It is released by dying neutrophils, which are present within the mucosa of the bowel during inflammation. This releases lactoferrin into feces, allowing fecal lactoferrin to be evaluated as a biomarker in the clinic.