PTH-094 Faecal Calprotectin Testing in Primary and Secondary Care – are the Current Manufacturer’S Cut-Off Levels Clinically Useful?

Abstract

Background: Faecal Calprotectin (FC) is a protein complex found in high concentrations in neutrophils and is released within the bowel when inflammation occurs. It can be measured quantitatively using ELISA and is very sensitive and specific in discriminating inflammatory from non-inflammatory pathologies causing diarrhoea. The manufacturer recommends a positive stool FC test (>60 μg/g) to be indicative of inflammation and further investigations (e.g. endoscopy, histology and imaging) and referral to a Gastroenterology clinic is advised. Aims: To determine whether the manufacturer's cut-off levels for referral (>60 μg/g) are clinically useful in making a positive diagnosis in patients presenting with chronic diarrhoea. Methods: We analysed the outcome of 122 FC test results done in primary and secondary care during a 3 month period from October to December 2011 performed on patients who presented with chronic diarrhoea without a pre-existing diagnosis of Inflammatory Bowel Disease (IBD). According to manufacturer's guidance, a FC result of >60 μg/g was considered positive and 60 μg/g is not clinically useful to diagnose an organic bowel pathology and further studies are needed to determine the true cut off value for a higher yield of a positive diagnosis. Cost effectiveness studies are also needed to determine referral cut off values.