Abstract
Background Inflammatory bowel disease (IBD) is affecting patients at increasingly younger ages. Endoscopy (upper/lower) with histopathology remains to be the gold standard for the diagnosis. Biochemical markers, as endoscopy is sort of challenging in children, were more and more evaluated in order to define children with high likelihood of needing such invasive procedure. Fecal calprotectin (FC) is raised in patients with IBD. However, it is also raised in other causes of intestinal inflammation. On top of that Studies evaluating FC during the initial investigation of children with suspected IBD have been limited, especially with regard to their small patient groups.
Objectives We aimed to evaluate the diagnostic accuracy of FCin diagnosing IBD patients in comparison with those who had other (non IBD) GIT stressors. Also to define a level at which FC can be safely relied on to distinguish between both.
Methods Using a retrospective case-control design all podiatric patients (<14 years) who underwent endoscopy in the period between January, 2012 to May 2016 were reviewed. All IBD and non-IBD patients who had a FC measurement available before or within 6 months of endoscopic evaluation were examined and FC results were obtained. FC was measured using the PhiCal Test. SPSS version 23 for windows were used to statistically analyse the results.
Results A total of 138 patients (45 IBD and 93 non-IBD controls) met the inclusion criteria. The median FC at diagnosis for IBD group was 1360 mg/L IQR: (556.5 -4085 mg/L), compared to median FC of 91 mg/L IQR: (34.5–277.5 mg/L) in the control group(P. value = 0.2653).There was no significant difference between different types of IBD (P.value = 0.24).Significant difference was noticed between the 2 groups when FC was taken at levels ≥850 mg/L with sensitivity 66.7% (95% CI: 51.1–80) and specify 87.1(95% CI: 78.6–93.2)
Conclusions This study validates FC as a highly sensitive marker for gut inflammation in general when low cut-off levels are taken. However it is poorly specific for IBD with significant result being only observed at relatively high cut-off values. Thus, FC can safely rule out IBD yet further investigations are needed when FC are above normal.