Poster (16S165)

Fecal calprotectin a sensitive biomarker in prediction of small bowel Crohn's disease detected by Small bowel capsule endoscopy.

Author(s)

Hamid Yousuf,Roisin Egan, Riona Walsh,Orla O'Dwyer, Pardeep Maheshwari, Umair Aleem, Catriona Gallagher, Prof Deidre McNamara

Department(s)/Institutions

Departemnt of Gastroentrology, AMNCH Tallagh, Dublin 24

Introduction

 Small bowel capsule endoscopy (SBCE) is a useful diagnostic tool for small bowel Crohn's disease (CD), with a higher diagnostic yield than standard radiological techniques. However, the majority of patients undergoing either modality do not have CD. 

Aims/Background

Our aim was to correlate a  FC concentration to the SBCE findings in patients undergoing this examination for suspicion of small bowel CD.

Method

In this prospective study patients with suspected or known CD scheduled to have a SBCE were requested to give a stool sample for fecal calprotectin (FC). On the day of SBCE examination CRP and Harvey Bradshaw index was calculated. SBCE was performed as standard and read by experienced gastroenterologists. A SBCE with a Lewis score of >135 or > 3 significant ulcers was considered positive for CD. FC  was analysed externally and results reported as ug/g stool. The predictive value of a FC > 50 and 100ug/g for CD was calculated and  overall correlation assessed  with pearsons r .

Results

In all 84 patients have been invited to participate and 58(69%) have  FC result available at the time of analysis of which; male = 22 (38%), established CD (n=4), suspected CD (n=50), median age  was 47yrs (range 17 to 75 ), median CRP was 1.55 (range 1 to 28.2) and median FC was 53ug/g (range 19.5 to 774) . In all 48 %(28/58) had a normal FC <50ug/g, and 36% (21/58 ) FC > 90 (median 217;range 102.8 to 774). Overall FC was weakly correlated with SBCE, with pearsons's r of 0.4401. The sensitivity, specificity and positive and negative predictive values for FC cut off's > 50 and > 100ug/g were ; FC >50ug/g 67%, 53%, 31% and 83% and for FC >100ug/g 58%, 71%, 39% and 84.

Conclusions

In our prospective study FC was poorly correlated with SBCE findings in both suspected and known CD patients. This may reflect the lack of colonic disease in the majority of our patients > FC does not appear to be a reliable screening tool for SBCE.