P364 Faecal calprotectin testing in patients presenting with lower gastrointestinal symptoms; a retrospective primary care study in the United Kingdom

Abstract

Abstract Background Faecal calprotectin (FC) is of value in differentiating Inflammatory Bowel Disease (IBD) from other causes of lower gastrointestinal (GI) symptoms and is recommended in national guidance. This study aims to examine the role of and factors associated with faecal calprotectin requesting in primary care. Methods Retrospective open cohort study using Clinical Practice Research Datalink (CPRD Aurum) of adults aged 18 years and above with lower GI symptoms between 2015 and 2019. FC requested 30 days before to 3 months after a lower GI symptom record in primary care were included. Logistic regression model was used to explore patient level factors associated with FC testing. Referral pathways and outcomes in terms of IBD diagnoses of patients with and without FC testing were also examined. Results Of 741,190 symptomatic patients, only 18,320 (2.5%) patients had a FC requested in primary care: median age 38.3 (IQR 28.9-50.7); 51.4% females. The percentage of FC requests in symptomatic patients increased from 0.02% in 2010 to 4.4% in 2019 (p=0.001). FC value of <50 ug/g and 50-200 ug/g were predominantly seen in patients with abdominal pain (42.1% and 37.9% respectively) while FC > 200 ug/g was predominantly seen in patients with diarrhoea (45.3%). The only patients with a significant risk of IBD with a FC 50-200ug/g were patients with rectal bleeding (8%). Factors associated with less FC requesting included: increasing age (>70 years aOR 0.16 ( 95% CI 0.15-0.18); female (0.89,0.86-0.92); Black (0.61, 0.56-0.66) or Asian (0.75, 0.70-0.80) ethnicity; obesity (0.89,0.85-0.93); lower socioeconomic status (0.91,0.86-0.98); comorbidity score >2 (0.73,0.68-0.79); and current smoking (0.89,0.85-0.92). Patients with change in bowel habit (7.31,6.90-7.75); rectal bleeding (2.04,1.95-2.13); diarrhoea (2.88,2.78-2.99) as a presenting symptom compared to abdominal pain and ex-smokers (1.06,1.03-1.11) had more FC requests. Of patients referred with a FC >200 ug/g, 21.5% were diagnosed with IBD but only 2.9% of patients with a FC 50-200ug/g. 27.8% patients with a normal FC test result were still referred to secondary care, of which only 0.4% had IBD. Conclusion Despite an increase in FC requests in recent years, only 4.4% of patients with relevant lower GI symptoms had an FC requested in primary care as recommended. Despite a negative FC test, 27.8% of patients were still referred to secondary care with very few patients diagnosed with IBD (0.4%).