Background/Purpose: It is estimated that between 5 and 10% of patients with spondyloarthritis (SpA) are associated with inflammatory bowel disease (IBD).
The purpose of our study was to assess the usefulness of the determination of FC for the diagnosis of IBD in patients diagnosed with SpA without suggestive manifestations or previous diagnosis of IBD.

Methods: Unicentric, observational cross-sectional study with prospective clinical data collection. We included patients consecutively selected in a Rheumatology Clinic diagnosed of SpA who fulfilled ASAS criteria and who did not present digestive symptoms suggestive of IBD (chronic diarrhea, rectal bleeding, perianal disease, chronic abdominal pain -persistent or recurrent-). Demographic, clinical and analytical data of SpA (uveitis, HLAB27, acute phase reactants), treatments and FC were collected, establishing as a pathological FC cut-off point >50 mg/Kg. For patients on NSAIDs, suspension was recommended two weeks prior to collection of stool samples. Patients with a positive FC test underwent ileocolonoscopy. Biopsies (between 4 and 12) of colon and terminal ileum were taken for pathological study.
A descriptive analysis of the collected variables and a comparative analysis of the baseline characteristics for the groups (CF>50mg/Kg and <50mg/KG) were carried out. Qualitative data were compared using the chi-square test and Fisher’s exact test, for quantitative data between two groups, a t’Student test was used for independent data as a parametric test and the Mann -Whitney U test as a non-parametric test. The statistical significance considered was p<0.05.

Results: Ninety nine patients were included. 50% men, average age 46+11 years. BASDAI of 3.7+2.5. 79% were HLAB27 positive, 31% had high ESR levels (>20mm/h) and 9% had elevated CRP (>10mg/L). 49 patients (49.5%) had high FC levels, with mean levels of 276mg/kg (range 52-3,038). Ileocolonoscopy was performed in 47 of these patients, with alterations in 12 (25.5%), of which 4 (8.5%) were classified histologically as IBD type Crohn’s disease. Among patients with FC >50 mg/kg, a greater number of cases of IBD were identified (28.6%) in the subgroup of patients with high CRP, as compared with patients with normal CRP (5.9%) (p=0.045). The subgroup of patients with high ESR also presented a prevalence higher (14.3%) than patients with normal ESR (6.9%) (p=0.393). Patients with a history of uveitis also had a higher prevalence of IBD (25% vs 5.7%; p=0.090). There were no significant differences in relation to HLAB27 nor in relation to the history of psoriasis. No statistically significant differences were found in the mean FC levels between patients with high FC who were diagnosed with IBD and those who did not (328mg/kg vs 296mg/kg).

Conclusion: In our study, the group of patients with FC>50 mg/Kg presented an IBD prevalence of 8,5%, suggesting the usefulness of this biomarker in the screening of IBD among patients with SpA. The diagnosis of IBD was found to be associated with high FC levels, CRP>10 mg/L, high ESR or a history of uveitis.

« Back to 2018 ACR/ARHP Annual Meeting

ACR Meeting Abstracts - https://acrabstracts.org/abstract/utility-of-fecal-calprotectin-levels-for-the-diagnosis-of-inflammatory-bowel-disease-in-patients-with-spondylorarthritis/