LAUSR

Background Intestinal inflammation is seen in half of patients with spondyloarthropathy (SpA), and can be detected by faecal calprotectin(Fcal)1. Small bowel inflammation is detected by MR Enterography (MRE), accurately2. Objectives Definition of MRE changes in SpA patients with high Fcal levels. Methods A total of 231 SpA patients, 50 healthy subjects and 50 inflammatory bowel disease (IBD) patients were included. Stool specimens were obtained and data on BASDAI scores, abdominal pain, diarrhoea, NSAID and TNF inhibitor usage were noted. Fcal was measured by IDK ELISA 2 weeks after the cessation of NSAID. MREs were obtained in Fcal >50 µg/g SpA patients. Contrast enhanced MRE was performed using 3 Tesla MRI device after 6 hours of fasting. Results Demographic and clinical characteristics are summarised in table 1 and flow diagram (figure 1). Median Fcal of SpA patients was higher than healthy controls and lower than IBD patients. Fcal levels were high in 15 (33.3%) of 45 healthy cases and all but two of them were NSAID users. The Fcal test was high in 45.9% (n=106) of SpA patients. There was no correlation between BASDAI index and Fcal results (r=0,08 p=0,42). Mean Fcal levels of active and in remission patients were 78.2±20 and 77.8±7.02 µg/g respectively (p=0.97). Fifty-two of the Fcal-high SpA patients were retested after cessation of NSAIDs for 14 days. In 15 patients Fcal levels remained elevated. MRE was performed 33 SpA patients with high Fcal levels. MRE findings were observed in 29 of 33 (87%) patients. Four out of 33 (%12,1) MRE imaging was totally normal. Patients with MRE findings had higher median Fcal levels than those with normal MRE imaging (98 vs. 52 µg/g p=0.002). All patients had increased mesenteric fat density and presence of mesenteric lymph nodes. Increased mesenteric vascularity (28/29), increased bowel wall enhancement (23/29) and thickness (18/29) were frequently detected. Approximately one-third of the patients had a luminal stricture (13/29) and loss of haustration (12/13).Abstract FRI0568 – Table 1 Demographic and clinical characteristics SpA (n=231) Healthy Controls (n=45) IBD (n=50) P Value (SpA vs Healthy Cotrols) Age (Mean±SD) 45.2±9.8 43.4±14.9 39.9±13.1 p=0.33 Gender (Female/Male) 117/114 27/18 18/32 p=0.25 NSAID Users (%) %54.8 %53.3 %0 p=0.85 NSAID dose/2 wks 8.8±8.3 10,6±8.3 0 p=0.37 Anti-TNF users (%) %53.0 %0 %36.0 BASDAI (Mean±SD) 2,58±2,16 BASDAI≥4 (n/%) 60/194 (%26) Fcal (Median, Min-Max) 45.4 (0–830) 34.7 (2–324) 69.5 (0–840) p=0.004 Fcal high (>50 µg/g) (%) %45.9 (n=106) %33.3 (n=15) %58.0 (n=29) p=0.12 Fcal of NSAID Users (Median, Min-Max) 63 (0–830) 54 (2–324) p=0.30 Fcal of non-NSAID Users (Median, Min-Max) 27 (0–507) 16 (2–72) p=0.06 Conclusions In SpA patients with high Fcal levels MRE detected inflammation of mucosal as well as serosal surfaces, as in early CD. References [1] Cypers H. Elevated Calprotectin Levels Reveal Bowel Inflammation in Spondyloarthritis. ARD75:1357–62. [2] Toshimitsu Fujii. Current Progress of Endoscopy in Inflammatory Bowel Disease: Mr Enterography, Springer2018:57–70. Disclosure of Interest None declared