P651 Does ambient temperature alter faecal calprotectin levels?

S. Cauchi1, J. Schembri2, M. Muscat2, P. Ellul2

1Mater Dei Hospital- Malta, Department of Medicine, Kirkop, Malta, 2Mater Dei Hospital- Malta, Department of Gastroenterology, Msida, Malta

Background

Faecal Calprotectin (FCP) is a marker of intestinal inflammation and its measurement is useful in both the diagnosing and the evaluation of disease activity in patients with inflammatory bowel disease (IBD). Limited and conflicting evidence exists on the reliability of FCP as a stable marker at ambient temperature. While an adult publication suggested that FCP can be delivered to the laboratory at ambient temperature with reliable and consistent results, a recent publication in a paediatric cohort demonstrated that samples stored at 4 ˚C were more reliable than those kept at ambient temperature. The aim of the study was to evaluate if there is any variation in FCP levels depending on ambient temperature in patients in clinical remission.

Methods

Patients with IBD (Crohn`s disease {CD}; ulcerative colitis {UC}) who were in clinical, radiological and/or endoscopic remission in the previous 6 months were recruited. The FCP levels taken in between December 2018 and February 2019 (mean daytime temperature – 15.7ºC; range 4 – 19ºC) and those taken July–September 2019 (mean daytime temperature 29ºC; range 21–39ºC) were analysed. No patients had to have any change in IBD medications or any features of relapse during the study period. All recruited patients had to have two samples of FCP taken—one taken in winter and the other in summer.

Results

109 patients were recruited (males: 57 patients; 56% - CD). The mean patient age was 43.9 years (±3.313 SD; range 19–82 years). The mean FCP during the winter months was 135.6 mg/l (±20.9 SD) while that in summer was 121.9 mg/l (±24.1 SD). No statistically significant difference between the winter and summer months (p = 0.41). The mean winter FCP in CD was 122.2 mg/l (±27.5 SD) while that in UC was 147.0 mg/l (±31.4 SD) (p = 0.19). In the same patients, the mean summer FCP in CD was 128.3 mg/l (±31.8 SD) while in UC it was 114.95mg/l (±39.9 SD) (p = 0.73). While numerically, the levels of the FCP in UC were different, this was not statistically significant (p = 0.32). Further FCP analysis for the variables of age and gender did not reveal any significant differences.

Conclusion

These data demonstrate that FCP is a reliable marker of disease activity in routine clinical practice, when submitted to the laboratory at ambient temperatures. The ability of submitting the stool samples to the laboratory with only a few precautions, will undoubtedly ensure patient compliance in submitting stool samples. However further analysis in FCP variation in UC patients needs to be considered.