PROGNOSTIC VALUE OF ULTRASOUND ACTIVITY AND PARIETAL HEALING IN PATIENTS WITH CROHN'S DISEASE.

INTRODUCTION The "treat to target" strategy for the management of patients with Crohn's disease (CD) requires simple, reliable and non-invasive tools for continuous monitoring of the disease. Intestinal ultrasound is postulated as an emerging technique that could be very useful in this field. MATERIAL AND METHODS Patients who had undergone an intestinal ultrasound by clinical practice between February 2013 and October 2018 at our hospital were retrospectively included. The evolution of the patients during follow-up was assessed, based on the presence of ultrasound activity and the therapeutic changes based on the results. RESULTS 277 CD patients were included, the median follow-up time was 24 months (range 5-73 months). Among the patients included, signs of ultrasound inflammatory activity were identified in 166 patients (60%), of which treatment was escalated in 116 patients (70%) based on the results of the ultrasound. Among patients in whom ultrasound activity was identified, in 166 patients (60%), the evolution was less favourable than in those without activity, with a lower time until the next outbreak. Thus, the median disease-free survival (without outbreaks) after performing the ultrasound was 18 months when ultrasound activity was identified (although in most of the patients (70%) the treatment had been escalated) versus 47 months in patients without ultrasound activity, these differences being statistically significant (p <0.0001). Among the 111 patients without ultrasound activity, it was noted that those who achieved "parietal healing" (74 patients) had better evolution with a 12% subsequent outbreak vs 27% during follow-up (p = 0.05). Thus, at 3 years' follow-up, 15% of patients with parietal healing had an outbreak vs. 34% of those who had not normalized the ultrasound findings. CONCLUSION Intestinal ultrasound is a technique capable of detecting inflammatory activity in patients with Crohn's disease and the presence of ultrasound activity is a risk factor for a new outbreak of activity and / or clinical relapse. Likewise, the presence of PH provides a better evolution for patients during follow-up, so it could be a more precise objective to consider deep remission in CD, with intestinal ultrasound being a useful technique for this purpose.