P401 Confocal laser endomicroscopy predicts response in patients with acute inflammatory bowel disease undergoing anti-integrin therapy with vedolizumab
M. Ellrichmann*1, J. Bethge1, G. Aust1, A. Arlt1, B. Brandt1, S. Zeissig1, 2, S. Nikolaus1, K. Aden1, S. Schreiber1
1University Hospital Schleswig-Holstein, Campus Kiel, Medical Department I, Kiel, Germany, 2University Hospital Dresden, Department of Gastroenterology, Dresden, Germany
Endoscopic assessment of inflammation in Inflammatory bowel disease (IBD) is limited to superficial criteria, exhibit a significant interobserver variability and is not applicable for the evaluation of early therapy response in patients undergoing anti-integrin therapies (Vedolizumab, VDO). Confocal laserendomicroscopy (CLE) allows real-time visualisation of vascular patterns, blood flow and potential crypt deformation and might therefore be a suitable method for an exact quantification of inflammation in IBD.
Aim: To evaluate CLE for quantification of the level of inflammation in IBD patients undergoing VDO therapy as a marker for early therapy response.
In total, 20 patients (10 m) with active IBD and involvement of the distal colon were recruited (11aUC; 9aCD) for probe based CLE (Cellvizio) in the sigmoid colon before and 2/6/14 wk after initiation of therapy with VDO. After injection of 2.5 ml fluorescein the following CLE criteria were quantified: Time to mucosal accumulation of fluorescein, capillary diameter, crypt diameter. Data were correlated to endoscopic Mayo scores. Data are presented as mean ± SD.
Response to therapy (defined as clinical remission at wk 14) was achieved in 60% of patients (12/20) after 14 wk of therapy. Time to mucosal accumulation of fluorescein was similar in all patients before therapy (8.8 ± 4.5 sec). In patients with later response time to accumulation significantly decelerated within 2 wk (14.6 ± 4.9 sec) compared with patients without response (9.8 ± 4.5 sec.; p = 0.03). Patients with clinical response showed significantly dilated capillaries (17.5 ± 2.4 µm) before therapy compared with non-responders (13.1 ± 0.9 µm; p = 0.001). In case of therapy response a significant reduction of capillary diameters was observed (p = 0.001), whereas in patients without response the capillary diameter remained unchanged (p > 0.05).
In responders crypts were significantly dilated before therapy with an outer diameter of 117.1 ± 18.4 µm in comparison with treatment failures (95.3 ± 14.8 µm; p = 0.01). VDO therapy induced a significant reduction of crypt diameter in responders (p = 0.001), no changes were observed with non-response (p = 0.3). The mean Mayo score showed no significant difference at wk 2 between responders and non-responders.
Endomicroscopic real-time visualisation of blood flow, vascular pattern and mucosal changes allows an exact quantification of the level of inflammation in IBD. The assessed criteria proved to be reliable to predict therapy response in patients undergoing VDO therapy. Mucosal healing seems to be a late marker to evaluate response to VDO therapy and is preceded by dynamic changes evaluated by CLE. (Support by BMBF emed)