Abstract
Background: Interleukin (IL)-23 exerts its effects by activating Th17 cells, resulting in high neutrophilic infiltration in the colonic mucosal epithelium. We have developed a scoring method for refining the Geboes score Grade 3 to identify active ulcerative colitis (UC) patients with high epithelial neutrophilic infiltration (Geboes Grade 3.2 or 3.3). Methods: Colonoscopy and histology findings were assessed using the Mayo endoscopic subscore (MES) and the Geboes score Grade 3. The percentage of crypts with neutrophilic infiltration, which was calculated as the number of crypts with neutrophilic infiltration/total crypts in a glass slide, was used to subclassify the Geboes score Grade 3 into Grades 3.0, 3.1, 3.2, and 3.3. Results: This scoring method was then applied to 30 enrolled patients (20 men; median age: 46 years), yielding the following distribution: Geboes Grade 3.0 in six (20%) patients, Grade 3.1 in seven (23%) patients, Grade 3.2 in sixteen (53%) patients, and Grade 3.3 in one (3%) patient. Of the 18 UC patients with MES 2, 5 (28%) were classified as Grade 3.1 and 12 (67%) were classified as Grade 3.2. One of the IL-23 antagonists, mirikizumab treatment, resulted in clinical and endoscopic improvements in 10 active UC patients who were classified as Geboes score ≥ 3.2. Conclusions: We developed a novel Geboes score Grade 3 scoring method and applied it to 30 patients; approximately 60% were classified as Grade 3.2 or higher. This method may help to identify UC patients who are likely to respond effectively to IL-23 antagonists.