Case Report: Successful anti-TNF antibody therapy in steroid-dependent segmental colitis associated with diverticulosis and concomitant ulcerative colitis.

Segmental colitis associated with diverticulosis (SCAD) is a rare inflammatory condition limited to colonic segments affected by diverticulosis. Its coexistence with ulcerative colitis (UC) is extremely rare and poses a diagnostic and therapeutic challenge. We report the case of a 56-year-old woman with a history of sigmoidectomy for recurrent sigmoid diverticulitis, who subsequently developed SCAD in the residual diverticula adjacent to the anastomosis, along with concomitant left-sided UC. Despite treatment with mesalazine and vedolizumab and rectal healing of UC, SCAD was therapy-refractory. The use of the anti-TNF antibody adalimumab, intensified to 40 mg weekly, resulted in complete clinical, endoscopic, and histologic remission of both SCAD and UC. At five years of follow-up to date, the patient remains in sustained, steroid-free remission without adverse events. This case highlights the possible coexistence of SCAD and UC and suggests adalimumab as a promising and sustained treatment option in refractory SCAD, even in the setting of coexisting UC.