S111 Novel Use of a Biologic Agent for an Uncommon Complication of an Old Surgery: Successful Use of Ustekinumab for Kock Pouchitis

Background: Surgical colectomy has been documented in upwards of 10% of patients with ulcerative colitis (UC). Although proctocolectomy with ileal pouch anal anastomosis (IPAA) or end ileostomy are the most frequently offered operations for refractory uc, continent ileostomy (CI) with Kock pouch was offered to uc patients for decades prior to the adoption of IPAA. Although this procedure is now less common it is important for the inflammatory bowel disease (IBD) practitioner to be aware that patients with CI are subjected to similar complications as IPAA such as pouch inflammation related to pouchitis. We present a uc patient with subtotal colectomy and creation of a CI who developed severe and recurrent Kock pouch inflammation that was ultimately successfully treated with ustekinumab. Methods: A 64-year-old male with a medical history of uc with subtotal colectomy in 1970s with creation of a continent ileostomy 2007 presented due to severe and refractory diarrhea. The patient had a subtotal colectomy at the age of 16 followed by Kock pouch creation in his 30s that was complicated by valve failure, eventual valve removal and most recently had Barnett continent ileostomy placed in 2007. He had done well for many years without any uc therapy. However, in the fall of 2023 he developed severe diarrhea requiring hospitalization. Prior to our encounter patient had completed stool infectious work up which was negative along with trialing pancreatic enzyme supplementation, cholestyramine, and mesalamine without benefit. The patient was evaluated in our facility in January 2024 during which time a computed tomography enterography demonstrated pouch inflammation with a fecal calprotectin of 1628 mcg/g. Ileoscopy demonstrated erythema and ulcerations limited to the pouch with pathology demonstrating acute on chronic inflammation. Upper endoscopy also at that time was grossly normal although duodenal biopsies did demonstrate villous atrophy and in the setting of elevated trans tissue glutaminase there were concerns for celiac disease as the primary etiology of his diarrhea. At discharge he was advised on a gluten-free diet (GFD) and started budesonide for his observed pouch inflammation. One month later patient’s symptoms improved and subsequently was tapered off budesonide. However, 3 months after the initial encounter, patient reported recurrence of diarrhea despite adherence to a strict GFD. Due to the severe nature of his symptoms when tapering off steroids resulting in severe dehydration and pouch pathology demonstrating inflammation, there was concern for refractory pouchitis. The patient was subsequently started on ustekinumab based on insurance coverage. Results: Three months after initiation of ustekinumab, the patient reported complete resolution of symptoms. Conclusions: Discussion: although this surgical approach has become less common, it is important for IBD specialists to understand the potential complications that patients with CI may experience. Literature review has largely revealed documented biologic therapy for pouchitis in patients IPAA; however, there has been no documented use of ustekinumab as the biologic agent of choice or the use of biologic therapy in recurrent CI inflammation. Thus, this case represents a potential novel therapy for the use of ustekinumab in patients with Kock pouch inflammation.