Autoimmune enteropathy and primary biliary cholangitis after proctocolectomy for ulcerative colitis: A case report and review of the literature.

Background: Autoimmune enteropathy (AIE) and primary biliary cholangitis (PBC) are both immune-mediated diseases. AIE or PBC complicated with ulcerative colitis (UC) are rare. There are no cases of AIE and PBC diagnosed after proctocolectomy for UC reported before, and the pathogenesis of these comorbidities has not been revealed.

Case Summary: A middle-aged woman diagnosed with UC underwent subtotal colectomy and ileostomy due to the steroid-resistant refractory disease, and a restorative proctectomy with ileal pouch-anal anastomosis and proximal neoileostomy was postponed due to active residual rectal inflammation in January 2016. A few months after the neoileostomy, she began to suffer from recurrent episodes of watery diarrhea. She was diagnosed with postcolectomy enteritis and stoma closure acquired a good therapeutic effect. However, her symptoms of diarrhea relapsed in 2019, with different histological features of endoscopic biopsies compared with 2016, which showed apoptotic bodies, a lack of goblet and Paneth cells, and villous blunting. A diagnosis of AIE was established, and the patient's stool volume decreased dramatically with the treatment of methylprednisolone 60 mg/d for 1 wk and tacrolimus 3 mg/d for 4 d. Meanwhile, her constantly evaluated cholestatic enzymes and high titers of antimitochondrial antibodies indicated the diagnosis of PBC, and treatment with ursodeoxycholic acid (16 mg/kg per day) achieved satisfactory results.

Conclusion: Some immune-mediated diseases may be promoted by operation due to microbial alterations in UC patients. Continuous follow-up is essential for UC patients with postoperative complications.