Hyperbaric Oxygen Enabled a Transition to Oral Steroids in an Acute Severe Ulcerative Colitis Flare.

Background: Ulcerative colitis (UC) is characterized in part by a dysregulated response to tissue hypoxia. While intravenous (IV) steroids are the mainstay of treatment for acute severe UC (ASUC), up to one-third of patients are refractory to steroids alone and require rescue therapy. Case Description: A 71-year-old female with extensive UC on infliximab presented with abdominal pain and more than 10 bloody bowel movements per day. Her infliximab concentration was undetectable with a positive antibody level. Flexible sigmoidoscopy on hospital day (HD)1 showed Mayo 3 colitis; biopsies for CMV were negative. She was started on hydrocortisone IV with improvement in her CRP from 56 to 40 mg/L. She also received 1 dose of vedolizumab. Hyperbaric treatments were offered but declined. By HD5, she was clinically improved, with a CRP of 9 mg/L. She was transitioned from IV to oral steroids. After starting oral steroids her symptoms relapsed, her CRP increased from 9 to 48 mg/L, and IV steroids were reinitiated on HD6. Hyperbaric medicine was reconsulted and she completed 5 hyperbaric oxygen (HBO2) treatments (HD 7-11) with prompt reduction in CRP, stool frequency, and bleeding. After 3 HBO2 treatments, she transitioned successfully from IV to oral steroids on HD9. Conclusions: This case demonstrates the potential of HBO2 therapy to help UC patients transition successfully from IV to oral steroids who were previously refractory to de-escalation. HBO2 therapy may be considered as an adjunctive treatment for patients with ASUC to potentiate the effects of standard therapies and avoid progression to colectomy.