We report a 21-year-old man who experienced symptoms of colitis following autologous TBI-conditioned PBSC transplantation, which persisted despite conventional treatment. Abdominal echography showed a thickened, stratified wall of the cecum, of the right colon and of part of the transverse colon. Hyperbaric oxygen therapy (20 sessions of 100% oxygen inhalation at 2.5 bar for 120 min in a hyperbaric chamber) achieved a prompt clinical recovery as well as complete disappearance of the ultrasound abnormalities.

Favre, Ventura, Nardi, Massimetti, Papineschi, Macchia, , , (1998). Hyperbaric oxygen therapy in a case of post-total body irradiation colitis. Bone marrow transplantation, 1998 Mar;21(5):519-20. https://www.ncbi.nlm.nih.gov/pubmed/9535045