Clinical characteristics of patients with pneumatosis intestinalis.

Background Several theories explaining the development of pneumatosis intestinalis (PI) have been reported, but a substantial portion of cases have been idiopathic. Additionally, predictors of bowel ischaemia in PI have not been fully investigated, while PI with bowel ischaemia has deteriorated overall outcomes of PI. Methods Sixty-four patients diagnosed with PI (2009-2019) were allocated to two groups: with (group 1; n = 15 (23%)) and without (group 2; n = 49 (77%)) bowel ischaemia. Fourteen patients underwent emergency surgery, and bowel ischaemia was identified in nine (64%). Six patients in group 1 were diagnosed with bowel ischaemia, and were treated palliatively. On medical charts, we determined underlying conditions of PI, compared the characteristics and outcomes between the groups, and identified the predictors of bowel ischaemia. Results Group 1 patients more commonly showed abdominal pain, lower base excess, higher C-reactive protein concentrations, higher white blood cell counts and higher neutrophil-to-lymphocyte ratios, and more frequent comorbid ascites, free air and hepatic portal vein gas. Of nine bowel ischaemia surgery patients, three (33%) died; all because of anastomotic leak. All except three patients in group 2, who presented with aspiration pneumonia, responded to treatment. Only one patient had an unknown cause (1/64, 1.6%), and various underlying conditions in secondary PI were confirmed. Conclusion Idiopathic PI may be identified rarely using current imaging and knowledge, but outcomes in PI patients with bowel ischaemia remain unsatisfactory. Earlier identification of bowel ischaemia by various specialists in accordance with predictors of bowel ischaemia could improve overall outcomes in PI patients.