Clinical characteristics and prediction of the asymptomatic phenotype of pneumatosis intestinalis in critically ill patients: a retrospective observational study

Aim: The differences in clinical characteristics between benign asymptomatic and symptomatic pneumatosis intestinalis (PI) remain unknown. This study aimed to reveal the clinical characteristics of PI in critically ill patients.

Methods: This was a retrospective observational study undertaken between 2013 and 2017 in a single facility. Patients with PI were enrolled. Pneumatosis intestinalis was diagnosed using computed tomography, and clinical data were collected. Pathologic PI refers to PI with bowel ischemia. Asymptomatic PI refers to PI with a benign etiology.

Results: There were 17 patients with pathologic PI and 31 with asymptomatic PI. Pathologic PI was detected at day 4 of hospital stay, and asymptomatic PI was detected at day 30 of hospital stay (P < 0.01). The symptoms that were different between pathologic and asymptomatic PI were acute diarrhea (18% and 65%, P = 0.01), C-reactive protein level elevation (9.9 and 2.1 mg/dL, P = 0.01), and systemic inflammatory reaction syndrome (100% and 13%, P < 0.01). Computed tomography findings showed a difference in the occurrence of ascites collection (94% versus 23%, P < 0.01) and PI of the ascending colon (47% versus 80%, P = 0.02). Hospital mortality of pathologic PI was 88%, whereas all patients with benign PI survived. The positive likelihood ratio of acute diarrhea with PI of the ascending colon to diagnose benign PI was 7.33 (1.11-48.5).

Conclusions: Pneumatosis intestinalis of the ascending colon that occurs in the post-intensive care phase with a poor inflammatory reaction, acute diarrhea, and no ascites collection could be benign. In other cases, bowel ischemia should be promptly ruled out.