Lactulose-induced pneumatosis intestinalis following colonoscopy: a case report.

Pneumatosis intestinalis (PI) occurs when gas is discovered in the intestinal wall and is categorized into two types: primary PI which is idiopathic and mainly occurs in the colon, and secondary PI which occurs more often in the small bowel but has variable presentation and etiology. We report a case of a patient status post-orthotopic deceased liver transplantation complicated by a portal vein thrombus on chronic lactulose for portosystemic encephalopathy who presented due to pyelonephritis and persistent diarrhea. The patient underwent colonoscopy with random biopsies and subsequently developed acute sepsis with Escherichia coli bacteremia. The findings of PI were noted on computed tomography imaging obtained 5 days post-colonoscopy, due to persistent post-procedure abdominal pain. The patient was treated with discontinuation of lactulose, supportive care, and antibiotics for her bacteremia with resolution of her PI 3 days later. This suggests that a combination of factors may lead to the development of PI, and while some cases require emergent intervention including surgery, others may be treated conservatively. Awareness of risk factors that may precipitate PI and specific clinical predictors may help to both mitigate and manage PI appropriately.