Pneumatosis intestinalis (PI) is a striking radiological diagnosis. Formerly a rare diagnostic finding, it is becoming more frequently diagnosed due to the wider availability and improvement of computed tomography scan imaging. Once associated only with poor outcome, its clinical and prognostic significance nowadays has to be cross-referenced to the nature of the underlying condition. Multiple mechanisms of pathogenesis have been debated and multiple causes have been detected during the years. All this contributes to creating a broad range of clinical and radiological presentations. The management of patients presenting PI is related to the determining cause if it is identified. Otherwise, in particular if an association with portal venous gas and/or pneumoperitoneum is present, the eventual decision between surgery and non-operative management is challenging, even for stable patients, since this clinical condition is traditionally associated to intestinal ischemia and consequently to pending clinical collapse if not treated. Considering the wide variety of origin and outcomes, PI still remains for surgeons a demanding clinical entity. The manuscript is an updated narrative review and gives some suggestions that may help make the decisional process easier, identifying patients who can benefit from surgical intervention and those who can benefit from non-operative management avoiding unnecessary procedures.

While pneumatosis intestinalis (PI) is a rare condition associated with a wide variety of underlying diseases, PI with intraperitoneal free air and ascites is extremely uncommon and is difficult to distinguish from diffuse peritonitis. We herein describe the case of an 87-year-old male who was admitted to our hospital with abdominal pain, distension and nausea. Abdominal plain radiography and computed tomography revealed intramural air collection in the entire intestine, intraperitoneal free air and ascites. Although we first suspected bowel necrosis and perforation, his physical findings and the properties of the diagnostic abdominal paracentesis did not support this diagnosis. Therefore, we selected conservative management, and the intramural air, intraperitoneal free air and ascites disappeared 1 week later. Recognition of the possible presence of non-surgical PI and intraperitoneal free air, although it is extremely rare, is important to avoid a misdiagnosis and the associated unnecessary surgical intervention.

We present the case of an elderly woman who developed a bowel perforation related to pneumatosis intestinalis, 33 years after a jejuno-ileal bypass for severe obesity. Final histological examination revealed the presence of dysplasia in the resected specimen. On the basis of our case and a review of the literature, we discuss the etiopathogenesis, the clinical aspects and the treatment of this rare condition.