Submit Manuscript | http://medcraveonline.com Introduction Pneumatosis intestinalis (PI) is a pathological condition defned as collection of gas within the intestinal wall, typically diagnosed in CT scans. Usually the gas is located to the colon (46 %), the small bowel (27 %), the stomach (5 %) or in combined patterns (22 %). 1 In the most severe cases PI is caused by potentially life-threatening intestinal ischemia, which indicates the need for immediate surgical treatment. But in fact there is a broad variety of benign to severe causes for PI ranging from obstruction, cancer, volvulus, ulcer, hernia, trauma to infammatory bowel diseases, diverticulitis, iatrogenic causes and viral infection. 2,3 We present herein the case of a 19 year- old male patient, who developed PI following hematopoietic stem cell transplantation (HSCT) after acute myeloic leukemia (AML) with concomitant norovirus infection. Case report The 19 year-old male patient entered the hospital through the emergency department with a cough, fever of 38.9°C and diarrhea of 3-4 times per day. He suffered from AML type FAB M6 which had frst been diagnosed 9 months before. Following diagnosis the AML has been treated by induction chemotherapy (cytarabine and daunorubicin, 7+3 regimen) and 2 cycles of consolidation chemotherapy with cytarabine followed by haploidentical stem cell transplantation donated by his mother 4 months ago. The respiratory symptoms caused by an acute graft-versus-host disease (GvHD) of the lung improved rapidly under intensifed immunosuppressive therapy with prednisolone and mycophenolic acid. However, during the further course he developed diarrhea, which got worse with defecations up to 20 times per day and the need for intravenous potassium substitution. The virological testing of the stools revealed norovirus infection, while the tests for adeno- and rotavirus and bacterial infections were negative. A GvHD of the colon was excluded by colonoscopy, as a biopsy of the mucosa revealed signs of acute infection without clear stigmata of GvHD. Under reduction of the immunosuppressive medication the stool frequency decreased to 4 times per day and the patient could fnally be dismissed from the hospital. To this time, no specifc therapy deemed necessary. A few days later he was readmitted to the hospital for fever of 38.6°C and a cough. A CT scan of the chest showed symmetrical infammatory infltrates of the lungs. Additionally a massive PI and pneumoperitoneum was detected in the lower sections. The subsequent CT scan of the abdomen revealed pneumatosis mainly localized to the colon and also free abdominal air, while portal venous gas (PVG) could be excluded (Figure 1). Under immunosuppression the leucocyte count was 1.4 G/l and thus not usable for detection of infammation or infection. The CRP (2.0 mg/dl) and lactate levels (2.2 mmol/l) were only slightly elevated. Clinically, the patient had an almost asymptomatic abdomen with only a slight tenderness but no abdominal guarding and lively bowel sounds. At frst an interdisciplinary decision to perform a conservative treatment approach was made by the surgical and gastroenterological consultant, due to the benign symptomatology and the abdominal conditions. Antibiotic (meropenem and metronidazole), antiviral (ganciclovir) and supportive therapy (high-calorie diet) was conducted. Although infection signs continuously decreased under this treatment and the patient remained stable, further discussions ended up with indication for exploratory laparoscopy, as due to the immunosuppression of the patient, clinical signs could be misleading. After informed consent and preoperative preparation, the patient was brought to the operating room and diagnostic laparoscopy was performed (Figure 2). During laparoscopy extensive pneumatosis of the complete colon with focus to the transverse colon became apparent. The small intestine was not affected by pneumatosis. Particular attention was spent to the appendix, which was also without pathological fndings. The liver and the gallbladder were unremarkable. Fortunately, there were no signs of perforation, ischemia or infammation, so no further intervention had to be performed. After taking a smear of the serous ascites a drainage tube was inserted and the operation fnished. The patient Gastroenterol Hepatol Open Access. 2018;9(2):92‒95 92 © 2018 Reischl et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and build upon your work non-commercially. Massive pneumatosis intestinalis and free abdominal air: Is surgery always necessary? Volume 9 Issue 2 - 2018 Stefan Reischl, Ihsan Ekin Demir, Philipp- Alexander Neumann, Helmut Friess, Dirk Wilhelm Department of Surgery, Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Germany Correspondence: Stefan Reischl, Department of Surgery, Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Munich, Germany, Email stefan.reischl@tum.de Received: February 12, 2018 | Published: April 16, 2018 Abstract Pneumatosis intestinalis can have various causes, ranging from benign to life-threatening. In some cases diagnosis is followed by immediate surgery to rule out mesenteric ischemia. Here we report the case of a 19 year-old patient who was incidentally diagnosed with massive pneumatosis intestinalis and free abdominal air following norovirus infection after hematopoietic stem cell transplantation for acute myeloic leukemia. Although the patient was almost completely asymptomatic, diagnostic laparoscopy was performed to rule out perforation or ischemia. Intraoperatively, massive pneumatosis of the colon without any other pathological fndings was visible, so no further intervention was necessary and the patient could be discharged from hospital 5 days later. In this report we describe the case in detail and discuss upon the fact, whether diagnostic laparoscopy is mandatory in such cases. Keywords: Pneumatosis intestinalis, free abdominal air, norovirus, stem cell transplantation, acute myeloic leukemia, portal venous gas Gastroenterology & Hepatology: Open Access Case Report Open Access