More air, air: a case of spontaneous pneumomediastinum associated with crohn's ileocolitis

SESSION TITLE: Disorders of the Mediastinum Case Report Posters 2 SESSION TYPE: Case Report Posters PRESENTED ON: 10/09/2023 02:10 pm - 02:55 pm INTRODUCTION: Extraintestinal manifestations of inflammatory bowel disease (IBD) are often linked to disease activity. Airway and pulmonary involvement are less common, however can include interstitial lung disease, pulmonary fibrosis, vasculitis, bronchitis, laryngotracheitis, and sarcoidosis. We present a rare case of spontaneous pneumomediastinum in the setting of active Crohn's ileocolitis. CASE PRESENTATION: An 18-year-old male with a history of ileocolonic Crohn's disease treated with weekly Humira, hereditary spherocytosis, and Gilbert syndrome presented to the hospital for evaluation of 3 days abdominal pain, nausea and nonbloody emesis. He denied any respiratory complaints, and was non-hypoxemic on room air. He had no recent illnesses, esophageal or colonic instrumentation, intubations, and no family history of pulmonary blebs or pneumothorax. He is a never-smoker and denies vaping or smoking marijuana. Labs were notable only for an elevated CRP of 301 mg/L. CT of the abdomen/pelvis showed enterocolitis, splenomegaly, and incidentally noted mediastinal air without pneumoperitoneum or perforated viscus. CT of the chest showed extensive pneumomediastinum extending from the superior to inferior mediastinum, as well as subcutaneous emphysema along the neck and right axilla (Figures 1 & 2). There was no evidence of pulmonary blebs, pneumothorax, or airway rupture/defects. There was initial concern for a possible esophageal rupture however no extraluminal leak was identified on a barium esophagram (Figure 3). The pneumomediastinum was ultimately attributed to increased intrathoracic pressure related to emesis in the setting of severe colitis due to inflammatory bowel disease. He was treated for inflammatory colitis. A repeat CT of the chest performed on an outpatient basis showed complete resolution of the pneumomediastinum after 8 weeks. DISCUSSION: Pneumomediastinum is a rare finding that can be seen in cases of airway trauma, upper respiratory tract infection by gas-forming organisms, or in cases of increased alveolar pressure. In IBD, pneumomediastinum is most frequently described as a complication of procedures involving GI tract instrumentation such as esophagogastroduodenoscopy or colonoscopy. Spontaneous pneumomediastinum associated with active IBD is a rare entity, with only nine reported cases in the absence of perforation or pneumoperitoneum. It is postulated to occur as a result of the severe colitis, most commonly ulcerative colitis, creating microscopic perforations which allow air to travel into the retroperitoneum, through the diaphragmatic hiatus and into the mediastinum. CONCLUSIONS: A diligent search for alternative causes of pneumomediastinum in patients with IBD, primarily perforation following GI tract instrumentation, is imperative. In the absence of a clear inciting etiology, management is nonoperative and entails treatment of the underlying IBD, as well as future reexamination for resolution. REFERENCE #1: Mihatov N, Fenves AZ. Pneumomediastinum in inflammatory bowel disease. Proc (Bayl Univ Med Cent). 2015 Jul;28(3):347-9. REFERENCE #2: Cohen ME, Kleinman MS. Pneumomediastinum during relapse of ulcerative colitis. Am J Gastroenterol 1997;92(12):2306–2307. REFERENCE #3: Annah.zi A, Poly.k I, Nagy F, Wittmann T, Moln.r T. "Ulcerative crepitus"—a case with subcutaneous emphysema and pneumomediastinum without colonic perforation or toxic megacolon in ulcerative colitis successfully treated conservatively. J Crohns Colitis 2012;6(6):717–719. DISCLOSURES: No relevant relationships by Peter Boshara No relevant relationships by Bhavinkumar Dalal