title: Pneumatosis cystoides intestinalis presenting as pneumoperitoneum in a patient with chronic obstructive pulmonary disease: a case report.
abstract: BACKGROUND
  Pneumatosis cystoides intestinalis, marked by numerous gas-filled cysts in the intestinal wall and submucosa or intestinal submucosa, is a very uncommon condition.
  
  
  METHODS
  A 79-year-old Asian man presented to our emergency department after 2 days of lower abdominal pain with nausea and constipation. His past medical history included chronic obstructive pulmonary disease and he had been treated with home oxygen therapy. The patient was hemodynamically stable and had mild generalized abdominal pain and a soft, distended abdomen without signs of peritonism. A computed tomography scan showed diffuse intraluminal gas and intraperitoneal free gas. Based on the images, a clinical diagnosis of pneumatosis cystoides intestinalis with pneumoperitoneum was made. Considering the patient's physical examination, the peritoneal free air was drained by aspiration and he was observed for 12 h, but remained well. Abdominal symptoms and pneumoperitineum resolved after drainage of the peritoneal air by aspiration. The suspected etiopathogenic mechanism of pneumatosis cystoides intestinalis in the presented patient may have been alveolar air leakage secondary to high airway pressure due to chronic obstructive pulmonary disease; air leakage from an alveolar rupture may have traveled to the retroperitoneum through the mediastinal vessels and entered the mesentery of the bowel.
  
  
  CONCLUSIONS
  Emergency physicians should be aware of the potential development of pneumatosis cystoides intestinalis in chronic obstructive pulmonary disease patients.
authors.affiliation: Department of Emergency and Critical Care Medicine, Okayama University Graduate School of, Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama-shi, Okayama, 700-8558, Japan.
authors.forename: Atsuyoshi
authors.initials: A
authors.lastname: Iida
authors.affiliation: Department of Emergency and Critical Care Medicine, Okayama University Graduate School of, Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama-shi, Okayama, 700-8558, Japan.
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Naito
authors.affiliation: Department of Emergency and Critical Care Medicine, Okayama University Graduate School of, Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama-shi, Okayama, 700-8558, Japan.
authors.forename: Kohei
authors.initials: K
authors.lastname: Tsukahara
authors.affiliation: Department of Emergency and Critical Care Medicine, Okayama University Graduate School of, Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama-shi, Okayama, 700-8558, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Yumoto
authors.affiliation: Department of Emergency and Critical Care Medicine, Okayama University Graduate School of, Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama-shi, Okayama, 700-8558, Japan.
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Nosaka
authors.affiliation: Department of Emergency and Critical Care Medicine, Okayama University Graduate School of, Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama-shi, Okayama, 700-8558, Japan.
authors.forename: Shinnichi
authors.initials: S
authors.lastname: Kawana
authors.affiliation: Department of Emergency and Critical Care Medicine, Okayama University Graduate School of, Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama-shi, Okayama, 700-8558, Japan.
authors.forename: Keiji
authors.initials: K
authors.lastname: Sato
authors.affiliation: Department of Emergency Medicine, Kobe Tokusyukai Hospital, Kobe, Japan.
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Takeuchi
authors.affiliation: Department of Emergency Medicine, Kobe Tokusyukai Hospital, Kobe, Japan.
authors.forename: Jyunichi
authors.initials: J
authors.lastname: Soneda
authors.affiliation: Department of Emergency and Critical Care Medicine, Okayama University Graduate School of, Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama-shi, Okayama, 700-8558, Japan. qq-nakao@okayama-u.ac.jp.|Department of Emergency Medicine, Kobe Tokusyukai Hospital, Kobe, Japan. qq-nakao@okayama-u.ac.jp.
authors.forename: Atsunori
authors.initials: A
authors.lastname: Nakao
mesh_terms: D000368:Aged; D044682:Colon, Ascending / Q000000981:diagnostic imaging; D044684:Colon, Transverse / Q000000981:diagnostic imaging; D000072700:Conservative Treatment; D003937:Diagnosis, Differential; D006801:Humans; D007082:Ileum / Q000000981:diagnostic imaging; D008297:Male; D011006:Pneumatosis Cystoides Intestinalis / Q000150:complications* / Q000000981:diagnostic imaging; D011027:Pneumoperitoneum / Q000209:etiology*; D029424:Pulmonary Disease, Chronic Obstructive / Q000150:complications* / Q000000981:diagnostic imaging; D011859:Radiography; D014057:Tomography, X-Ray Computed
keywords: Benign disease; Computed tomography; Intramural gas; Intraperitoneal free air