Pneumatosis intestinalis, not always a surgical emergency

Transcription

1 Pneumatosis intestinalis, not always a surgical emergency Poster No.: C-2233 Congress: ECR 2012 Type: Educational Exhibit Authors: E. Vanhoutte, M. Lefere, R. Vanslembrouck, D. Bielen, G. De Hertogh, A. Wolthuis, D. Vanbeckevoort ; Leuven/BE, Louvain/ BE Keywords: Abdomen, Gastrointestinal tract, CT, Diagnostic procedure, Education, Ischaemia / Infarction, Chronic obstructive airways disease DOI: /ecr2012/C-2233 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 24

2 Learning objectives To illustrate the wide spectrum of diseases associated with pneumatosis intestinalis, ranging from benign to life-threatening. To highlight the additional signs which help in differentiating between benign and life-threatening pneumatosis intestinalis. To highlight that surgery is not mandatory in patients with pneumatosis intestinalis complicated with pneumoperitoneum. Page 2 of 24

3 Background Pneumatosis intestinalis (PI) is a sign that refers to the presence of intramural bowel gas in the submucosal or in the subserosal layers (Fig. 1 on page 6, Fig. 2 on page 6). 1 It is uncommon (0,03% ) and more seen in elderly. It is mostly present in the colon (also referred to as pneumatosis coli) and small bowel, rarely in the oesophagus and the stomach. PI can be primary (15%), but is usually secondary to underlying diseases (85%). Primary pneumatosis intestinalis, also known as pneumatosis cystoides intestinalis, is a benign idiopathic condition characterised by multiple thinwalled cysts in the submucosa or subserosa containing air. The secondary form is associated with more than 60 different diseases. The intramural gas presents more linear and streak-like rather than cystic. Secondary PI can be classified in benign and life-threatening PI, based on the course of the underlying disease. Causes are listed in Table 1 on page 7. Life-threatening PI is the well known alarming finding in acute diseases, for instant acute bowel ischemia, toxic megacolon and intestinal obstruction and implicates urgent surgery. Benign PI can be demonstrated in chronic diseases, e.g. lung fibrosis or Crohn's disease. Conservative treatment is often sufficient. In certain conditions PI is sometimes but not always an alarming finding (transplant patients, intestinal obstruction, infection). Page 3 of 24

4 Table 1: Spectrum of benign and life-threatening causes of pneumatosis intestinalis. Note that in transplanted patients or in patients with intestinal obstruction or infection, PI is not always a benign finding. References: - Leuven/BE The pathogenesis is not entirely known. Mechanical theory: dissection of gas into the bowel wall due to increased pressure in the lung via the mediastinum (eg. obstructive lung disease) or in the intestinal lumen (bowel obstruction). Bacterial theory: increased mucosal permeability causes gas-producing bacteriae to invade the intestinal wall. Mucosal injury can be caused by neutropenia, by leukemic or lymphatic infiltrates or by toxic effects of chemotherapeutic agents. The use of antibiotics and steroids may contribute to an altered enteric bacterial flora and overgrowth of fungi. Clinical presentation Primary PI and benign PI are overall asymptomatic. Nonspecific symptoms may be present, usually depending on the course of the underlying disease. Page 4 of 24

5 In life-threatening PI, peritoneal signs may be present in case of intestinal perforation. Therapy Traditionally the finding of PI was considered a surgical emergency, but currently several studies demonstrate that often surgery can be avoided. The radiological classification of PI in benign and life-threatening PI, in correlation with the clinical presentation and lab findings, can help to decide wether to operate or not. Page 5 of 24

6 Images for this section: Fig. 1: Histology of resected bowel wall showing pneumatosis intestinalis. Intramural gas is seen as air bubbles in the submucosa (orange arrows) or subserosa (red arrow). Page 6 of 24

7 Fig. 2: CT image of pneumatosis intestinalis (yellow arrow). Pneumoperitoneum is also present (red arrow). Page 7 of 24

8 Table 1: Spectrum of benign and life-threatening causes of pneumatosis intestinalis. Note that in transplanted patients or in patients with intestinal obstruction or infection, PI is not always a benign finding. Page 8 of 24

9 Imaging findings OR Procedure details Pneumatosis intestinalis (PI) can be seen on plain radiographic images, but CT-scan has a higher sensitivity in diagnosing PI and also provides information about the underlying disease (Fig. 3 on page 10, Fig. 4 on page 10 ). * Imaging findings in benign causes of PI: PI is not always an alarming sign (Table 1 on page 11) and it may sometimes contribute to extra useful information, eg.: 1 Pulmonary causes of PI are usually benign (Fig. 5 on page 12). PI in a patient with Crohn's disease is correlated with a higher severity of the )1 disease (Fig. 6 on page 13. * Imaging findings in life-threatening causes of PI: The presence of additional findings such as described below, increases the possibility of PI due to a life-threatening cause: Look for: bowel wall thickening, Fig. 7 on page 14 absent or intense mucosal enhancement, Fig. 8 on page 15 bowel dilatation, Fig. 9 on page 16 portal or portomesenteric venous gas, Fig. 10 on page 17 ascites, Fig. 11 on page 18 arterial or venous occlusion, Fig. 12 on page 19 free intraperitoneal air, Fig. 12 on page 19 BUT Pneumoperitoneum is not always an alarming sign (Fig. 13 on page 20). When free intraperitoneal air is the only additional sign in the presence of benign PI it can be treated conservatively, based on the hypothesis that free intraperitoneal air originates from ruptured serosal and subserosal cysts and no direct communication between the intestinal lumen and intraperitoneal space is present. Still, intestinal ischemia should always be excluded first. Page 9 of 24

10 Images for this section: Fig. 3: A 20 year-old patient with diarrhea after bone marrow transplantation. Plain radiograph shows pneumatosis intestinalis as linear air streaks in the wall of the ascending colon and transverse colon. Page 10 of 24

11 Fig. 4: A 20 year-old patient with diarrhea after bone marrow transplantation. Abdominal CT clearly demonstrates the pneumatosis intestinalis in the right hemi-colon. Stool culture identified Clostridium difficile infection. Antibiotics were started and the pneumatosis resolved - benign cause of PI. Page 11 of 24

12 Table 1: Spectrum of benign and life-threatening causes of pneumatosis intestinalis. Note that in transplanted patients or in patients with intestinal obstruction or infection, PI is not always a benign finding. Page 12 of 24

13 Fig. 5: PI as a solitary finding in a patient with lung disease is almost always benign. A 64-year-old male with mild epigastric pain and diarrhea after single lung transplant for idiopathic lung fibrosis (red arrow). Follow-up CT of the thorax showed pneumatosis intestinalis at the hepatic colic flexure (yellow arrow) - benign cause of PI. Page 13 of 24

14 Fig. 6: PI in a patient with Crohn's disease is correlated with a higher severity of the disease. CT shows ileitis of the preterminal ileum (blue arrow) with wall thickening and presence of pneumatosis intestinalis (yellow arrow) - benign cause of PI. Page 14 of 24

15 Fig. 7: Additional sign: bowel wall thickening. CT of a 69-year-old patient with portal vein thrombosis. Wall thickening (red arrow) of ileum and pneumatosis intestinalis (yellow arrow) of ascending colon is shown. Ascites (blue cross) is also visible. Signs all suggestive of severe intestinal ischemia - life-threatening cause of PI. Page 15 of 24

16 Fig. 8: Additional sign: absent mucosal enhacement. A 76-year-old man with transmural small bowel ischemia. Contrast-enhanced CT scan shows pneumatosis (yellow arrows) in mild dilated and fluid-filled small bowel loops and in the ascending colon. There is no wall enhancement (red arrows on the left) of these bowel loops, best seen in comparison to the normal wall enhancement of the descending colon (red arrow on the right). Pronounced mesenteric venous gas (blue arrows) is also present. The patient died shortly after - life-threatening cause of PI. Page 16 of 24

17 Fig. 9: Additional sign: bowel dilatation. Colonic obstruction due to a splenic flexure tumour (blue arrow). The caecum is dilated (red double arrow) and no enhancement of the paper-thin wall is seen with presence of intramural gas (yellow arrow): this is highly suggestive of ischemic complication due to manifest dilatation - life-threatening cause of PI. Page 17 of 24

18 Fig. 10: Additional sign: portal gas. A 89-year-old man with closed loop small bowel obstruction complicated with strangulation. Unenhanced CT scan shows gas in the portal vein mainstem (red arrow) and several intrahepatic branches (blue arrows). In the left flank pneumatotis intestinalis is seen in the obstructed small bowel loops. Portal gas in patients with bowel ischemiae has a very bad prognosis - life-threatening cause of PI. Page 18 of 24

19 Fig. 11: Additional sign: ascites. Pneumatosis intestinalis (yellow arrow) in a M. Kahler patient undergoing bone marrow transplantation. The segmental thickening of the bowel wall of the terminal ileum (curved blue arrow) in association with the mesenteric vascular engorgement (blue cross) and the diffuse ascites (red arrows), is very suggestive for Graft-versus-host disease - life-threatening cause of PI. Page 19 of 24

20 Fig. 12: Additional sign: arterial occlusion and free intraperitoneal air. CT of a patient with acute abdominal pain demonstrates absence of contrast in superior mesenteric artery, due to thrombosis of this vessel (red arrow). The small bowel ileus and free intraperitoneal air (yellow arrow) are very suggestive for small bowel ischemia complicated by perforation. When pneumoperitoneum is present, transmural intestinal necrosis should always be excluded first - life-threatening cause of PI. Page 20 of 24

21 Fig. 13: Pneumatosis intestinalis of the colon complicated by free intraperitoneal air. The patient was known with chronic obstructive lung disease and had no symptoms - benign cause of PI. Page 21 of 24

22 Conclusion Pneumatosis intestinalis is only a sign. The diagnosis of the underlying disease is important, as unnecessary surgery can be avoided in benign pneumatosis intestinalis, even when associtated with pneumoperitoneum. Page 22 of 24

23 Personal Information E. Vanhoutte, M. Lefere, R Vanslembrouck, D. Bielen, G. De Hertogh, A. Wolthuis, D. Vanbeckevoort. Department of Radiology. University Hospital Leuven, Herestraat 49, 3000 Leuven, Belgium. mail to:els.vanhoutte@uzleuven.be Page 23 of 24

24 References 1. Ho LM, Paulson EK, Thompson WM et al. Pneumatosis intestinalis in the adult: benign to life-threatening causes. AJR Am J Roentgenol 2007 ; 188 : Morris MS, Gee AC, Cho SD et al. Management and outcome of pneumatosis intestinalis. Am J Surg May; 195 : Page 24 of 24