Meckel’s Diverticulitis Case of the Month: October 2018 Claire Burrows, R2 McMaster University Di Muzio, B. & Jha, P. (2018) Meckel diverticulitis. Radiopedia. Retrieved September 30, 2018 from https://radiopaedia.org/articles/meckel-diverticulitis-1

Case Presentation 65 M presents to the ER: Chief Complaint: RLQ pain x 2 days, rule out appendicitis vs. diverticulitis Past Medical/Surgical History: Otherwise well, no prior abdominal surgeries Investigations: Labs: elevated WBC count Imaging: CT Abdo/Pelvis C+ Wang, W. (2018). Radiology Case: Meckel diverticulitis. Radiopaedia. Retrieved September 30, 2018 from https://radiopaedia.org/cases/meckel-diverticulitis-5

No evidence of appendicitis or colonic diverticulitis on CT Di Muzio, B. & Jha, P. (2018) Meckel diverticulitis. Radiopedia. Retrieved September 30, 2018 from https://radiopaedia.org/articles/meckel-diverticulitis-1 Wang, W. (2018). Radiology Case: Meckel diverticulitis. Radiopaedia. Retrieved September 30, 2018 from https://radiopaedia.org/cases/meckel-diverticulitis-5

In the RLQ there is fat stranding associated with a tubular, blind-ending structure favoured to be arising from the small bowel. Wang, W. (2018). Radiology Case: Meckel diverticulitis. Radiopaedia. Retrieved September 30, 2018 from https://radiopaedia.org/cases/meckel-diverticulitis-5

There is suspected perforation. No drainable collection identified. Wang, W. (2018). Radiology Case: Meckel diverticulitis. Radiopaedia. Retrieved September 30, 2018 from https://radiopaedia.org/cases/meckel-diverticulitis-5

Findings in keeping with perforated Meckel’s diverticulitis Findings in keeping with perforated Meckel’s diverticulitis. OR confirmed this. Wang, W. (2018). Radiology Case: Meckel diverticulitis. Radiopaedia. Retrieved September 30, 2018 from https://radiopaedia.org/cases/meckel-diverticulitis-5

Pathophysiology of Meckel’s Diverticulum Most common congenital anomaly of GI tract (2% population) Remnant of vitelline/omphalomesenteric duct that connects yolk sac with primitive midgut Vitelline duct should normally be obliterated between 8-10 weeks gestation There may be a fibrous band connecting the Meckel’s diverticulum to the umbilicus Gulwani, H. (2018 February 9). Meckel diverticulum. PathologyOutlines.com. Retrieved September 30th, 2018 http://www.pathologyoutlines.com/topic/smallbowelMeckels.html Kuwajerwala, N.K. & Silva, Y. J. (2017, April 11). Meckel Diverticulum. Medscape. Retrieved September 30, 2018 from https://emedicine.medscape.com/article/194776-overview#a1

It is a true diverticulum (contains all layers of bowel wall) Located on antimesenteric border of ileum, 1-8 cm long, 20 cm proximal to ileocecal valve May contain gastric, pancreatic, duodenal, colonic or even biliary mucosa Usually contains intestinal mucosa, but 50% have gastric or pancreatic heterotopia Remember these details by “Rule of 2’s”: Affects 2% of the population 2:1 M:F ratio Patients often present by 2 years of age Found within 2 feet of ileocecal valve 2 inches in length and 2 inches in diameter Symptomatic in 2% of cases Often 2 types of tissue found: gastric and pancreatic Gulwani, H. (2018 February 9). Meckel diverticulum. In PathologyOutlines.com. Retrieved September 30th, 2018 http://www.pathologyoutlines.com/topic/smallbowelMeckels.html

Patient’s with Meckel’s Diverticulum can present in multiple ways: Bright red blood per rectum 40% Meckel complications occur in children <10 years old: GI bleeding most common Inflammation (10-20%)/perforation Small bowel volvulus Bowel obstruction (20-25%) Adults more prone to obstructions Meckel’s can act as lead point for intussusception Littre’s hernia (incarcerated Meckel’s in inguinal canal) Neoplasm (4-5%) Gulwani, H. (2018 February 9). Meckel diverticulum. PathologyOutlines.com. Retrieved September 30th, 2018 http://www.pathologyoutlines.com/topic/smallbowelMeckels.html Hartung, Michael. (2018). Radiology CaseL Meckel diverticulitis. In Radiopaedia. Retrieved September 30, 2018 from https://radiopaedia.org/cases/meckel-diverticulitis-7

EXAMPLE: Imaging: Meckel’s causing SBO; Intraoperative Findings: gangrenous torted Meckel’s Cartanese C, Petitti T, Marinelli E, Pignatelli A, Martignetti D, Zuccarino M, Ferrozzi L. Intestinal obstruction caused by torsed gangrenous Meckel’s diverticulum encircling terminal ileum. World J Gastrointest Surg 2011; 3(7): 106-109

Lifetime risk of complication requiring surgery: 6.4% Diagnosing a Meckel’s as the cause of these presentations can be challenging based on imaging: for example, case below: negative nuclear medicine scan, OR findings positive for Meckel’s Gulwani, H. (2018 February 9). Meckel diverticulum. PathologyOutlines.com. Retrieved September 30th, 2018 http://www.pathologyoutlines.com/topic/smallbowelMeckels.html Hartung, M. (2018). Radiology Case: Meckel diverticulitis. Radiopaedia. Retrieved September 30, 2018 from https://radiopaedia.org/cases/meckel-diverticulitis-7 Kuwajerwala, N.K. & Silva, Y. J. (2017, April 11). Meckel Diverticulum. Medscape. Retrieved September 30, 2018 from https://emedicine.medscape.com/article/194776-overview#a1

Imaging Asymptomatic Upper GI series with Small Bowel follow through findings: blind-ending loop filled with contrast on antimesenteric border of ileum, 50 cm proximal to IC valve Fukushima, Masashi & Kawanami, Chiharu & Inoue, Satoko & Okada, Akihiko & Imai, Yukihiro & Inokuma, Tetsuro. (2014). A case series of Meckel's diverticulum: Usefulness of double-balloon enteroscopy for diagnosis. BMC gastroenterology. 14. 155. 10.1186/1471-230X-14-155.

Technetium-99m pertechnetate radioisotope scan Symptomatic Technetium-99m pertechnetate radioisotope scan radioisotope taken up by gastric mucosa need approximately 1.8 cm2 of ectopic gastric mucosa to see positive result negative scan does not exclude Meckel’s diverticulum Radswiki. (2018). Radiology Case: Meckel diverticulum. Radiopaedia. Retrieved September 30, 2018 from https://radiopaedia.org/cases/meckel-diverticulum

Symptomatic CT SMA angiography Treatment Surgery For acute GI bleeding when blood loss >0.5 mL/min Treatment Surgery Wikipedia contributors. (2015, November 10). “Angiography of a Meckel’s diverticulum that presented with bleeding.jpg.” Wikipedia, The Free Encyclopedia. Retrieved September 30, 2018, from https://wikivisually.com/wiki/File:Angiography_of_a_Meckel%27s_diverticulum_that_pres ented_with_bleeding.jpg

References Cartanese C, Petitti T, Marinelli E, Pignatelli A, Martignetti D, Zuccarino M, & Ferrozzi L. (2011). Intestinal obstruction caused by torsed gangrenous Meckel’s diverticulum encircling terminal ileum. World J Gastrointest Surg, 3(7): 106-109 Kuwajerwala, N.K. & Silva, Y. J. (2017, April 11). Meckel Diverticulum. Medscape. Retrieved September 30, 2018 from https://emedicine.medscape.com/article/194776-overview#a1 Di Muzio, B. & Jha, P. (2018) Meckel diverticulitis. Radiopedia. Retrieved September 30, 2018 from https://radiopaedia.org/articles/meckel-diverticulitis-1 Fukushima, Masashi & Kawanami, Chiharu & Inoue, Satoko & Okada, Akihiko & Imai, Yukihiro & Inokuma, Tetsuro. (2014). A case series of Meckel's diverticulum: Usefulness of double-balloon enteroscopy for diagnosis. BMC gastroenterology, 14. 155. 10.1186/1471-230X-14-155. Gulwani, H. (2018, February 9). Meckel diverticulum. PathologyOutlines.com. Retrieved September 30, 2018 from http://www.pathologyoutlines.com/topic/smallbowelMeckels.html

References continued Hartung, M. (2018). Radiology Case: Meckel diverticulitis. Radiopaedia. Retrieved September 30, 2018 from https://radiopaedia.org/cases/meckel-diverticulitis-7 Radswiki. (2018). Radiology Case: Meckel diverticulum. Radiopaedia. Retrieved September 30, 2018 from https://radiopaedia.org/cases/meckel-diverticulum Wang, W. (2018). Radiology Case: Meckel diverticulitis. Radiopaedia. Retrieved September 30, 2018 from https://radiopaedia.org/cases/meckel-diverticulitis-5 Wikipedia contributors. (2015, November 10). Angiography of a Meckel’s diverticulum that presented with bleeding.jpg. Wikipedia, The Free Encyclopedia. Retrieved September 30, 2018, from https://wikivisually.com/wiki/File:Angiography_of_a_Meckel%27s_diverticulum_that_presented_with_bleeding.jpg