Case Presentation A 47y WM s/ significant PMH presents to ED with a 2 week h/o abdominal pain. Pain is mostly in the LLQ, radiates across the abdomen, and has progressively worsened since onset. Patient reports pain is worse with standing and with po intake, denies any alleviating factors. Associated sx include nausea, vomiting, decreased po intake, and no BM in 2 weeks. Prior to this time he had normal formed BM daily. He has tried po and pr stimulation of BM s/ results. Prior to the onset of sx he denies BRBPR, melena, constipation, or bowel disease. PE: Abdomen distended, TTP throughout, > in LLQ. Guarding s/ significant rebound. Slightly decreased BS. WBC 21 w left shift

Left lateral decubitus and upright projections of the abdomen show mildly distended bowel loops. Case Presentation

CT abd/pelvis c/ contrast shows perforated sigmoid diverticulitis c/ free intraabdominal air. Case Presentation

Assessment: Likely diverticular disease of the sigmoid colon with micorperforation. Recommendation: X-lap and likely Hartmann's procedure Intraoperative Findings: Significantly inflamed and edematous sigmoid colon with a perforation noted on the left mid sigmoid. Postoperative Dx: Diverticulitis with perforation of the sigmoid colon Case Presentation

The Anatomical Basis of Diverticulosis

Introduction Diverticulum – a sac-like protrusion from a tubular or saccular organ Diverticulosis – presence of diverticula Diverticulitis – inflammation of diverticula Diverticular disease – term encompassing both diverticulosis and diverticulitis

Introduction Epidemiology Common, up to 65% by age 85 95% in sigmoid colon Risk factors Age, dietary fiber intake, gender, physical activity, obesity “Pseudodiverticula” Mucosa and submucosa herniate through muscle layer, covered only by serosa

Right colic (hepatic) flexure Left colic (splenic) flexure Transverse colon Ascending colon Descending colon Sigmoid colon Rectum Cecum Appendix Anal canal Anatomy of the Colon

Illustration by Donna Myers © 2007 Anatomy of the Colon

Meyers, MA

Anatomy of the Colon

Anatomic Basis of Disease Vasa recta Laplace Segmentation

Anatomic Basis of Disease Vasa Recta a) normal b) protrusion marking development of a diverticulum c) transmural extension

“Current Surgical Diagnosis and Treatment” Anatomic Basis of Disease Vasa Recta

Four distinct sites of formation: each side of the mesenteric taenia mesenteric border of the two antimesenteric taeniae

Anatomic Basis of Disease Vasa Recta

Anatomic Basis of Disease Law of Laplace P=kT/R : pressure P is proportional to wall tension T, and inversely proportional to bowel radius R

Anatomic Basis of Disease Segmentation Smooth muscle contraction separates colon into functionally distinct compartments

Summary Common disease that can lead to life threatening complications Pathophysiology directly related to anatomy: colonic structure, pressure and motility Eat your fiber!

References Heise CP Epidemiology and pathogenesis of diverticular disease. J Gastrointest Surg. Aug;12(8): Epub 2008 Feb 16. Kassahun WT, Fangmann J, Harms J, Bartels M, Hauss J Complicated small-bowel diverticulosis: a case report and review of the literature. World J Gastroenterol. Apr 21;13(15): Meyers, MA Dynamic Radiology of the Abdomen: Normal and Pathologic Anatomy. “The Colon: Normal and Pathologic Anatomy.” New York: Springer. Parra-Blanco A Colonic diverticular disease: pathophysiology and clinical picture. Digestion. 73 Suppl 1: Epub 2006 Feb 8. Petruzziello L, Iacopini F, Bulajic M, Shah S, Costamagna G Review article: uncomplicated diverticular disease of the colon. Aliment Pharmacol Ther. May 15;23(10): Sheth AA, Longo W, Floch MH Diverticular disease and diverticulitis. Am J Gastroenterol. Jun;103(6): Epub 2008 May 13. Woods K, Williams E, Melvin W, Sharp K Acquired jejunoileal diverticulosis and its complications: a review of the literature. Am Surg. Sep;74(9): Young-Fadok, T., and Pemberton, J.H. Clinical manifestations and diagnosis of colonic diverticular disease. UpToDate 2003.