DIVERTICULAR DISEASE HANDS OFF OR HANDS ON?

DIVERTICULAR DISEASE HANDS OFF OR HANDS ON? TE MADIBA AND M NAIDOO TE MADIBA MMed, LLM, PhD, FCS (SA), FASCRS Emeritus Professor of Surgery & Director of the Gastrointestinal Cancer Research Centre, University of KwaZulu-Natal, Durban M NAIDOO MBChB, FCS (SA), Cert Surg Gastro Colorectal Surgeons, UKZN Teaching Hospitals & University of KwaZulu-Natal, Durban HIGHLIGHTS 1. The initial evaluation should include a problem-specific history and physical examination, as well as CT scan of the abdomen and pelvis. 2. Non-operative treatment typically includes oral or intravenous antibiotics and image-guided percutaneous drainage for (Hinchey Grade II). 3. Urgent sigmoid colectomy is required for patients with diffuse peritonitis or following failure of non-operative management. 4. Evaluation after recovery from acute diverticulitis should be by colonoscopy. 5. Elective surgery should be individualised and should not be based on age. 6. GI bleeding occurs in 15% and is usually painless and self-limiting. It seldom requires surgery. INTRODUCTION Diverticular disease is common and thought to result from structural abnormalities of the colonic wall, disordered intestinal motility and deficiencies in dietary fibre. DEFINITIONS A diverticulum is an acquired herniation of the mucosa, creating a pouch-like protrusion through the colonic muscle wall. The term diverticulosis describes the presence of diverticula; the condition can be asymptomatic.

Diverticulitis is the clinical syndrome associated with an inflamed diverticulum; it may be associated with local perforation and peri-colitis. The term diverticular disease includes diverticulosis and diverticulitis and encompasses all manifestations, including the muscular abnormalities in the colonic wall that usually accompany diverticulosis. EPIDEMIOLOGY Diverticular disease is a common gastrointestinal disorder, with an age-dependent prevalence of 5-45% with up to 30% of the population over the age of 60 having evidence of diverticulosis 1,2. About 80-85% of the people with this condition are asymptomatic. Of the 15-25% symptomatic patients, 75% will have painful diverticular disease without inflammation, and 25% will suffer an acute attack. Of the patients with diverticulitis, 30% will develop complicated diverticular disease. Gastrointestinal haemorrhage in diverticular disease occurs in in 5-15% 1,2. PATHOLOGICAL ANATOMY Colonic diverticula typically form in parallel rows between the taeniae coli because of weakness of the muscular wall at sites of penetration of the vasa recta supplying the mucosa 1,2. Diverticula vary from solitary findings to many hundreds. They are typically 5-10mm in diameter but can exceed 2cm. In the Western world diverticula arise mainly in the distal colon, with 90% of patients having sigmoid colon involvement and only 15% having right-sided diverticula 1,2. This finding is in contrast to Asian populations, in which right-sided involvement is more prominent 1,2. PATHOGENESIS The development of diverticulosis is a result of disordered motility, related to higher resting, postprandial, and neostigmine-stimulated intra-luminal pressures. This dysmotility is due to segmentation, in which contraction of the colon causes a series of discrete little bladders. This segmentation delays transport and augments water reabsorption but can also generate excessively high pressures within every bladder, facilitating herniation. This effect might be amplified by dietary fibre deficiency.

Diverticula arise as a result of an increase in colonic wall resistance to this high pressure, leading to muscular thickening and shortening of the taeniae coli, with resultant concertina-like bunching of haustral folds 1,2. Elastin deposition is amplified by more than 200% in muscle cells in the taeniae coli compared to segment without diverticula. Consequently, patients with symptomatic diverticulosis have been shown to have higher motility indices than either asymptomatic patients or healthy controls. CLINICAL PICTURE The clinical presentation of diverticular disease ranges from asymptomatic diverticulosis, diverticulosis with periodic spasmodic abdominal pain and bloating, diverticulosis with haemorrhage, and finally diverticulitis 3. Chronicity occurs in a large proportion of patients and includes chronic, non-relenting, low-level symptoms, typically located in the left lower quadrant 3. These symptoms constitute diverticulosis. Patients with this chronic symptoms have favourable long-term outcomes, but impaired quality of life 3. These symptoms may suggest chronic inflammation and some patients may benefit from treatment with anti-inflammatory medications. For this reason this condition is often confused with irritable bowel syndrome. Diverticulitis Micro-perforation of the diverticulum usually initiates the inflammatory process leading to localised inflammation in the colonic wall or peri-colic tissues 4. Infection limited to a tiny diverticulum may not cause symptoms. When such infection extends through the wall of the diverticulum into the peridiverticular tissues (peri-diverticulitis) it becomes clinically significant 4. The pericolitis extends around the diverticulum and dissects into the immediately adjacent peri-colic fat. Further extension of the infection may lead to peri-colic abscess, sinus tracts, pelvic abscess and peritonitis. Over time the numerous foci of inflammatory reaction may cause fibrotic thickening in the colonic wall 4.

There are a number of ways of classifying diverticulitis clinically. The clinical classification devised by the European Association for Endoscopic Surgeons (EAES) is the most commonly used (Table 1). The severity of complicated diverticulitis has been classified into four grades according the Hinchey classification 3. The modified Hinchey classification is shown in Table 2. The limitation of the Hinchey classification is its failure to address the long-term complications such as stricturing and fistulisation. Table 1. EAES Clinical Classification f Diverticular Disease (Adapted from Kohler et al 13 ) Grade Description Clinical parameters I Symptomatic, uncomplicated disease Fever, crampy abdominal pain II Recurrent, symptomatic disease Recurrence of above III Complicated disease Complications * * Complications include: abscess, phlegmon, fistula, perforation, stricture, and peritonitis Table 2. Modified Hinchey Classification (Adapted from Sheth et al [3] ) Grade Description 0 Mild clinical diverticulitis Ia Ib II III IV Confined peri-colic inflammation or phlegmon Peri-colic or mesocolic abscess Pelvic, distant intra-abdominal, or retroperitoneal abscess Generalised purulent peritonitis Generalised faecal peritonitis Abscess formation and peritonitis Micro-perforation results in more extensive bacterial contamination and more serious infection leading to abscess formation or peritonitis 4. Uncommonly the diverticulum may rupture into the free peritoneal cavity due to the excessively high intraluminal pressure 4. CLINICAL EVALUATION The initial evaluation of a patient with suspected acute diverticulitis should include a problem-specific history and physical examination, a complete blood count, urinalysis, and abdominal radiographs.

CT scan of the abdomen and pelvis is the most appropriate and reliable initial imaging modality in the assessment of suspected diverticulitis 5. CT scans enhanced with intravenous and intra-rectal contrast has replaced contrast enema with a sensitivity and specificity of up to 100%. It can demonstrate the presence of an abscess and assess the feasibility of direct percutaneous drainage 6. In the case of diverticular bleeding, a contrast CT scan (CT angiography) may demonstrate a contrast blush, provided there is on-going blood loss of at least 2ml/min 6. Colonoscopy is indicated when there is doubt about cancer, persisting or recurrent complaints in the left lower quadrant, and suspicion of a stenosis or recurrent blood loss. Colonoscopy enables biopsies for histological diagnosis, and cessation of diverticular bleeding may be attempted by endoscopic measures 6. MANAGEMENT Medical Treatment of Acute Diverticulitis Non-operative treatment typically includes oral or intravenous antibiotics and diet modification. Image-guided percutaneous drainage is usually the most appropriate treatment for stable patients with large diverticular abscesses. (Hinchey Grade II) 5. Surgical intervention is rarely indicated in cases of acute diverticulitis because most of these cases will resolve with appropriate antibiotic management. Emergency Surgery for Acute Diverticulitis Surgery is reserved for cases of complicated diverticulitis, such as perforation and peritonitis, abscess formation, obstruction and fistula formation or for failure of nonoperative management 5,8. Although this may seem clear-cut, decisions regarding if and when to operate remain a topic of debate 8. Urgent surgery in the form of sigmoid colectomy is clearly indicated when the patient presents with perforation and diffuse peritonitis, whether purulent or feculent (Hinchey stages III and IV) 5,8. Technical Considerations Following colonic resection for perforated sigmoid colon diverticulitis, the decision to restore bowel continuity must incorporate patient factors, intraoperative factors, and surgeon preference 5.

The low mortality and morbidity of a primary anastomosis suggests that a one-stage procedure can be safely performed, given meticulous surgical technique by an experienced surgeon 7. The presence of local or even diffuse faecal peritonitis does not preclude a primary anastomosis if an extensive intraoperative lavage is performed 7. Laparoscopic lavage combined with intravenous antibiotics without sigmoid resection in patients with purulent peritonitis caused by complicated diverticulitis has a low morbidity rate, low mortality, shorter operation time, shorter hospital stay and lower economic costs 9,10,11. It could be considered a valid and preferable alternative to more radical procedures, including the Hartmann s procedure 11. Subsequent elective resection is probably unnecessary and readmission in the medium term is uncommon 9. Evaluation after Recovery from Acute Diverticulitis After resolution of an episode of acute diverticulitis, the colon should typically be evaluated endoscopically to confirm the diagnosis and rule out malignancy, where it is a first episode or no recent colonoscopy has been performed 5,6. Recurrent Diverticulitis Approximately 25% of patients will suffer more than one attack of acute diverticulitis. Although previous studies have suggested recurrent diverticulitis was a more virulent disease, with subsequent attacks being more likely to fail medical therapy and require emergency surgery, recent evidence suggests otherwise 3. The American Society of Colon and Rectal Surgeons amended their previous guidelines by commenting report that The decision to recommend elective colectomy after recovery from acute diverticulitis should be made on a case-by-case basis 5. Elective Surgery for Acute Diverticulitis There is now overwhelming evidence to challenge the practice of elective sigmoid resection following two attacks of diverticulitis.

Prophylactic resection will not decrease the risk of emergency surgery in patients with mild diverticulitis, as the majority of patients require emergency intervention on the first admission 12. The natural history of mild diverticulitis is that it runs an uncomplicated course and patients treated conservatively are at low risk of developing severe diverticular disease 12. In addition, elective resection does not completely prevent recurrent diverticulitis and carries significant morbidity and mortality. Moreover it is not the most cost-effective solution 12. The decision for elective sigmoid colectomy after complicated acute diverticulitis is questioned. If elective surgery is considered, it is suggested that it be done after the patient has completely recovered 5. The extent of elective resection should include the entire sigmoid colon with margins of healthy colon and rectum 5. When expertise is available the laparoscopic approach, which technically more difficult, is preferred 5. A leak test of the colorectal anastomosis should be performed during surgery for sigmoid diverticulitis. Oral mechanical bowel preparation is not required; however, the use of prophylactic antibiotics may decrease surgical site infections after elective colon resection 5. Young Patients There is an increasing incidence of diverticular disease in young patients 3. Whereas it has historically been thought of as a more virulent disease in the young, recent data suggest that that any increased risk appears to be a chronological rather than a pathological phenomenon and that most young patients will not have further episodes of diverticulitis 5. Thus routine elective resection based on young age is no longer recommended 5.

Segmental Colitis or Sigmoid Colitis-Associated Diverticular Disease Segmental colitis or sigmoid colitis-associated diverticular disease (SCADD) is a unique form of chronic colitis limited to areas of the colon with diverticular formation 3. Often mistakenly diagnosed as ulcerative colitis or Crohn s disease, patients present with pain and intermittent rectal bleeding. Colonoscopic evaluation reveals friable mucosa in the region of diverticular disease, with a notable absence of aphthous ulcerations typically found in Crohn s disease 3. The inflammatory reaction is characterised by focal chronic colitis without granulomas and characteristically involves the inter-diverticular colonic mucosa, sparing the diverticula themselves 3. Studies have shown benefit to both medical therapy with antibiotics and 5-aminosalicylic acid (5-ASA) compounds as well as surgical resection 3. Immuno-compromised Patients Prevalence of diverticulitis is not increased in immunocompromised patients; however, there is evidence to suggest that episodes of diverticulitis are more likely to be complicated 3. The clinical presentation is further complicated by the often indolent, smouldering nature of acute episodes of diverticulitis and the lack of the usual signs of the disease such as fever and elevated white blood cell count 3. Despite this there is no clear evidence for aggressive surgical management of simple diverticulitis in these patients 3. GASTROINTESTINAL HAEMORRHAGE Per-rectal bleeding occurs in 15% of patients with diverticulosis, resulting from injury to the vasa recta as they are exposed over the dome of the diverticulum 6. The bleeding is usually painless, self-limiting, and rarely co-exists with diverticulitis. In one-third of patents with diverticular haemorrhage massive bleeding occurs and tends to be sudden and profuse 6. Two thirds of haemorrhages are from the right side of the colon 6.

Rectal bleeding settles spontaneously in 80-85% 6. Endoscopic evaluation is the examination of choice for diagnosis and treatment. Colonoscopic haemostatic techniques, with clinical success rates of 70-100%, include: adrenaline (epinephrine) injection, bipolar coagulation and clipping 6. When endoscopic techniques fail, angiographic trans-arterial embolisation is recommended. Surgery can be considered if other modalities fail 6. CONCLUSION Most episodes of diverticulitis and diverticular haemorrhage can be successfully managed non-operatively. Surgery is reserved for complicated diverticulitis and failed conservative management of diverticular haemorrhage. REFERENCES 1. Stollman N, Raskin JB. Diverticular disease of the colon. Lancet 2004; 363: 631-39. 2. Matrana MR, Margolin DA. Epidemiology and Pathophysiology of Diverticular Disease. Clin Colon Rectal Surg 2009;22: 141-146. 3. Sheth AA, Longo W, Floch MH. Diverticular Disease and Diverticulitis. Am J Gastroenterol 2008;103: 1550-1556. 4. Dayal Y, DeLellis RA. The Gastrointestinal tract. In Cotran RS, Kumar V, Robbins SL, Eds, Robbins Pathological Basis of Disease 827-910, 1989, WB Saunders, London. 5. Feingold D, Steele SR, Lee S, et al. Practice Parameters for the Treatment of Sigmoid Diverticulitis. Dis Colon Rectum 2014; 57(3): 284-294. 6. Klarenbeek BR, de Korte N, van der Peet DL, Cuesta MA. Review of current classifications for diverticular disease and a translation into clinical practice. Int J Colorectal Dis 2012; 27:207-214. 7. Schilling, MK, Maurer CA, Kollmar O, Bfichler MW. Primary vs. Secondary Anastomosis After Sigmoid Colon Resection for Perforated Diverticulitis (Hinchey Stage III and IV). A Prospective Outcome and Cost Analysis. Dis Colon Rectum 2001;44:699-705. 8. Bordeianou L Hodin R. Controversies in the Surgical Management of Sigmoid Diverticulitis. J Gastrointest Surg 2007; 11:542-548. 9. Myers E, Hurley M, O Sullivan GC, Kavanagh D, Wilson I, Winter DC. Laparoscopic peritoneal lavage for generalised peritonitis due to perforated diverticulitis. Br J Surg 2008; 95: 97-101. 10. Alamili M, Gögenur I, Rosenberg J. Acute Complicated Diverticulitis Managed by Laparoscopic Lavage. Dis Colon Rectum 2009; 52: 1345-1349.

11. Karoui M, Champault A, Pautrat K, Valleur P, Cherqui D, Champault G. Laparoscopic Peritoneal Lavage or Primary Anastomosis With Defunctioning Stoma for Hinchey 3 Complicated Diverticulitis: Results of a Comparative Study. Dis Colon Rectum 2009; 52: 609-615. 12. Collins D, Winter DC. Elective Resection for Diverticular Disease: An Evidence-Based Review. World J Surg 2008; 32: 2429-2433. 13. Kohler L, Sauerland S, Neugebauer E. Diagnosis and treatment of diverticular disease: Results of a consensus development conference. The scientific committee of the European Association of Endoscopic Surgery. Surg Endosc 1999; 13:430-6.