|Year : 2013 | Volume
| Issue : 2 | Page : 226-231
Presentation, distribution pattern, and management of diverticular disease in a Nigerian tertiary hospital
OI Alatise1, AO Arigbabu1, OO Lawal1, VA Adetiloye2, EA Agbakwuru1, DA Ndububa3
1 Department of Surgery, College of Health Sciences, Obafemi Awolowo University, Ile-Ife, Osun State, Nigeria
2 Department of Radiology, College of Health Sciences, Obafemi Awolowo University, Ile-Ife, Osun State, Nigeria
3 Department of Medicine, College of Health Sciences, Obafemi Awolowo University, Ile-Ife, Osun State, Nigeria
|Date of Acceptance||27-May-2012|
|Date of Web Publication||6-Apr-2013|
O I Alatise
Department of surgery, Obafemi Awolowo University Teaching Hospital Complex, PMB 5538, Ile-Ife, Osun State. 220005
Source of Support: None, Conflict of Interest: None
| Abstract|| |
Background: Colonic diverticular disease is one of the most common and costly gastrointestinal disorders among industrialized societies, which have recently been described among Africans. Presentations and distribution pattern of the disease among Africans appeared to be different from that described among the Western population. We embark on this study aimed at evaluating the presentation, distribution pattern, and the management of diverticulosis in our tertiary health facility.
Materials and Methods: A prospective descriptive study of the cases of diverticular disease seen between January 2007 and December 2011 at Obafemi Awolowo University Teaching Hospitals Complex, Ile-Ife, Osun State, Nigeria.
Results: During the 5-year study period, 40 cases were seen. The patients were aged 41-85 years with a median age of 64 years. There were 29 (72.5%) male and 11 (27.5%) female with an average male to female ratio of 3:1. The most common presentation was bleeding per rectum in 28 (70%) patients, which mostly needed transfusion. Ten (25%) patients presented with recurring abdominal pain, whereas one (2.5%) patient presented with abdominal mass and features of intestinal obstruction. Thirty patients were diagnosed on colonoscopy, eight on barium enema, and two on computerized tomography scan. Thirty-four (85%) patients had a pancolonic disease. All the patients were placed on high fiber diet and antibiotics namely ciprofloxacin and metronidazole. Five patients had recurrence within 6 months of follow up, of which one had emergency colectomy.
Conclusion: Diverticular disease is no longer a rare disease in Nigeria. It is a common cause of lower gastrointestinal bleeding in elderly patients. High index of suspicion for diverticular disease of the colon and its complications should increase in the country.
Keywords: Distribution pattern, diverticular disease, management, Nigeria, presentation
|How to cite this article:|
Alatise O I, Arigbabu A O, Lawal O O, Adetiloye V A, Agbakwuru E A, Ndububa D A. Presentation, distribution pattern, and management of diverticular disease in a Nigerian tertiary hospital. Niger J Clin Pract 2013;16:226-31
|How to cite this URL:|
Alatise O I, Arigbabu A O, Lawal O O, Adetiloye V A, Agbakwuru E A, Ndububa D A. Presentation, distribution pattern, and management of diverticular disease in a Nigerian tertiary hospital. Niger J Clin Pract [serial online] 2013 [cited 2020 Jul 4];16:226-31. Available from: http://www.njcponline.com/text.asp?2013/16/2/226/110152
| Introduction|| |
Colonic diverticular disease, one of the most common and costly gastrointestinal disorders among industrialized societies, is characterized by the formation of sac-like outpouchings or pockets within the colon that form when colonic mucosa and submucosa herniate through weakened areas in the muscle layer (pseudo-diverticula). ,, It occurs at the point of entry of the small arteries that supply the colon, the vasa recta, penetrate the circular muscle layer of the colonic wall. , These entry points of the vasa recta are areas of relative weakness through which the mucosa and sub mucosa can herniate when under increased intraluminal pressure. ,,
One of the unique aspects of diverticular disease is its considerable geographic variation. ,, The prevalence, anatomical location, and presentation of diverticular disease have different characteristics depending on the regional, racial, and dietary factors.  The disorder is extraordinarily rare in rural Africa and Asia; conversely, the highest incidence rates are seen in the United States, Europe, and Australia.  A Nigerian review of 603 adult barium enema examinations demonstrated only 11 cases of diverticular disease, which account for less than 2% of cases.  A report from southern Islamic Republic of Iran noted a 1.2% incidence in more than 500 barium enema studies.  These data contrast sharply with the incidence of 42-54% in the Western populations.  The marked difference in the disease prevalence was speculated to be due to some genetic factors, dietary or other unseen environmental factors, which may play a role in protecting native Africans. ,
The anatomical location of diverticular in the Asian populations tends to be right-sided, in contrast to American, European, and Australian series, which show a left-sided predominance.  Few African studies from Durban in South Africa, Ghana, and Uganda also suggested preponderance of right-sided diverticula among African population. ,,, In view of the rarity of the disease and that there have been no characterization of the location of diverticular disease in Nigeria, we embark on this study aimed at evaluating the presentation, distribution pattern, and the management of diverticulosis in our tertiary health facility.
| Materials and Methods|| |
The study was carried out at the Obafemi Awolowo University Teaching Hospitals Complex (OAUTHC), Ile-Ife, Osun State. The hospital provides tertiary level services being mostly accessed by patients from Osun, Ondo, Ekiti, and some parts of Kwara, Kogi, Oyo, and Edo States with an estimated population of about 10 million according to 2006 National population census.
The people Ife/Ijesa zone of Osun State where the institution is located are predominantly Yorubas, who along with other Nigerian tribes and other ethnic groups, however, also reside permanently in this area. Peasant farming is the major occupation of the people. A sizeable number are engaged in commercial and small-scale industrial enterprises, whereas the cream of the educated ones are the civil servants.
This is a prospective study of all cases of colonic diverticular disease diagnosed on barium enema, contrast enhanced computerized tomography (CT) scan, and/or colonoscopy between January 2007 and December 2011. Information obtained from each patient included sociodemographic data such as sex, age, occupation, and socioeconomic status. Other information obtained included co-morbidity, presenting symptoms, presence of pyrexia on admission, method of diagnosis, clinical investigations, distribution pattern of the diverticular disease within the colon, management and management outcome, duration of follow-up, and recurrent episodes.
Definition of terms
Because symptoms, colonoscopy, and radiographic findings do not always distinguish between diverticulosis and diverticulitis, the more general term, diverticular disease of the colon, is used.
The terms 'diverticulosis' and 'diverticular disease' are used to describe the presence of uninflamed diverticula. Diverticulitis is an inflammatory complication of the disease, which is commonly accompanied by gross or microscopical perforation, ranging in severity from a single, mild, acute attack of diverticulitis to more severe attacks characterized by perforation and abscess formation, occasionally resulting in chronic complications such as obstruction and fistula formation. 
All data were entered into the personal computer and analyses were performed using SPSS version 16.0. Descriptive and inferential statistics were used in the analysis of the data.
| Results|| |
During the 5-year study period, 40 patients were diagnosed to have diverticular disease at OAUTHC, Ile-Ife, Osun state, Nigeria. The patients were aged 41-85 years with a median age of 64 years. The peak age is in the eight decade [Figure 1]. Only five (12.5%) of the patients were aged ≤50 years. There were 29 (72.5%) male and 11 (27.5%) female with an average male to female ratio of 3:1.
All the patients had various levels of education. Three (7.5%) patients had educational level only up to primary school, whereas eight (20%) patients had educational level up to secondary school level, and others (72%) had higher education in tertiary level institutions. The types of occupation the patients were engaged is varied. Among the male patients, 8 (27.6%) were 'businessmen' or traders, 7 (24.1%) patients were farmers, 5 (17.2%) were retirees, 5 (17.2%) artisans, 2 (6.9%) professors of social sciences, 1 (3.5%) surgeon, and 1 (3.5%) engineer. Among the female patients, 6 (54.6%) were retirees or grandmothers who were just 'staying at home', 3 (27.3%) had their own businesses mainly selling goods at a market or roadside, and 1 (9%) was a principal of a private school. Only 5 of 40 patients gave history of intake of westernized diet as they reside in developed countries for significant number of years. Essentially, majority of the patients eat traditional mixed diet.
The most common presentation was bleeding per rectum in 28 (70%) patients. The bleeding was severe necessitating hospital admission and blood transfusion in 20 of the 28 patients. The number of blood transfused ranged from 2 to 8 with a median of 4. Ten (25%) patients presented with recurring abdominal pain, whereas one (2.5%) patient presented with abdominal mass and features of intestinal obstruction. Similarly, 8 of 10 patients with abdominal pain had fever at presentation. Thirty-two (80%) patients were admitted into the hospital for treatment of the disease.
The body mass index (BMI) of the patients ranged from 22.5 to 40.8 kg/m 2 . The median BMI was 32.6 kg/m 2 . Whereas majority (25 of 28) of the patients who presented with bleeding per rectum had their BMI greater than 25 kg/m 2 , all the patients who presented with abdominal pain had their BMI less than 25 kg/m 2 . Of the 40 patients, 8 patients had associated hypertension and are on combination of antihypertensive and aspirin. All these patients presented with bleeding per rectum.
Colonoscopy was performed on 30 patients [Figure 2], whereas 8 patients had barium enema [Figure 3], and 2 had the diagnosis made on CT scan. Other findings on colonoscopy included internal hemorrhoids in 8 patients and polyps in 3 patients. In 34 of the 40 patients, the diverticulosis was found in every part of the colon. It was found on the right side of the colon and the transverse colon in 4 of the 40 patients whereas only 2 of the 40 patients had the diverticulosis restricted to the left colon.
|Figure 2: Colonoscopic finding of a 65-year-old man with diverticular disease|
Click here to view
|Figure 3: The barium enema of a 68-year-old woman with diverticular disease|
Click here to view
All the patients were placed on high fiber diet and antibiotics namely ciprofloxacin 500 mg twice daily and metronidazole 400 mg thrice daily for at least 10 days. All of them responded to conservative managements. Those on hospital admission were discharged. Five patients had recurrence of the symptoms within 6 months of treatment-bleeding per rectum in four patients and abdominal pain in one patient. Among those that had re-bleeding per rectum, the bleeding was torrential necessitating emergency colectomy in one patient. Others declined surgery.
All the patients that had re-bleeding were aged above 65 years with poor compliant to the drug treatment. Three of these patients had associated elevated blood pressures that are also on low dose aspirin. The other two patients were obese. No other colonic lesion seen in these patients that may be responsible for the re-bleeding. The re-bleeding occurred at a variable period of 2 and 6 months after completing the treatment.
| Discussion|| |
In the past century, diverticular disease was unknown among African descend.  Recently, however, it has been reported that diverticular disease of the colon is on the rise in the African population. ,,, Madiba reported 26 cases in a period of 5 years in South African Blacks.  Kiguli-Malwadde and Kasozi reported 31 cases in 5 years among the Ugandians.  Baako reported 37 cases over 3 years in Ghana.  In Nigeria, few cases of diverticular disease had been presented. Ogunbiyi in Ibadan presented 11 cases from 603 barium enema performed at University College Hospital.  Similarly, Ihekwaba also reported 15 cases of colonic diverticular disease managed in the same hospital and about the same period.  We present 40 cases of diverticular disease managed over a short time of 5 years. This supports the fact that more cases of diverticular disease are being seen in the African population.
The reason for the apparent surge in the occurrence of diverticulosis is not known. Diverticular disease is a disease of the aging population ,, and in contrast to a report by Ihekwaba  in Ibadan who found that more than 70% of their patients were aged below 50 years; more than 75% of our patients were aged above 50 years. The median age of our patients was similar to those reported from the Western population.  It is possible that the previous rarity of diverticular disease in Nigeria may be due to the reduced life expectancy in the country. With gradual improvement in the life expectancy and the health care in most African countries, more cases of diverticular disease will be diagnosed.
Up to now, there is no clear predisposition to diverticular disease on the basis of sex.  In this study, we found that males were affected three times more than women. Madiba reported female predilection among South African Blacks,  Kiguli-Malwadde and Kasozi showed no sex predilection among Ugandian cohort.  A study from Singapore showed that diverticula were seen more frequently in men than women (20.1% vs. 17.2%).  Eide and Stalsburg in Norway reported 280 unselected autopsies in patients aged above 20 years and found an incidence of 25% in males and 43% in females.  The true sex distribution is difficult to determine because most patients with the condition are asymptomatic.  Symptomatic diverticular disease, however, is more easily studied, and more data are available in these groups. Patients aged above 50 years and hospitalized for diverticular disease in a large Canadian study were more frequently female, and this preponderance increased with increase in age. However, men aged below 50 years were hospitalized more frequently than women, suggesting both age and sex effects on the development of symptomatic disease. 
The evaluation of our patient's socioeconomic status showed that all social strata were affected by the disease and only few patients gave history of intake of refined food. Essentially majority of our patients consume more of local high fiber diet. It was previously suggested that the current emergence of diverticular disease in our environment may be due to change in diet. , No doubt, there is a recent increase in 'fast food joints' in Nigeria; most of this refine food may be beyond the reach of majority of our patients. Other factors other than diet may be responsible for the increase occurrence of diverticular disease in Africans. Omojola et al., in Port-Harcourt, reported a cases series of three siblings, all having diverticular disease.  Similarly, Schlotthauer reported seven cases of diverticular disease in a family of nine siblings presenting between 49 and 70 years of age.  These reports underscore the fact that some genetic factors may play a role in the occurrence of diverticular disease among the African population. In general, genetic predisposition to diverticular disease involves conditions that alter colonic wall integrity, conditions that cause visceral neurological dysfunction, and those that result in change of stool consistency.  These three different mechanisms, which all cause the same phenotype, support the concept that the pathophysiology of diverticular formation is multifactorial. 
It worth noting that majority of our patients was either overweight or obese. Whether obesity is a result of the dietary features in this at-risk population or a risk factor in itself is difficult to know. Nonetheless, previous reports had shown that there is significant association between obesity and complications of diverticular disease, particularly in younger patients. ,, We found that there is significant association between obesity and the presentation of diverticular disease. The obese patients presented with bleeding per rectum whereas those with normal BMI presented with pain. A greater incidence of diverticulitis and bleeding was seen in patients with greater waist-to-hip ratios as well-an association that persisted with adjustment for BMI.  A large Swedish study also found a greater incidence of hospitalization for diverticular disease in overweight and obese patients.  It has been suggested that because obesity has been linked to inflammation and differences in the intestinal flora, these mechanisms should be considered for the increased risk of diverticulitis. 
The most common presentation in African patient with diverticular disease is rectal bleeding, as also shown in this study. ,, In developed countries, however, the most common presentation is sepsis. , Differences in diet had been used to explain the disparity in presentation in African and Western countries. High fiber diet may tend to prevent sepsis by ensuring regular fecal flow thereby reducing blockage at the neck of the diverticular disease and prevent stasis, bacterial proliferation, and sepsis.  It may also be possible that the frequent use of over the counter antibiotic for suspected infective gastrointestinal conditions; reduce the frequent occurrence of diverticulitis.
The most widely available and accurate examination of patients with diverticular disease in developed countries is the abdominal CT. ,, This investigation modality is more relevant in patient with associated sepsis. Advantages of CT scanning include the ability to make an accurate diagnosis and stage the severity of disease, and the therapeutic ability to drain an abscess with CT guidance. Disadvantages of CT scan in developing countries include radiation exposure and the cost of the examinations. Since most of our patients present with bleeding per rectum; hence colonoscopy can be regarded as the investigation modality of choice in African patients having diverticular disease. This procedure should, however, be performed by skilled individual to prevent complication. Performing colonoscopy in these patients also serve as an opportunity to screen them for colorectal cancer especially in our environment where national wide screening for the disease is not available. In our series, some of the patients had coexisting colonic polyps and hemorrhoids. We found no case of coexisting colorectal cancer in our patients. Though inconclusively, it has been suggested that the incidence of colorectal cancer increases in patients with diverticular disease.  This is because both disease conditions have common risk factor. Similarly, the elevated risk of colorectal cancer in diverticular disease can be associated to chronic inflammation, which often occurs in it. 
Majority of our patients had the disease involving the entire colon, whereas only few had the disease restricted to the right. Although most African studies showed the preponderance of the disease on the right colon as common among the Asian descent, ,, some showed the occurrence of the disease on the left colon with the site of predilection being the descending colon.  Hence, diverticular disease affects predominantly the right colon in Japanese, Thais, Chinese in Hawaii, and Chinese, Malays, and Indians in Singapore, whereas the most common site of diverticula in Western populations is the sigmoid colon, which is involved in 95% of patients.  The reason for this variation in anatomic discrepancy is unknown, although it may not be unconnected to the diet.
Most of the patients responded to conservative management, which comprises of increase intake of high fiber diet and antibiotics. Recently, poorly absorbed antibiotics such as Rifaximin and Mesalazine are now been used to treat diverticular disease in most industrialized countries.  These drugs are not available in Nigeria. The rational for the use of antibiotics is that bacterial overgrowths from intraluminal stasis in diverticula give rise to chronic low-grade mucosal inflammation. This sensitizes intrinsic primary efferent neurons in the submucosal and myenteric plexus, inducing visceral hypersensitivity and changes in colonic motor function. , The alterations in neurochemical transmitters also explain the changes in colonic motility and development of abdominal symptoms. 
Until recently, most patients were offered elective resection after two documented attacks of uncomplicated diverticulitis. This recommendation is based on the early works of Parks.  Recently, this recommendation have been challenged. Salem and Flum suggested that waiting until the fourth attack of uncomplicated diverticular disease would be associated with fewer deaths and fewer intestinal stomas.  Another decision analysis concluded that elective resection after the third attack would be more cost-effective.  Furthermore, a number of large reviews have suggested that the common practice of operating after the second episode of diverticulitis should be reconsidered. , However, the American Society of Colon and Rectal Surgeons currently states that the "number of attacks of uncomplicated diverticulitis is not necessarily an overriding factor in defining the appropriateness of surgery. Patients selection for surgery should be on case by case basis".  In our setting, adequate information should be given to patients following recurrence and patients should be given opportunity to choose. Fear of surgery by an average Nigerian will limit the use of surgery.
One other finding of this study is the important of concurrent drug use in the occurrence of bleeding and re-bleeding. Nonsteroidal antiinflammatory drug notably aspirin has been shown to increase complication resulting from diverticular disease.  Although the reason for the association in not known yet. The plausible biological explanation for this may be related to the reduction in prostaglandin synthesis and alterations in large intestine mucus secretion and large intestine permeability. , All this factors decrease colonic wall integrity and hence increase in complication associated with diverticular disease.
| Conclusion|| |
Colonic diverticular disease is not uncommon among Nigerians. Lower gastrointestinal bleeding is a common mode of presentation. It tends to involve all part of the colon. Majority respond to conservative management. High index of suspicion for diverticular disease of the colon and its complications should increase in the country
| References|| |
|1.||Tarleton S, DiBaise JK. Low-residue diet in diverticular disease: Putting an end to a myth. Nutr Clin Pract 2011;26:137-42. |
|2.||Sandler RS, Everhart JE, Donowitz M, Adams E, Cronin K, Goodman C, et al. The burden of selected digestive diseases in the United States. Gastroenterology 2002;122:1500-11. |
|3.||Jacobs DO. Clinical practice. Diverticulitis. N Engl J Med 2007;357:2057-66. |
|4.||Painter NS, Burkitt DP. Diverticular disease of the colon: A deficiency disease of western civilization. Br Med J 1971;2:450-4. |
|5.||Floch MH, White JA. Management of diverticular disease is changing. World J Gastroenterol 2006;12:3225-8. |
|6.||Parra-Blanco A. Colonic diverticular disease: Pathophysiology and clinical picture. Digestion 2006;73:(Suppl 1):47-57. |
|7.||Stollman N, Raskin JB. Diverticular disease of the colon. Lancet 2004;363:631-9. |
|8.||Madiba TE, Mokoena T. Pattern of diverticular disease among Africans. East Afr Med J 1994;71:644-6. |
|9.||Mokoena T, Madiba TE. Haemorrhagia-The main presenting feature of diverticular disease in blacks. S Afr Med J 1994;:83-5. |
|10.||Manwaring M, Champagne B. Diverticular disease: Genetic, geographic, and environmental aspects. Semin Colon Rectal Surg 2011;22:148-53. |
|11.||Martel J, Raskin JB; NDSG. History, incidence, and epidemiology of diverticulosis. J Clin Gastroenterol 2008;42:1125-7. |
|12.||Ogunbiyi OA. Diverticular disease of the colon in Ibadan, Nigeria. Afr J Med Med Sci 1989;18:241-4. |
|13.||Dabestani A, Aliabadi P, Shah-Rookh FD, Borhanmanesh FA. Prevalence of colonic diverticular disease in southern Iran. Dis Colon Rectum 1981;24:385-7. |
|14.||Rajendra S, Ho JJ. Colonic diverticular disease in a multiracial Asian patient population has an ethnic predilection. Eur J Gastroenterol Hepatol 2005;17:871-5. |
|15.||Kiguli-Malwadde E, Kasozi H. Diverticular disease of the colon in Kampala, Uganda. Afr Health Sci 2002;2:29-32. |
|16.||Baako BN. Diverticular disease of the colon in Accra. Ghana. Br J Surg 2001;88:1595. |
|17.||Salzman H, Lillie D. Diverticular disease: Diagnosis and treatment. Am Fam Physician 2005;72:1229-34. |
|18.||Ihekwaba FN. Diverticular disease of the colon in black Africa. J R Coll Surg Edinb 1992;37:107-9. |
|19.||Lee YS. Diverticular disease of the large bowel in Singapore. An autopsy survey. Dis Colon Rectum 1986;29:330-5. |
|20.||Eide TJ, Stalsberg H. Diverticular disease of the large intestine in Northern Norway. Gut 1979;20:609-15. |
|21.||Jun S, Stollman N. Epidemiology of diverticular disease. Best Pract Res Clin Gastroenterol 2002;16:529-42. |
|22.||Warner E, Crighton EJ, Moineddin R, Mamdani M, Upshur R. Fourteen-year study of hospital admissions for diverticular disease in Ontario. Can J Gastroenterol 2007;21:97-9. |
|23.||Omojola MF, Mangete E. Diverticula of the colon in three Nigerian siblings. Trop Geogr Med 1988;40:54-7. |
|24.||Schlotthauer HL. Familial diverticulosis of the colon: Report of seven cases in one family of nine persons. Ann Surg 1946;124:497-502. |
|25.||Dobbins C, Defontgalland D, Duthie G, Wattchow DA. The relationship of obesity to the complications of diverticular disease. Colorectal Dis 2006;8:37-40. |
|26.||Zaidi E, Daly B. CT and clinical features of acute diverticulitis in an urban U.S. population: Rising frequency in young, obese adults. AJR Am J Roentgenol 2006;187:689-94. |
|27.||Strate LL, Liu YL, Aldoori WH, Syngal S, Giovannucci EL. Obesity increases the risks of diverticulitis and diverticular bleeding. Gastroenterology 2009;136:115-22.e1. |
|28.||Rosemar A, Angerås U, Rosengren A. Body mass index and diverticular disease: A 28-year follow-up study in men. Dis Colon Rectum 2008;51:450-5. |
|29.||Parks TG. Natural history of diverticular disease of the colon. Clin Gastroenterol 1975;4:53-69. |
|30.||Lawrimore T, Rhea JT. Computed tomography evaluation of diverticulitis. J Intensive Care Med 2004;19:194-204. |
|31.||Kaiser AM, Jiang JK, Lake JP, Ault G, Artinyan A, Gonzalez-Ruiz C, et al. The management of complicated diverticulitis and the role of computed tomography. Am J Gastroenterol 2005;100:910-7. |
|32.||Soran A, Harlak S, Wilson JW, Nesbitt L, Lembersky BC, Wie HS, et al. Diverticular disease in patients with colon cancer: Subgroup analysis of national surgical adjuvant breast and bowel project protocol C-06. Clin Colorectal Cancer 2006;6:140-5. |
|33.||Segal I, Leibowitz B. The distributional pattern of diverticular disease. Dis Colon Rectum 1989;32:227-9. |
|34.||Sopena F, Lanas A. Management of colonic diverticular disease with poorly absorbed antibiotics and other therapies. Therap Adv Gastroenterol 2011;4:365-74. |
|35.||Gonzales ER, Alavi K. Evaluation and treatment of uncomplicated diverticular disease. Semin Colon Rectal Surg 2011;22:162-8. |
|36.||Colecchia A, Sandri L, Capodicasa S, Vestito A, Mazzella G, Staniscia T, et al. Diverticular disease of the colon: New perspectives in symptom development and treatment. World J Gastroenterol 2003;9:1385-9. |
|37.||Salem L, Flum DR. Primary anastomosis or Hartmann's procedure for patients with diverticular peritonitis? A systematic review. Dis Colon Rectum 2004;47:1953-64. |
|38.||Richards RJ, Hammitt JK. Timing of prophylactic surgery in prevention of diverticulitis recurrence: A cost-effectiveness analysis. Dig Dis Sci 2002;47:1903-8. |
|39.||Chapman J, Davies M, Wolff B, Dozois E, Tessier D, Harrington J, et al. Complicated diverticulitis: Is it time to rethink the rules? Ann Surg 2005;242:576-81. |
|40.||Janes S, Meagher A, Frizelle FA. Elective surgery after acute diverticulitis. Br J Surg 2005;92:133-42. |
|41.||Rafferty J, Shellito P, Hyman NH, Buie WD; The Standards Task Force, the American Society of Colon and Rectum Surgeons. Practice parameters for sigmoid diverticulitis. Dis Colon Rectum 2006;49:939-44. |
|42.||Humes DJ, Fleming KM, Spiller RC, West J. Concurrent drug use and the risk of perforated colonic diverticular disease: A population-based case control study. Gut 2011;60:219-24. |
|43.||Laine L, Smith R, Min K, Chen C, Dubois RW. Systematic review: The lower gastrointestinal adverse effects of non-steroidal anti-inflammatory drugs. Aliment Pharmacol Ther 2006;24:751-67. |
[Figure 1], [Figure 2], [Figure 3]