Diverticulitis

Original Editors - Cate Hurst and Katie Countryman from Bellarmine University's Pathophysiology of Complex Patient Problems project. Top Contributors - Katie Countryman, Cate Hurst, Khloud Shreif, Alexandra Stead, Elaine Lonnemann, Lucinda hampton, Kim Jackson, WikiSysop, 127.0.0.1, George Prudden and Karen Wilson  

Introduction

Showing multiple pouches (diverticula) colon

Colonic diverticulitis is a possible adverse result of colonic diverticulosis that develops adjacent to blood vessels that penetrate these layers. Diverticulosis is mainly asymptomatic whilst acute diverticulitis is a potentially life-threatening illness. Colonic diverticulosis is characterised by the protrusion of both mucosa and submucosa layers of the colon and the sigmoid colon is the most affected segment of the colon. However, in recent studies its prevalence is more common in younger ages for years it was believed to be associated with old age above 50 years old as it was in the united Kingdom.

Epidemiology

Diverticulitis is a complication of diverticulosis. Research indicates that approximately one in four patients with diverticulosis will develop acute diverticulitis during their lifetime. Despite sophisticated colonoscopy and CT scans, diverticulitis still remains common in the US, where more than half of Americans aged above 60 have diverticulosis. The prevalence of diverticulitis usually rises along with the age of the patient; however, during recent years, there has been an increase in the occurrence of diverticulitis even among young people, which reached a 132% growth rate in diverticulitis cases among the 40-49-year-old population between 1980 and 2007. The highest rates of hospitalisation for diverticulitis are found in Caucasians (62 out of 100,000), followed by similar rates among African Americans and Hispanics (approximately 30 out of 100,000), and Asians have the lowest rates (10 per 100,000). Notably, compared to natives of Western countries immigrants from non-Western countries initially exhibit a lower risk of being hospitalised for diverticular disease, however, this risk increases with the length of their stay in the new country.

In more recent years, there has been great comparisons between right and left sided Diverticulitis. Although both conditions stem from the same fundamental inflammatory process affecting diverticula, right-sided and left-sided colonic diverticulitis can be viewed as distinct clinical entities, with right-sided diverticulitis is its clinical similarity to acute appendicitis. They differ in their underlying pathology, how patients present with symptoms, and how the disease progresses. Whilst left colonic diverticulitis is traditionally found in Western countries, a recent study has found right colonic diverticulitis to be more common in Asian populations, though a more benign form of the disease, it seems to impact a younger population.

Pathophysiology

Colon pouches

Diverticulitis develops through a complex, multi-stage pathological process that begins with the formation of diverticula and progresses through inflammation, infection, and potential complications.

The initial stage involves the formation of diverticula, which are small pouches that protrude through weak points in the colonic wall. These weak points typically occur where blood vessels penetrate the muscular layers of the colon. Diverticula develop when increased intraluminal pressure, often resulting from chronic straining during defecation or low dietary fibre intake, causes the mucosa and submucosa to herniate through the muscular wall. The sigmoid colon is most commonly affected due to its smaller diameter and higher intraluminal pressures.

Once diverticula are present, inflammation and infection may occur when a diverticulum becomes obstructed, typically by inspissated faecal material or undigested food particles. This obstruction creates a closed environment that promotes bacterial overgrowth and subsequent inflammation of the diverticular wall. The normal colonic microbiome becomes pathogenic in this stagnant environment, leading to local infection and inflammatory changes.

As inflammation progresses, alterations in the local microbiome further contribute to tissue damage. The inflammatory process can compromise the integrity of the diverticular wall, potentially leading to microperforation or, in more severe cases, macroperforation. Microperforation may result in a contained, localised infection with pericolic fat stranding visible on imaging. Macroperforation can lead to abscess formation when the perforation is walled off by adjacent structures, or to generalised peritonitis if bowel contents spill freely into the peritoneal cavity.

The body's immune response to infection and inflammation plays a crucial role in disease progression. Whilst the immune response may facilitate healing and resolution of the acute inflammatory episode, an excessive or prolonged inflammatory reaction can lead to complications. Significant inflammation may cause fibrous tissue formation and scarring of the bowel wall, potentially resulting in stricture formation and bowel obstruction. Recurrent episodes of inflammation can lead to chronic structural changes in the affected colonic segment.

In severe cases, the inflammatory process may extend beyond the bowel wall to involve adjacent organs, creating abnormal communications known as fistulae. Common fistulous connections include colovesical (to the bladder), colovaginal (to the vagina), and coloenteric (to other bowel segments) fistulae. Additionally, erosion into blood vessels can result in significant gastrointestinal haemorrhage, though this complication is relatively uncommon, occurring in approximately 1-2% of patients with severe disease.

Aetiology

Colonic diverticular development may involve bowel wall abnormality, increased intraluminal pressure, and lack of dietary fibre. Diverticulitis is the result of obstruction of the neck of the diverticulum (outpouch), with consequential inflammation, perforation, and infection. A walled region of soft tissue may later progress to abscess formation and generalised peritonitis.

Risk Factors:

• Increased age.
• Constipation
• Sedentary lifestyle
• Obesity (especially central obesity)
• Smoking
• NSAIDS
• Dietary patterns that include (Red meat, processed grains, and fat)
• Genetic factors.

Characteristics/Clinical Presentation

The presentation and signs and symptoms can vary for each individual patient. Although many of the patients have the same side effects, they are usually experienced at different intensities and at various times. Some of the most common signs and symptoms that are present with the diverticulitis diagnosis include the following:

• Sudden abdominal pain, usually in the left lower quadrant abdomen (up to 70% of cases), and is often associated with an increase in inflammatory markers and temperature.
• Palpable mass
• Irregular bowel movements and changes in bowel habits.
• Bowel sounds absent or decreased
• Flatulence
• Fever
• Nausea/ Vomiting
• Bloody stools
• Increased frequency of urination

Possible complications include perforation of bowels, and abscess formation that seen in around 17% of patients, fistula formation, gastrointestinal haemorrhage, obstruction, bleeding, and perforative peritonitis in 1-2% of patients.

Diagnosis

Diverticulitis is typically diagnosed during an acute attack due to complaints of severe abdominal pain. Diverticulitis diagnosis is typically confirmed with the presence of constitutional symptoms, bloody stools, elevated white blood cell count, and with the use of imaging studies. Due to the prevalence of abdominal pain in several conditions, the physician may order a number of tests to rule out other causes of abdominal pain and associated symptoms.

Ultrasound: good to detect simple cases of diverticular disease.

CT scan: helps to provide detailed and specific results. This will be helpful in monitoring treatment progress and planning future interventions. Divergent disease classification depends on CT results.

Endoscopic evaluation: it can be used for tissue diagnostics and is useful for direct visualisation, their use in acute attacks of diverticular disease is controversial because of the potential risks and is often avoided in these cases. In the post-attack setting, there is some debate as to whether a colonoscopy should be performed routinely. However, some experts recommend the use of flexible sigmoidsoscopy because of its less invasive nature and the fact that the sagittal region of the colon is the area most affected by diverticular disease..

Classification of Diverticulitis Depending on CT scan

Class	CT findings
Mild disease	Bowel wall thickening, fat stranding
Moderate disease	Bowel wall thickness >3 mm, phlegmon/small abscess
Severe disease	Bowel wall thickening >5 mm, perforation with subdiaphragmatic free air, abscess >5 mm

Treatment

Treatment depends on a range of factors, in particular comorbidities and stage of the disease. Diverticulitis can be treated with rest, changes in diet, or antibiotics, and in severe cases may require surgery.

• Localised disease: conservative management with intravenous antibiotics and rehydration usually is enough, the antibiotics should be for both aerobic and anaerobic bacteria especially for mild cases to avoid and reduce the risk of developing complications as advised by American Gastroenterology Association.
• Surgery maybe required if a patient has a complication (abscess, fistula formation, bowel obstruction), has had multiple episodes of uncomplicated diverticulitis, or is immune-compromised. Surgery may be recommended or it may require emergency surgery. however, instead of deciding on elective segmental resection just by counting the number of episodes, it's better to make a personalised choice. This should involve considering how severe the disease is, what the patient prefers and values, and the risks and benefits of the procedure.
• Hartmann’s procedure is the most common surgery used to treat complex diverticular disease. It is a type of surgery only used in very serious cases. Hartmann removes the diseased part of colon (usually called the “sigmoid” section) and creates a temporary colostomy, in which the end of your remaining colon is pulled out to belly button. .

Prevention of diverticulitis is from a variety of lifestyle changes. Lifestyle modifications that may reduce diverticulitis risk include maintaining a high-fibre diet, limiting red meat consumption, preventing constipation through adequate fluid intake, and smoking cessation. Regular physical activity during remission periods is also beneficial.

Physical Therapy Management

McBurney's Point

As a physical therapist, the optimal goal is to help a patient return to moving in a functional way. Being active helps decrease the chances of developing diverticulitis because movement helps promote proper bowel movement. Therapists can help patients with proper exercise, strengthening, and positioning to help them get the best and safest movement possible. Patients with diverticulitis must be cautious about doing activities that increase the pressure on their abdomen so further herniation does not happen. In addition, vigorous activity like running is associated with decrease risk of diverticular disease.

Exercise can be seen as a protective mechanism because it promotes movement to the body, but also the different systems that could be affected by a sedentary lifestyle. Depending on the symptoms that the patients present with, it is up to the therapist to do appropriate screening or testing to identify what is involved and what is causing the issues.

The therapist can advise and encourage the patient to maintain a lower bod mass index, be physically active, and consume high-quality diet rich in in fruits, vegetables, and whole grains.

A common area of pain is the left lower quadrant, including referred pain to the lower back or thigh from an abscess. For example, the obturator test, manual muscle testing and palpation of the iliopsoas, or McBurney’s point palpation can be done to look at positive or negative testing of referred pain to the thigh.