Understanding diverticular disease

Diverticulosis, diverticula, diverticulum, and diverticulitis - they may sound similar, but each term describes a specific aspect of diverticular disease. Before diving into diverticular disease, let’s clarify these key terms:

• Diverticulum: a small, bulging pouch that forms in a weak spot in the lining of the large intestine.

• Diverticula: the plural form of a diverticulum, indicating multiple bulging pouches in the large intestine's lining.

• Diverticulosis: a condition where multiple diverticula are present in the large intestine.

• Diverticulitis: this occurs when one or more diverticula become inflamed or infected.

What is diverticular disease?

Diverticular disease can be broadly categorised into two main conditions: diverticulosis and diverticulitis. Both involve the presence of diverticula in the colon, but the key difference lies in inflammation. In diverticulitis, the diverticula become inflamed or infected, leading to symptoms. On the other hand, diverticulosis is typically asymptomatic. However, there is a third condition, referred to as symptomatic uncomplicated diverticular disease (SUDD), where diverticula are present without inflammation, but the patient still experiences symptoms.

The prevalence of diverticulosis is increasing in developed countries, largely due to the typical 'Western diet', which is high in red meat and low in fibre. Additionally, lifestyle factors such as obesity, smoking, and physical inactivity contribute to this rise. Age is also a significant factor, with 85% of diverticulosis cases occurring in individuals over the age of 50.

Pathophysiology

The formation of diverticula in the colon is primarily due to three factors: structural abnormalities in the colonic wall, disordered intestinal motility, and a deficiency of dietary fibre.

The large intestine has two layers of muscle that work together to move its contents: an inner circular layer and an outer longitudinal layer. The outer layer consists of three bands called the taeniae coli, which run longitudinally along the colon. The gaps between these muscle bands are areas of weakness, making them vulnerable to the development of diverticula. Age-related weakening of the connective tissue further increases the risk of developing diverticula in these vulnerable areas.

In some patients, abnormal gut motility can lead to areas of high pressure in the bowel, causing the mucosa to bulge outward, forming diverticula. Similarly, a lack of fibre in the diet can increase bowel pressure and lead to irregular movement, which also promotes outpouching.

As we've discussed, some patients with diverticula may remain asymptomatic, while others experience varying levels of discomfort. The transition from diverticulosis to diverticulitis occurs when undigested food or a fecalith becomes trapped in these pouches, causing a blockage. This leads to bacterial growth and multiplication, resulting in infection and inflammation of the pouch.

 Symptoms

Diverticular disease comes with a range of symptoms, some of which are quite common and could be easily mistaken for other conditions. General symptoms like nausea, vomiting, diarrhoea, and fever often overlap with other digestive problems, making diagnosis tricky. However, certain symptoms can hint more strongly at diverticular disease. For instance, experiencing pain in the lower left side of the abdomen (known as the left iliac fossa) or noticing rectal bleeding are more specific indicators that may point towards this condition. Recognising these symptoms can help in getting a more accurate diagnosis and appropriate treatment.

Management

Managing diverticular disease depends on the individual patient and the severity of their symptoms. For some, simple, conservative treatments are enough—this might include staying hydrated, eating a high-fibre diet, and giving the bowel a short rest by temporarily avoiding food. However, if a patient is experiencing significant pain or signs of infection, medical treatment is necessary. This may involve pain relief based on the WHO pain ladder or antibiotics to tackle the infection.

In more serious cases, where other treatments haven’t worked or the patient is in a life-threatening situation, surgery might be required. A common procedure for these severe cases is the Hartmann’s procedure. This surgery removes the damaged section of the large intestine, usually due to infection or blockage. The healthy end of the intestine is brought out through an opening in the abdomen, creating a temporary colostomy that allows waste to leave the body through a bag. This setup gives the intestine time to heal, and in some cases, a follow-up surgery can reconnect it for normal function.

Complications

There are both short-term and long-term complications associated with diverticulitis, particularly in more severe cases that require more aggressive treatment such as surgery (see Figure 4).

Future directions

Recent changes in the management of diverticulitis have shifted how clinicians approach treatment. One significant update involves the use of antibiotics. Traditionally, diverticulitis was treated with routine antibiotic prescriptions. However, newer guidelines suggest that antibiotics may not be necessary for uncomplicated cases, helping to reduce both antibiotic resistance and the potential medication side effects for patients.

Another emerging trend is treating uncomplicated diverticulitis on an outpatient basis. This allows patients to be managed at home with pain relief and dietary adjustments, which in turn frees up hospital resources for those with more severe conditions. Additionally, the management of complicated diverticulitis has evolved. For instance, abscesses may now be treated with percutaneous drainage rather than resorting to emergency surgery.

Conclusion

In summary, diverticular disease can vary widely in its symptoms and required treatments, ranging from dietary changes to surgical interventions for severe cases. Identifying specific signs and understanding the treatment options can empower patients and help them make informed choices. Advances in treatment approaches are also helping to improve outcomes and quality of life for those affected.

Written by Abbasali Gulamhussein

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REFERENCES

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Ubhi, L. (2023). Prescribing Analgesia and the WHO Analgesic Ladder | Geeky Medics. [online] geekymedics.com. Available at: https://geekymedics.com/prescribing-analgesia-and-the-who-analgesic-ladder/.