Diverticulosis and Diverticular Disease
Signs and Symptoms
About 80‒85% of individuals with diverticulosis will never experience any symptoms; about 10‒15% will develop diverticular disease; and roughly 5% will have at least one episode of acute diverticulitis (Bugiantella 2015). For those who develop diverticular disease, symptoms can have a rapid, or acute, onset, or can be ongoing and chronic, and can vary in intensity from mild to severe (Sopena 2011; Boynton 2013).
Chronic Diverticular Disease
There are several different specific symptom patterns of chronic diverticular disease:
Symptomatic uncomplicated diverticular disease (SUDD). This condition is characterized by recurring or persistent lower left abdominal pain, bloating, and constipation or diarrhea, in the absence of diverticulitis. SUDD can resemble irritable bowel syndrome. Fever, elevated white blood cell count, and other signs of an infectious or inflammatory condition are not characteristic of SUDD (Tursi 2010).
Segmental colitis associated with diverticulitis (SCAD). SCAD is thought to occur in about 0.3‒1.3% of people with diverticulosis, and appears to be similar to inflammatory bowel disease. The symptoms most commonly associated with SCAD are rectal bleeding, diarrhea, and abdominal pain; fever and elevated white blood cell count do not usually occur with this condition (Mann 2012).
Chronic diverticulitis. Chronic diverticulitis is characterized by mild and persistent diverticular inflammation that may cause abdominal pain but usually does not cause fever (Sheiman 2008).
Acute Diverticular Disease
The characteristic symptom of acute diverticulitis is pain in the lower left abdomen that tends to worsen with movement; pain may also be right-sided or originate in other parts of the abdomen. Fever, usually below 102°F, is another common symptom. Other possible symptoms include abdominal bloating, lack of appetite, nausea (generally without vomiting), constipation or diarrhea, and painful urination. In severe acute diverticulitis, the abdomen may become stiff and rigid (Wilkins 2013; Medina-Fernandez 2015).
An episode of acute diverticulitis may become a medical emergency necessitating surgical intervention if complications arise. Potential complications include bleeding, abscess, fistula, perforation, or obstruction (Schaffzin 2004; Köckerling 2015).
Figure 1: The Spectrum of Conditions Associated with Diverticula (Collins 2015; Strate 2012)
Distinguishing Symptomatic Uncomplicated Diverticular Disease from Irritable Bowel Syndrome
Symptomatic uncomplicated diverticular disease (SUDD) may be confused with irritable bowel syndrome (IBS) due to the overlap in their hallmark symptoms: abdominal discomfort or pain and disturbance in bowel habits (Spiller 2012). It can also be difficult to distinguish these conditions because they appear to co-occur in many people (Jung 2010; Yamada 2014).
What’s more, researchers speculate that a bout of acute diverticulitis may trigger colonic sensory and motor nerve damage, changes in bacterial ecology, and mucosal inflammation, resulting in a set of chronic abdominal and digestive symptoms sometimes referred to as “post-diverticulitis IBS.” One study found that people with a history of diverticulitis were 4.6 times more likely to receive a diagnosis of IBS during a nine-year period than people without a history of diverticulitis (Strate, Modi 2012).
A correct diagnosis is critical in these cases, since surgery may be a reasonable choice for someone with recurrent acute diverticulitis but is likely to yield poor results in IBS (Spiller 2014).
It appears that the pattern of abdominal pain may be helpful in distinguishing SUDD from IBS. In one study, 72 people with colonoscopy-confirmed diverticulosis and suffering from abdominal pain were given a preliminary diagnosis of either SUDD or IBS-like symptoms, based on the location and duration of their pain; those with lower left-sided abdominal pain lasting more than 24 hours met the diagnostic criteria for SUDD, and those with pain in other parts of their abdomen were considered to have IBS-like symptoms. Researchers then found that no one in the IBS-like symptom group, and 64% of those in the SUDD group, had elevated fecal calprotectin, a marker of intestinal inflammation, thereby showing that moderate-to-severe lower left-sided pain lasting more than 24 hours is correlated with diverticular disease (Tursi 2015).