Can Constipation Cause Appendicitis? Gastroenterologist Explains.

The exact cause of appendicitis is still unknown. Obstructing the appendix by a hard stool mass (fecalith) is known to cause appendicitis.

However, fecalith is found in a minority of the cases. We don’t know the exact trigger of appendicitis in most cases.

A stool build-up inside the appendix often causes fecalith (hard stool mass). Researchers believe that a low-fiber diet and constipation can lead to appendix fecality.

Constipation is a risk factor for appendicitis.

Constipation is proposed as a cause of appendicitis in various studies. The overall evidence that constipation cause appendicitis is still weak (reference).

Dr. Raahave did the most prominent study investigating the link between constipation and acute appendicitis in 2015 (reference).

Dr. Raahave found that patients with chronic constipation were more likely to have appendectomy than healthy controls.

Moreover, People who have had appendectomy before have more profound constipation. Prolonged retention of feces appears to play a role in the development of appendicitis.

Another study found that chronic constipation is higher in children with acute appendicitis (reference). The same study proposed that appendicitis can result from a low-fiber diet and constipation.

The fiber in the diet is essential for regular bowel movements. People who fail to obtain sufficient fiber in their diet are at higher risk of constipation.

Conclusion:

Constipation is a possible factor causing appendicitis. People with chronic constipation are at a slightly higher risk of developing appendicitis.

Possible mechanisms of constipation-induced appendicitis.

The most crucial trigger of appendicitis is the obstruction of its lumen. Lumen obstruction can be due to the following:

• Fecalith (hard stool mass, can be due to constipation).
• Enlarged lymphatics in the appendix wall (lymphoid hyperplasia).
• Appendix stone.
• Tumors of the appendix or the caecum.

However, The above factors are rarely detected with appendicitis. We currently don’t fully understand the mechanism of appendicitis.

Fecalith is a result of constipation.

People with chronic constipation often have problems with their colon motility. Chronic constipation can lead to stool build-up (fecal retention) inside the colon and appendix.

The stool trapped inside the appendix loses water and hardens over time, forming a fecalith.

This study compared 56 patients with chronic constipation to 44 healthy controls. Patients with constipation were found to be at higher risk of fecalith formation and appendicitis (reference).

Moreover, chronic constipation is a possible risk for complicated appendicitis. The presence of fecalith increases the risk of appendix gangrene (death of its tissues) and perforation.

Low fiber intake may be because of constipation and appendicitis.

Low fiber intake is a risk factor for constipation and possibly acute appendicitis.

One study found that US children with good fiber intake have a 30% lower risk of appendicitis than children with low fiber intake (reference).

Constipation pain can lead to a false diagnosis of appendicitis.

Patients with chronic constipation are predominantly females. In addition, females with chronic constipation tend to have more than multiple functional bowel diseases.

One interesting study found that patients with functional bowel diseases can have attacks of severe abdominal pain similar to appendicitis.

Doctors can misdiagnose severe abdominal pain associated with IBS-C and other functional gut diseases as acute appendicitis. This may lead to unnecessary abdominal surgeries such as appendectomy.

This study found the appendix normal in 36% of appendectomy operations done for young females with severe abdominal pain (reference). Constipation-related abdominal pain leads to a false diagnosis of appendicitis in 13% of the cases.

The abdominal pain was attributed to functional disorders such as irritable bowel syndrome and chronic constipation.

Also, other conditions, such as nonspecific abdominal pain (NSAP), gastroenteritis, and gynecological diseases, can lead to a false-positive diagnosis of appendicitis.

What we know about the causes of appendicitis:

As we explained, we don’t know the exact cause of appendicitis in most cases. The evidence is still weak regarding the role of constipation in appendicitis.

To give an idea about what we know about the causes, we gathered the most important facts from research(reference):

• Appendicitis occurs primarily due to appendix obstruction, predisposing to pus and mucus build-up infection leading to appendicitis.
• Also, several infections can trigger appendicitis, but no specific patterns of infections are specific to appendicitis. 
• Neither obstruction nor infection can explain all cases of appendicitis.
• If one of your family members had appendicitis before, you are three times more likely to develop appendicitis (possibly due to genetic factors).
• Environmental factors can also cause appendicitis. For example, appendicitis is more common in summer than in winter.
• The white races are at higher risk of appendicitis than non-whites.