What Is Terminal Ileitis? (2024)

Terminal ileitis is the inflammation of the terminal end of the ileum, which is the last section of the small intestine before it leads into the large intestine. This inflammation affects the health of the gastrointestinal (GI) system, causing gastrointenstinal symptoms such as abdominal pain and cramping or diarrhea.

Terminal ileitis is often associated with Crohn’s disease, a form of inflammatory bowel disease, but Crohn's is not always the cause. Because terminal ileitis can be caused by multiple conditions, understanding the underlying cause is crucial to getting the right treatment.

This article will discuss the symptoms, diagnostic tests, and treatment options for terminal ileitis.

Terminal Ileitis Symptoms

Symptoms of terminal ileitis vary, but may include:

• Lower abdominal pain and cramps
• Diarrhea
• Bloody diarrhea

Guidance for how to manage terminal ileitis without symptoms varies. Research suggests that if there are no digestive symptoms or history of Crohn’s disease with a case of terminal ileitis, the risk of developing Crohn’s is rare, and further testing or treatment may not be recommended.

Terminal Ileitis and Crohn's Disease

Ileitis is commonly associated with Crohn’s disease, a chronic digestive disease caused by inflammation of the colon, but many other conditions affect the ileum.

Researchers have looked closely at the connection between terminal ileitis and Crohn’s disease and found limited evidence that terminal ileitis leads to Crohn’s. One group of researchers examined the progression between the two conditions and found that terminal ileitis without a history of inflammatory bowel disease rarely progresses to Crohn’s disease, with only 5% of their cases doing so.

However, there may be some indicators specific to terminal ileitis-related Crohn’s disease. For instance, research suggests that narrowing of the bowel wall, as seen on abdominal imaging, may be indicative of terminal ileitis that will progress to Crohn’s disease.

Causes

Some other conditions that can cause inflammation of the terminal ileum include ulcerative colitis, intestinal infections, lymphoma, lymphoid hyperplasia, and nonsteroidal anti-inflammatory drug (NSAID) use.

When looking at ileitis on its own, there is evidence that it shares some of the same genetic (NOD2) mutations as Crohn’s disease. Besides a genetic component, inflammation could result from physical damage to the lining of the ileum.

Some cases of terminal ileitis may be due to lesions on the ileum. For example, terminal ileitis may show up as small ulcers on the ileum, though it is rare and will often just show up as non-specific inflammation.

As the causes of terminal ileitis vary quite a bit, medical help is critical to get to the root cause of terminal ileitis so that the right diagnosis is reached.

Diagnosis

Terminal ileitis on its own (also known as isolated acute terminal ileitis) is difficult to diagnose because it doesn’t have the same chronic characteristics as inflammatory bowel disease.

Furthermore, other pathological conditions such as Crohn’s disease can look like terminal ileitis. Thus, it may be misdiagnosed as Crohn’s.

Tests used to diagnose terminal ileitis include:

Colonoscopy

A colonoscopy with an ileoscopy is a procedure in which a thin scope with a camera on the end is threaded through the colon to look for abnormalities. During the ileoscopy, the scope is guided into the small intestine to look specifically at the ileum.

Biopsy

In some cases, your doctor may take a biopsy (a small tissue sample) of the terminal ileum during the colonoscopy and ileoscopy to be sent back to the lab and examined under a microscope. This can help your doctor make a definitive diagnosis.

Treatment

Treatment for terminal ileitis depends on its cause. For example, if terminal ileitis is the result of Crohn’s disease, treatment for Crohn’s disease will follow.

Some cases of terminal ileitis may not be harmful, as is sometimes the case with asymptomatic terminal ileitis, and therefore no further workup or treatment may be needed.

These different pathways highlight the importance of getting the right diagnosis. Knowing the root problem is key to knowing how to proceed with treatment.

Summary

Terminal ileitis is an inflammation of the terminal ileum, the very end of the small intestine. The condition can cause symptoms such as diarrhea and abdominal cramping.

While terminal ileitis is often associated with Crohn’s disease, it can be caused by various other conditions of the gastrointestinal system. An accurate diagnosis from a medical professional is crucial to moving forward with the best treatment plan for your situation.