An Overview of Small Bowel Diverticula

Small bowel diverticula (also called small intestine diverticular disease) is a condition involving bulging sacs in the wall of the small bowel. Diverticula can occur in any portion of the gastrointestinal (GI) tract. They are much less common in the small bowel than in the colon (large intestine).

Diverticula in the large intestine are commonly referred to as colonic diverticular disease. According to a 2009 study, the prevalence of diverticula of the small bowel is only 0.3% to 5% of all cases of diverticulosis (including cases of colonic diverticular disease).

Anatomy and Terminology

There are three segments of the small intestine (small bowel), including the duodenum, the jejunum, and the ileum. The most common part of the small intestine to be affected by diverticula is the duodenum (the first segment).

The function of the duodenum is to receive food from the stomach, in addition to bile and pancreatic juices from the gallbladder and pancreas. The duodenum works to mix and churn the food and begin the process of breaking down nutrients (such as fats) for absorption.

Most nutrient absorption occurs in the mid-segment of the small intestine, called the jejunum, but a few nutrients—such as some B vitamins—are absorbed in the duodenum. 

To understand the subject of small bowel diverticula, it’s important to be aware of a few anatomical terms.

• Jejunum: The second segment of the small intestine, its function is primarily to absorb nutrients (such as sugars, amino acids, and fatty acids).
• Ileum: This third section of the small intestine mostly serves to absorb B vitamins and anything else that is not absorbed in the jejunum.
• Diverticulum: This is a single area that involves an outpouching or bulging sac anywhere in the gastrointestinal system.
• Diverticula: This is the plural form of diverticulum, denoting several bulging sacs in the gastrointestinal system.
• Pancreas: The pancreas is a large glandular organ located behind the stomach. It produces pancreatic enzymes to break down fats in the duodenum.
• Pancreatic juice: This clear liquid secreted by the pancreas has many different types of enzymes.
• Common bile duct: This tube is part of a series of tubular structures that function to carry bile from the gallbladder, through the pancreas, and into the duodenum.
• Bile: Bile is a greenish-brown fluid that is made in the liver and stored in the gallbladder. Its function is to aid in digestion by breaking down ingested fats in the duodenum.
• The ampulla of Vater: Formed by the union of the pancreatic duct and the common bile duct, it functions to allow bile and pancreatic juice to flow into the duodenum.
• The periampullary region: This is the area around the ampulla of Vater.
• The sphincter of Oddi: This is the smooth muscle that surrounds part of the bile duct and pancreatic duct. The sphincter of Oddi functions to allow the flow of bile and pancreatic juices into the duodenum.

Types of Small Intestine Diverticula

There are several types of duodenal diverticula. Many are categorized according to where they are located in the gastrointestinal tract. These include extraluminal, intraluminal, and juxtapapillary diverticula.

Extraluminal Diverticula

Extraluminal diverticula protrude outside the wall of the duodenum. Most of these are located in the periampullary region.

Common complications of extraluminal diverticula include;

• Intestinal bleeding
• Diverticulitis (inflammation of the small bowel, with development of small bulges in weakened spots of the intestinal wall)
• Malabsorption of nutrients (due to bacterial infection with multiple diverticula)
• Duodenal obstruction (partial or complete blockage of the small bowel, which is very rare)

A serious condition that may result from extraluminal diverticula is perforation (a hole that can occur anywhere in the GI system). This hole or opening may result in a serious condition called sepsis. The common symptoms of a perforated bowel can include:

• Severe abdominal pain
• Fever and chills
• Nausea, vomiting, and diarrhea

Intraluminal Diverticula

Intraluminal diverticula protrude into the inside of the wall of the duodenum. These bulging sacs develop completely inside the opening of the tube-like structure of the duodenum. Intraluminal diverticula are rare; they are caused by a developmental abnormality and are considered congenital (present at birth).

Complications of intraluminal diverticula may include:

• Partial obstruction of the duodenum
• Intestinal bleeding
• Perforation of the small bowel

Juxtapapillary Diverticula

Juxtapapillary diverticula arise within 2 to 3 centimeters (cm) of the ampulla of Vater. The primary symptom is abdominal pain. Juxtapapillary diverticula may cause several complications, including:

• Pancreatitis: Inflammation of the pancreas
• Cholangitis: Inflammation of the bile ducts
• Choledocholithiasis: Bile duct stones, which can occur even after a gallbladder removal
• Oddi dysfunction: The inability of the sphincter of Oddi to normally contract and relax, resulting in obstruction of the flow of pancreatic secretions, which often leads to pancreatitis

Small Bowel Diverticula Symptoms

Often, there are no symptoms at all associated with small bowel diverticula. The most common symptoms of duodenal diverticula are non-specific pain in the upper stomach (epigastric) area and bloating.

Many other symptoms of small bowel diverticula are considered nonspecific, meaning that they could apply to several different abdominal conditions. The nonspecific symptoms include:

• Abdominal pain
• A feeling of fullness early on during a meal or snack
• Bloating
• Loud rumbling sounds caused by gas (commonly called stomach growling, formally called borborygmi)
• Intermittent diarrhea

Complications

The rate of complications from duodenal diverticula is high. In fact, according to a 2012 study, 10% to 12% of those with duodenal diverticulum experience complications, and 46% of those with jejunal diverticulum have complications.

There are several complications resulting from small bowel diverticula that are often the underlying cause of symptoms. Some common complications seen in those with small bowel diverticula include the following.

• Intestinal bleeding: Could result in anemia
• Diverticulitis: Inflammation of the small bowel as a result of diverticula
• Acute (quickly developing, severe) intestinal perforation
• Biliary disease: Such as biliary stones, which may cause pancreatitis
• Bacterial overgrowth: Can cause excess flatulence, bloating, or diarrhea
• Malabsorption problems
• Intestinal obstruction: Caused by the diverticula blocking the intestine or from small bowel volvulus (a torsion or abnormal looping of the intestine) that blocks the passage of food from properly moving through the digestive system
• An abscess in the local area of the diverticulum

Causes

The exact cause of diverticula is unknown, but it is thought that they develop in response to abnormal movement of the intestine (called intestinal dyskinesis), very high pressure inside of the intestine (such as inside the colon). and abnormal contractions of the intestinal muscles (called peristalsis).

Peristalsis is the method by which food moves along the gastrointestinal tract from the esophagus (once it is swallowed) through the duodenum, into the colon and, finally to the anus, where waste is expelled.

Diagnosis

Diagnosing small bowel diverticula may be very challenging, depending on your symptoms and complications. Here are the diagnostic measures often taken when diagnosing abdominal pain and other, related symptoms.

• A complete physical examination evaluates symptoms such as abdominal fullness, tenderness, rectal bleeding, or presence of blood in the stool (called melena).
• Imaging tests may begin with an upper GI barium series (barium is a white chalky substance that is swallowed to enhance the ability to clearly view X-ray images).
• Other imaging tests include an upper endoscopy (involving a flexible tube with a tiny camera used to view the upper digestive system, including the duodenum), computerized tomography (CT) scans, magnetic resonance imaging (MRI), or capsule endoscopy. The capsule endoscopy procedure involves a very small camera placed inside a vitamin sized capsule that you swallow. One the capsule is swallowed, it takes pictures of the digestive tract.

Differential Diagnoses

There are several diagnoses with similar signs and symptoms that may be considered. Examples include:

• Perforated neoplasm (abnormal growth)
• Small bowel ulceration
• Large polyps (small growths protruding from a mucous membrane)

Treatment

For those with no symptoms, conservative treatment is often recommended for small bowel diverticula. Conservative treatment may include encouraging intake of fluids and the use of bulk-forming agents (such as fiber and bran and cellulose supplements). A high-fiber diet may be recommended to improve the motility of the GI system.

The condition will be monitored for any changes. Depending on the complications and symptoms, more aggressive treatment may include:

• Antibiotics (for bacterial overgrowth)
• Hospitalization (for complications such as severe bleeding)
• Endoscopic treatment (involving removal of the diverticula during an endoscopic procedure)

Treatment of Complications

Treatment for symptoms of small bowel diverticula complications may include the following.

• Diverticulitis: Hospitalization, bed rest, no foods or liquids by mouth, nasal suction, intravenous fluids, antibiotics, surgical consultation (to see if surgery is warranted), and more
• GI bleeding or hemorrhage: IV fluids and blood may need to be given; medications to constrict the blood vessels and slow bleeding (called vasoconstrictors) may be given for persistent bleeding
• Intestinal perforation: Requires early surgery, fluid and electrolyte management, and antibiotics
• Intestinal obstruction: Hospitalization, bed rest, no foods or liquids by mouth, nasal suction, IV (intravenous) fluids, antibiotics, and immediate surgical consultation to evaluate the need for emergency surgery
• Malabsorption: May be a response to bacterial overgrowth (which responds to antibiotics) or an obstruction (which improves once the obstruction is removed/treated)
• Flatulence and bloating: May be caused by bacterial overgrowth; responds most of the time to antibiotic therapy

A Word From Verywell

There are several complications of small bowel diverticula that require emergency surgery, including:

• Severe diverticulitis
• Intestinal perforation
• Intestinal obstruction
• Hemorrhage (that persists after initial treatment)

It’s vital to seek medical intervention if you have any symptoms of complications of small bowel diverticula.