What Is Diverticular Disease?
Diverticular disease is the general name given to the disease that
creates small sacs or pouches from the wall of the colon and the
complications that can arise from the presence of those sacs. There are
many terms related to diverticular disease that can be confusing and
deserve to be defined. The individual sacs or pouches are called a
diverticulum. Multiple sacs or pouches (the plural form of the
worddiverticulum) are called diverticula.

What Is Diverticulosis?
The term diverticulosis refers to simply having diverticula within the
colon but without complications or problems from those sacs. The
presence of diverticulosis can lead to several different complications
such as diverticulitis, perforation, stricture, fistula, and bleeding.
Which Part Of Colon Is Affected By Diverticulosis?
Diverticula can form throughout the colon but, in the United States and
other Western countries, the sigmoid colon is the most common site for
diverticula to form. Diverticula of the cecum and ascending colon are
seen occasionally in the United States but are much more common in Asia.
What Are The Causes of Diverticulosis?
The exact cause of diverticulosis is not known. The most commonly
accepted theory is that low amounts of fiber in a person’s diet causes
the stool to become dry, forcing the colon to create higher pressures to
move the stool through the colon. These high pressures cause the weakest
points of the colon wall to bulge out, especially at points where blood
vessels penetrate the wall of the colon. Along with the formation of
diverticula, higher colonic pressures may cause the muscles of the colon
wall to become enlarged, or hypertrophied.
Diverticulosis is very common, and the proportion of the population with
diverticulosis increases with age. It is uncommon for people under the
age of 30 to have diverticulosis, but approximately 30-40% of people
aged 60 years old have diverticulosis and up to 50-80% of people aged 80
years old have diverticulosis. Most people with diverticulosis will not
have symptoms from it. In fact, only 10-20% of people with
diverticulosis will develop symptoms, and of the people that develop
symptoms, only 10-20% of those people will need hospitalization and only
about 1% will require surgery.
What Are The Complications Of Diverticulosis?
Diverticulitis
The most common complication of diverticulosis is diverticulitis.
Diverticulitis is an inflammatory condition of the colon that is thought
to be caused by perforation of one of the individual sacs. It is
estimated that 10-20% of people with diverticulosis will develop
diverticulitis.
The most common symptoms of simple diverticulitis are abdominal or
pelvic pain, abdominal tenderness, and fevers. Complicated
diverticulitis occurs when secondary complications results after an
attack of diverticulitis, and these complications include abscess
formation and perforation of the colon with peritonitis. An abscess is a
pocket of pus that the body has walled off, and peritonitis is infection
that spreads freely within the abdomen. Peritonitis often causes
patients to become quite sick and may be life threatening.
Once a person has an attack of diverticulitis, he or she is at risk for
further episodes and for the development of complications. It is
difficult to define the exact risk of a recurrent attack of
diverticulitis in a person who has had a previous attack, and there are
many factors that may influence this risk, including the age of the
patient and the severity of the initial attack. The most feared
complication of diverticulitis is perforation and peritonitis, which
often requires emergency surgery and the creation of a colostomy.
Several studies have demonstrated that the vast majority of patients in
whom this happens have never had prior symptoms from their diverticula.

Stenosis/ Stricture/ Fistula
Other complications of diverticulosis include bleeding, formation of a
narrowing in the colon that does not easily let stool pass (called a
stricture), or formation of a tract to another organ or the skin (called
a fistula). When a fistula forms, it most commonly connects the colon to
the bladder. It may also connect the colon to the skin, uterus, vagina,
or another portion of the bowel.

Chronic Diverticulitis
Chronic diverticulitis is the condition where patients may have repeated
attacks of diverticulitis or may have a prolonged course of a single
attack of diverticulitis. Chronic diverticulitis also refers to the
complications that arise from repeated attacks of diverticulitis such as
stricture and fistula.
Bleeding
Finally, diverticular sacs can bleed. Bleeding may be minor in the form
of a small amount of red blood that is mixed in with the stool during an
attack of diverticulitis, or the bleeding may be severe, involving the
passage of dark clots of blood that may or may not happen during an
attack of diverticulitis. The treatment of diverticular bleeding differs
significantly from other forms of diverticular disease, Briefly, most
cases of bleeding will stop with supportive care in the hospital or with
minimally invasive techniques such as angiography or colonoscopy.
Who Is At Risk For Diverticular Disease?
A risk factor is something that increases a person’s chance of getting a
disease or problem. There are many risk factors for diverticular disease
including:
Low fiber diet. Diets that are low in fiber, fruits, and vegetables
and are high in red meat arerisk factors for developing diverticular
disease. A diet that lacks fiber may increase the risk by three
times, so adding fiber to your diet may help protect the colon from
diverticular disease. In the past, patients with diverticulosis were
told to avoid nuts, seeds, and popcorn, as it was felt that this may
increase the risk of diverticulitis, but more recent studies that
have found this recommendation not to be true.
Nonsteroidal anti-inflammatory drugs (NSAIDs). Use of NSAIDs such as
ibuprofen for conditions such as arthritis has been associated with
complications of diverticulosis.
Immune status. Patients whose immune systems are suppressed from
medications (steroids or anti-rejection medications for a
transplanted organ) are at risk for more severe complications such
as colonic perforation.
Alcohol. Excessive consumption of alcohol may raise the risk of
diverticulitis by 2-3 times as compared to the general population.
Age and gender. It is unclear the extent to which age and gender are
a risk factor for complications from diverticulosis. Women tend to
have complications from diverticulosis later in life than men. It
was once thought that patients who have an attack of diverticulitis
before age 50 would have a more virulent form of the disease, but
this does not seem to be the case.
What Are The Symptoms Of Diverticular Disease?
As mentioned, most patients with diverticulosis have no symptoms. The
most common symptoms of diverticulitis are abdominal pain and fever.
The abdominal pain of diverticulitis is usually lower and/or left-sided
abdominal pain. The pain is usually sharp and constant, and the pain may
seem to travel, or radiate, to the leg, groin, back, and side. A change
in bowel habits such as diarrhea or constipation may also be seen.
Patients may also have urinary symptoms such as increased need to
urinate and urinary urgency.
Patients with complications of their diverticulitis may have more
chronic or long-term, symptoms. Thin stools or constipation may indicate
the formation of a stricture. Dark, cloudy urine or passing air with the
urine may indicate the formation of a fistula to the bladder.
How Is It Diagnosed?
Diverticular disease and its complications are usually diagnosed through
the patient’s history and physical examination, often with the aid of
diagnostic tests. Symptoms such as abdominal pain and tenderness are not
specific to diverticulitis, and it is important to distinguish
diverticulitis from diseases that can involve other organs in the
abdomen such as the appendix, gallbladder, stomach, small bowel,
ovaries, uterus, prostate and bladder. A careful history and physical
can help narrow down the diagnosis or eliminate other diagnoses.
The most common tests to help make the diagnosis of diverticulitis and
its complications are blood tests, urine tests, and a CT scan of the
abdomen and pelvis. A CT scan is considered the “gold standard” for
diagnosing diverticulitis. It can show what part of the colon is
involved, and if there is any sign of abscess, stricture, or fistula.
Blood tests are often performed, and an elevated white blood cell count
may indicate the presence of infection. An analysis and culture of the
urine may detect a urinary tract infection, raising suspicion of a
fistula from the colon to the bladder, as the urine would be
contaminated with stool from the colon.
How Diverticular Disease Is Treated?
Diverticular disease can develop in many forms and patients may present
with various degrees of severity. As might be expected, there is no one
best treatment for all forms of diverticular disease. The following
discussion will attempt to describe various common treatments for
different ways people can present with diverticular disease.
Most people with diverticulosis will never develop problems from it.
Patients who are diagnosed with diverticulosis on a routine colonoscopy
or by other testing, and otherwise do not have symptoms of
diverticulitis, are advised to consider increasing the fiber in their
diet. Although the ideal amount of fiber to decrease diverticulitis
attacks or other problems from diverticulosis is not known, it is
generally recommended that people with diverticulosis consume about 20
30 grams of fiber per day people with diverticulosis consume about 20-30
grams of fiber per day.
When discussing the treatment options for diverticulitis, it is
convenient to separate treatment options into two categories: treatment
for acute diverticulitis and treatment for chronic diverticulitis.
Treatment for acute diverticulitis
Treatment for acute diverticulitis involves the treatment of a new and
ongoing attack of diverticulitis. Most patients with an acute attack of
diverticulitis will find relief with antibiotics and temporary changes
in diet. Most of these patients will not require hospitalization.
Patients without significant fever or change in heart rate or blood
pressure who can tolerate taking in oral liquids can be treated with
oral antibiotics and restriction of the diet to a low fiber or liquid
only diet until the attack resolves.
Patients who have signs of a more serious attack, such as high white
blood cell count, high fever, changes in heart rate or blood pressure,
or patients who do not get better with oral antibiotics, will have to be
admitted to the hospital for hydration and intravenous (IV) antibiotics.
A colonoscopy is often recommended several weeks after recovery from an
initial attack of diverticulitis to make sure there is not another cause
for recent illness (cancer or other inflammatory condition of the
colon).
Patients who have a severe attack of diverticulitis are at risk for
forming an abscess.An abscess is pocket of pus that results from rupture
of an inflamed diverticulum, and abscesses can be detected on CT scans.
Small abscesses may be treated with antibiotics alone, but larger
abscesses may require a procedure called “percutaneous drainage,“which
is a procedure that uses radiologic imaging to place a drain through the
skin into the abscess.
Surgical Treatment Of Acute Diverticulitis;
Surgery for acute diverticulitis is limited to a few circumstances.
These include:
An attack of diverticulitis that causes the colon to perforate,
resulting in pus or stool leaking into the abdominal cavity and
causing peritonitis.
Patients with colonic perforation are usually quite ill, and present
with severe abdominal pain and changes in heart rate and blood
pressure. These patients often require emergency surgery.
An abscess that cannot be safely drained with percutaneous drainage,
or if the percutaneous drainage was ineffective. The patient fails
to improve with appropriate medical therapy, including IV
antibiotics and hospitalization.
Aggressive treatment, including surgery, is often required for patients
who are immunocompromised (patients who have received an organ
transplant or who are receiving chemotherapy).
There are several surgical options for the treatment of acute
diverticulitis.
Laparoscopic (minimally invasive) or traditional open surgical
techniques may be used for all these options.
The options for surgical treatment include: removal of the involved part
of the colon, with or without creation of a colostomy, a washout of the
abdominal cavity and leaving the colon in place, or creating an ostomy
(a surgically created opening between an internal organ and the body
surface) to divert the fecal stream without removal of the colon.
Removal of the affected portion of the colon, usually the sigmoid colon,
is the most common procedure for surgical treatment of acute
diverticulitis. Once that portion of the colon is removed, the surgeon
must decide on whether to reconnect the colon to the rectum or create a
colostomy. A colostomy is a procedure where the end of the bowel is
brought out through the abdominal wall and the stool empties into a bag
that attaches to the skin.
Reconnecting the colon and avoiding an ostomy is a great advantage to
the patient. Reversal of a colostomy at a later date can be a
challenging procedure, and is associated with significant risks.
However, there is also a risk that reconnecting the colon may not heal
properly, resulting in a leak from the colon and ongoing infection. The
risk of leak is thought to be higher, 6-19% vs. 5%, when the patient is
acutely sick from diverticulitis.
In order to minimize the risks of colon leak, your surgeon may choose to
protect the reconnected bowel by bringing out a piece of small
intestine. This procedure, called a protective loop ileostomy, allows
the stool to pass out of the body and avoid the reconnected bowel as it
heals. After 2-3 months, the healing process of the bowel should be
complete and the ileostomy may be reconnected, removing the ostomy and
allowing stool to pass normally below. Your surgeon will evaluate the
risks involved with any of these scenarios, and then carefully consider
the option that is best for any particular patient.
An alternative strategy emerging only in recent years, for the treatment
of acute complicated diverticulitis, is to perform a laparoscopic
washout of the abdomen. This technique involves using laparoscopic
techniques to inspect the abdomen, drain any pus, and wash out the
abdominal cavity. The goal is to remove the infected fluid, place a
drain to control any additional effluent, allow the colon to heal, and
avoid surgically removing the involved portion of the colon, when
possible, in the acute setting or, in some cases, altogether. This
technique has most often been used for patients with an abscess or
perforation of the colon and spread of infection, but without spread of
stool into the abdomen.
The main criticism of this technique is that the inflamed section of
colon remains in place, putting the patient at risk for ongoing or
recurrent infection. This is a relatively new technique and compared to
traditional management strategies, the results as are not well defined.
Studies are underway to see if this technique has an appropriate role in
managing patients with diverticulitis.

Treatment of chronic diverticulitis
Treatment of chronic diverticulitis involves treatment of recurrent
disease, or the complications that may result from an acute attack. In
general, treatment for chronic diverticulitis involves surgery to remove
the involved portions of the colon, usually the sigmoid colon, and then
reconnecting the colon (see Figure 8). This operation may be done with
either laparoscopic or traditional open techniques. The main benefits of
laparoscopic surgery are a smaller incision size and a quicker recovery.
It is not necessary to remove all of the parts of the colon that have
diverticula. It is only necessary to remove the portion of the colon
that is diseased, and to ensure that the reconnection of the colon is
done between soft, non-diseased portion of colon and the rectum.
There are many risks associated with colon surgery. As discussed above,
there is a risk that the reconnection will not heal properly and the
colon can leak stool. Because an operation for chronic diverticulitis is
usually done electively, the risk of a colon leak is lower than if the
operation is performed in an emergency.
The most common risk associated with colon surgery is infection.Surgery
may result in a wound infection, which may be limited to the skin and
underlying fat, or may result in an infection that spreads within the
abdomen. Wound infections are treated by opening the wound and dressing
changes, but deeper infections are treated with antibiotics and either
percutaneous drainage or open operation.
The sigmoid colon lies directly over the left ureter, which is the tube
that carries urine from the kidney to the bladder. During surgery, there
is a risk that the left ureter may be injured while removing the sigmoid
colon, especially if there have been many attacks of diverticulitis. In
order to reduce this risk your surgeon may ask a urologist to place a
stent, or tube temporarily, in one or both of the ureters as part of
your operation in order to help identify, and avoid injury to, the
ureters during surgery.
Patients who undergo surgery are also at risk of a urinary tract
infection, because they often have a catheter to drain the bladder
during and after surgery. Other risks of surgery include, but are not
limited to, post-operative pneumonia, heart attack, stroke, blood clots
in the legs and some times in the lungs, organ failure, and even death.
Since there are significant risks associated with surgery, the benefits
obtained from surgery must outweigh the risks. The main benefits of
surgery for chronic diverticulitis are to prevent recurrent attacks, or
cure the complications of diverticulitis such as stricture or fistula.
A patient who has had an attack of diverticulitis is at risk for a
repeat attack. The risk of a repeat attack after an initial attack of
uncomplicated diverticulitis is low, with rates ranging widely from 1.4%
to 18%. The risk of a repeat attack increases with each subsequent
attack. It was previously thought that repeated attacks placed a patient
at risk for emergency surgery and need for a colostomy, therefore a
pre-emptive resection of the sigmoid colon, after the patient had
recovered and the patient was doing well, was often recommended to
prevent the need for emergency surgery.
It has since been found that the risk of needing emergency surgery after
an attack of uncomplicated diverticulitis is low. The severity of prior
attacks also affects the risk of future attacks. For example, patients
who had an acute attack with an abscess that was treated with a
percutaneous drain are at higher risk for recurrence.However, despite
this higher risk, there is evidence that some patients who have been
successfully treated for an abscess will do well without surgery.
Therefore, the decision to proceed with a colon resection to prevent
future attacks should be based on the number and severity of prior
attacks, the presence of ongoing symptoms from prior attacks, and the
age and general medical condition of the patient.
The indications for surgery are more definite when a stricture or
fistula forms as a result of diverticular disease.A stricture is a
narrowing of the colon that may partially block passage of stool. In
rare cases, the stricture may become so severe that it causes complete
obstruction (blockage) of the bowel. A fistula is an abnormal connection
from the colon to another organ. Fistulas may form to the bladder,
uterus, vagina, skin, or other portions of the bowel. Surgery for both
fistula and stricture includes removal of the sigmoid colon with
reconnection of the colon or creation of an ostomy, as described
above.Surgery for a fistula may also include a repair or resection of
the organ which is involved in the fistula. These procedures may involve
removal of an additional segment of bowel, repair of the bladder, repair
of the vagina, or repair of the uterus or hysterectomy (removal of the
uterus) in severe cases.

In summary, diverticular disease is a common condition, especially among
older adults. It may present with a wide range of symptoms and severity,
ranging from asymptomatic disease to life threatening abdominal
infections. There are several treatment strategies with the majority of
therapies consisting of conservative measures such as a change in diet
or antibiotics. Surgery may play a curative role, especially in more
advanced cases.