Gastritis

LECTURE

1. Gastritis
Gastritis is inflammation of the stomach lining.
It can occur suddenly (acute) or gradually
(chronic). Chronic gastritis occurs in two out of
every 10,000 people, whereas acute gastritis is
more common, occurring in eight out of every
1,000 people
Causes
Gastritis can be caused by many factors, including infection, injury,
certain drugs, and disorders of the immune system.
1-Infections with bacteria, viruses, or fungi can cause gastritis.
Worldwide, the most common cause of gastritis is infection
with Helicobacter pylori bacteria. Viral or fungal gastritis may
develop in people who have had a prolonged illness or an impaired
immune system, such as those who have AIDS or cancer or those who
take immunosuppressant drugs.
2-Erosive gastritis results from irritants such as drugs,
especially aspirin and other nonsteroidal anti-inflammatory drugs
(NSAIDs. Crohn's disease; bacterial and viral infections; and the
ingestion of corrosive substances. In some people, even a
baby aspirin taken daily can injure the stomach lining. Erosive
gastritis can develop suddenly but more commonly develops slowly,
usually in people who are otherwise healthy.
3-Acute stress gastritis, actually a form of erosive gastritis, is caused
by a sudden illness or injury. The injury may not even be to the
stomach. For example, extensive skin burns and injuries involving
major bleeding are typical causes. Exactly why serious illness can lead
to gastritis is not known but may be related to decreased blood flow
to the stomach or to impairment of the stomach lining's ability to
protect and renew itself.

2. 4-Radiation gastritis can occur if radiation is delivered to the lower
left side of the chest or upper abdomen, where it can irritate the
stomach lining.
5-Postgastrectomy gastritis occurs &is thought to result when
surgery impairs blood flow to the stomach lining or exposes the
stomach lining to an excessive amount of bile
6-Atrophic gastritis causes the stomach lining to become very thin
and to lose many or all of the cells that produce acid and enzymes.
This condition can occur when antibodies attack the stomach lining
(termed autoimmune metaplastic atrophic gastritis)
&with Helicobacter pylori bacteria.
7-Eosinophilic gastritis may result from an allergic reaction to an
infestation with roundworms. In other cases, the cause is unknown.
In this type of gastritis, eosinophils accumulate in the stomach wall.
8-Ménétrier's disease, whose cause is unknown, is a type of
gastritis in which the stomach wall develops thick, large folds;
enlarged glands; and fluid-filled cysts. The disease may be due to an
abnormal immune reaction and has also been associated
with Helicobacter pylori infection.
9- lymphocytic gastritis, lymphocytes (another type of white blood
cell) accumulate in the stomach wall and other organs. This
lymphocyte accumulation also occurs in celiac sprue (a malabsorptive
disorder), but the cause is frequently unknown
Symptoms and Complications
Gastritis usually causes no symptoms. When symptoms do occur,
they vary depending on the cause and may include pain or discomfort
(dyspepsia) or nausea or vomiting, problems that are often simply
referred to as indigestion. Gastritis can lead to ulcers, which may
cause the symptoms to get worse.

3. Nausea and intermittent vomiting can result from erosive gastritis,
radiation gastritis, Ménétrier's disease, and lymphocytic gastritis.
Dyspepsia can occur, especially with erosive gastritis, radiation
gastritis, postgastrectomy gastritis, and atrophic gastritis. Very mild
dyspepsia also occurs with acute stress gastritis.
Ulcers can develop with several types of gastritis, especially acute
stress gastritis, erosive gastritis, and radiation gastritis. Ulcers may
bleed, causing a person to vomit blood (hematemesis) or pass tarry
black stools (melena). Acute stress gastritis may lead to bleeding from
ulcers within a few days after an illness or injury, whereas bleeding
tends to develop more slowly in the case of erosive gastritis or
radiation gastritis. Persistent bleeding can lead to symptoms of
anemia, including fatigue, weakness, and light-headedness. If an
ulcer goes through (perforates) the stomach wall, stomach contents
may spill into the abdominal cavity, resulting in inflammation and
usually infection of the lining of the abdominal cavity (peritonitis)
and sudden worsening of pain
Some complications of gastritis are slow to develop. The scarring and
narrowing of the stomach outlet that can result from gastritis,
especially from radiation gastritis and eosinophilic gastritis, can
cause severe nausea and frequent vomiting. In Ménétrier's disease,
fluid retention and swelling of the tissues (edema) may occur because
of loss of protein from the inflamed stomach lining. About 10% of
people with Ménétrier's disease develop stomach cancer some years
later. Postgastrectomy gastritis and atrophic gastritis may cause
symptoms of anemia, such as fatigue and weakness, because of
decreased production of intrinsic factor (a protein that binds vitamin
B 12 , allowing the B 12 to be absorbed and used in the production of red
blood cells). A small percentage of people with atrophic gastritis
develop a condition called metaplasia, in which cells lining the
stomach change and become precancerous. In an even smaller
percentage of people, metaplasia leads to stomach cancer.

4. Diagnosis
A doctor suspects gastritis when a person has upper abdominal
discomfort or pain or nausea. Tests usually are not needed. However,
if the doctor is uncertain of the diagnosis, or if symptoms do not
resolve with treatment, an examination of the stomach using an
endoscope may be needed. If necessary, the doctor can perform a
biopsy (removal of a tissue sample for examination under a
microscope) of the stomach lining.
Treatment
Regardless of the cause of gastritis, symptoms can be relieved by
taking drugs that neutralize or reduce the production of stomach acid
and by discontinuing drugs that cause symptoms .
For mild symptoms, taking antacids, which neutralize acid that has
already been produced and released in the stomach, is often
sufficient. However, antacids have to be taken several times a day and
often produce diarrhea or constipation.
Drugs that reduce acid production include histamine-2 (H 2 )
blockers and proton pump inhibitors. H 2 blockers are usually more
effective than antacids in relieving symptoms, and many people find
them far more convenient. Proton pump inhibitors are prescribed
when the strongest treatment is needed. When infection is a part of
gastritis, antibiotics are also prescribed.
Doctors may prescribe sucralfate, which helps to prevent irritation.
When gastritis leads to ulceration that perforates the stomach wall,
immediate surgery is usually needed
People with erosive gastritis must avoid taking drugs that irritate the
stomach lining (such as NSAIDs). Some doctors prescribe proton
pump inhibitors or misoprostol to help protect the stomach lining.
The coxibs (COX-2 inhibitors such as celecoxib) are less likely to
irritate the stomach lining than the older NSAIDs, but studies have
shown that coxibs appear to increase the risk of heart attack and

5. stroke with long-term use. Therefore, caution should be taken with
use of coxibs.
Most people with acute stress gastritis recover fully when the
underlying illness, injury, or bleeding is controlled. However, 2% of
people in intensive care units have heavy bleeding from acute stress
gastritis, which is often fatal. Therefore, doctors try to prevent acute
stress gastritis after a major illness, major injury, or severe burn.
Drugs that reduce acid production are commonly given after surgery
and to people in most intensive care units to prevent acute stress
gastritis. These drugs are also used to treat any ulcers that form. For
people with heavy bleeding from acute stress gastritis, a wide variety
of treatments have been used. Few of these treatments, however,
improve the outcome. Blood transfusions may actually make bleeding
worse. Bleeding points can be temporarily heat-sealed (cauterized)
during an endoscopy, but bleeding often starts again if the underlying
illness persists. If bleeding continues, the entire stomach may have to
be removed as a lifesaving measur
There is no cure for postgastrectomy gastritis or atrophic gastritis.
People with anemia resulting from decreased absorption of vitamin
B 12 that occurs with atrophic gastritis must take supplemental
injections of the vitamin for the rest of their lives.
Corticosteroids or surgery may be needed to relieve a blocked
stomach outlet caused by eosinophilic gastritis.
Removing part or all of the stomach may cure Ménétrier's disease.
There is no effective drug treatment

6. stroke with long-term use. Therefore, caution should be taken with
use of coxibs.
Most people with acute stress gastritis recover fully when the
underlying illness, injury, or bleeding is controlled. However, 2% of
people in intensive care units have heavy bleeding from acute stress
gastritis, which is often fatal. Therefore, doctors try to prevent acute
stress gastritis after a major illness, major injury, or severe burn.
Drugs that reduce acid production are commonly given after surgery
and to people in most intensive care units to prevent acute stress
gastritis. These drugs are also used to treat any ulcers that form. For
people with heavy bleeding from acute stress gastritis, a wide variety
of treatments have been used. Few of these treatments, however,
improve the outcome. Blood transfusions may actually make bleeding
worse. Bleeding points can be temporarily heat-sealed (cauterized)
during an endoscopy, but bleeding often starts again if the underlying
illness persists. If bleeding continues, the entire stomach may have to
be removed as a lifesaving measur
There is no cure for postgastrectomy gastritis or atrophic gastritis.
People with anemia resulting from decreased absorption of vitamin
B 12 that occurs with atrophic gastritis must take supplemental
injections of the vitamin for the rest of their lives.
Corticosteroids or surgery may be needed to relieve a blocked
stomach outlet caused by eosinophilic gastritis.
Removing part or all of the stomach may cure Ménétrier's disease.
There is no effective drug treatment