Disease associated with gastrointestinal tract and its treatment Imtiaj Hossain Chowdhury B’Pharm (Jahangirnagar University), M’Pharm (Jahangirnagar University) Master’s in Public Health (American International University Bangladesh)

1. Disease associated with gastrointestinal tract and its treatment
Imtiaj Hossain Chowdhury
B’Pharm (Jahangirnagar University), M’Pharm (Jahangirnagar University)
Master’s in Public Health (American International University Bangladesh)

2. Gastrointestinal Tract:
The gastrointestinal tract (GIT) consists of a hollow muscular tube starting from the oral cavity,
where food enters the mouth, continuing through the pharynx, oesophagus, stomach and intestines
to the rectum and anus, where food is expelled. There are various accessory organs that assist the
tract by secreting enzymes to help break down food into its component nutrients. Thus, the salivary
glands, liver, pancreas and gall bladder have important functions in the digestive system. Food is
propelled along the length of the GIT by peristaltic movements of the muscular walls.
Figure: Anatomy of gastrointestinal tract
Functions of gastrointestinal tract:
The primary purpose of the gastrointestinal tract is to break food down into nutrients, which can
be absorbed into the body to provide energy. First food must be ingested into the mouth to be
mechanically processed and moistened. Secondly, digestion occurs mainly in the stomach and
small intestine where proteins, fats and carbohydrates are chemically broken down into their
basic building blocks. Smaller molecules are then absorbed across the epithelium of the small
intestine and subsequently enter the circulation. The large intestine plays a key role in
reabsorbing excess water. Finally, undigested material and secreted waste products are excreted

3. from the body via defecation (passing of faeces).
In the case of gastrointestinal disease or disorders, these functions of the gastrointestinal tract are
not achieved successfully. Patients may develop symptoms of nausea, vomiting, diarrhoea,
malabsorption, constipation or obstruction. Gastrointestinal problems are very common and most
people will have experienced some of the above symptoms several times throughout their lives.
Basic structure of gastrointestinal tract
The gastrointestinal tract is a muscular tube lined by a special layer of cells, called epithelium. The
contents of the tube are considered external to the body and are in continuity with the outside world
at the mouth and the anus. Although each section of the tract has specialized functions, the entire
tract has a similar basic structure with regional variations.
Figure: Basic structure of gastrointestinal tr

4. The wall is divided into four layers as follows:
Mucosa
The innermost layer of the digestive tract has specialized epithelial cells supported by an
underlying connective tissue layer called the lamina propria. The lamina propria contains blood
vessels, nerves, lymphoid tissue and glands that support the mucosa. Depending on its function,
the epithelium may be simple (a single layer) or stratified (multiple layers). Areas such
as the mouth and oesophagus are covered by a stratified squamous (flat) epithelium so they can
survive the wear and tear of passing food. Simple columnar (tall) or glandular epithelium lines
the stomach and intestines to aid secretion and absorption. The inner lining is constantly shed
and replaced, making it one of the most rapidly dividing areas of the body! Beneath the lamina
propria is the muscularis mucosa. This comprises layers of smooth muscle which can contract to
change the shape of the lumen.
Submucosa
The submucosa surrounds the muscularis mucosa and consists of fat, fibrous connective tissue
and larger vessels and nerves. At its outer margin there is a specialized nerve plexus called the
submucosal plexus or Meissner plexus. This supplies the mucosa and submucosa.
Muscularis externa
This smooth muscle layer has inner circular and outer longitudinal layers of muscle fibres
separated by the myenteric plexus or Auerbach plexus. Neural innervations control the
contraction of these muscles and hence the mechanical breakdown and peristalsis of the food
within the lumen.
Serosa/mesentery
The outer layer of the GIT is formed by fat and another layer of epithelial cells called
mesothelium.
Disease associated with gastrointestinal tract and its treatment
1. Celiac Disease
Sometimes called sprue or gluten-sensitive enteropathy (GSE), celiac disease is a hereditary,
gastrointestinal disorder caused by an autoimmune reaction to gluten. Gluten is a class of
proteins found in grains such as barley, rye, wheat, and their hybrids. When a person with

5. celiac disease consumes gluten, it triggers a negative immune reaction which destroys villi,
small hair-like projections on the inner wall of the small bowel. When the villi are destroyed,
the small intestine is unable to effectively
absorb vitamins, minerals and other
micronutrients from food. This results in
malnutrition and can lead to a plethora of
serious health problems, including
infertility, permanent damage to the small
bowel, and even ulcer colitis. The
pathogenesis of disease involves
interactions between environmental,
genetic, and immunologic factors.
The prevalence of celiac disease in the US population is estimated to be around 1 percent.
That means for every 100 Americans, one person has celiac disease.
Symptoms of celiac disease involve the digestive system, but they can also be seen in other
areas of the body. Some people may not show symptoms at all. It’s worth noting, however,

6. that adults and children often exhibit different symptoms. For example, celiac children may
be smaller in stature, experience delayed puberty, and often feel irritable and tired. Digestive
symptoms shown by children with celiac disease include awful-smelling stool, diarrhea,
constipation, stomach pain, abdominal bloating, vomiting, and weight loss. Adults, on the
other hand, can have both digestive and non-intestinal symptoms. On top of the usual
gastrointestinal symptoms, they may have seizures, fatigue, joint pain, iron-deficiency, skin
rashes, irregular menstruation, miscarriage, infertility, weak bones, and tooth discoloration.
Treatment: Celiac disease has no known cure. Following a strict no-gluten diet is the only
way to stop or even reduce these symptoms. If a person has dermatitis herpetiformis,
medications such as diamino diphenyl sulfone (Dapsone) can reduce the symptoms. This does
not heal the intestine, however, so a gluten-free diet is still crucial. Multivitamin
supplementation and therapy may help complement this lifelong gluten-free diet.
2. Irritable Bowel Syndrome (IBS)
Sometimes referred to as nervous stomach, irritable colon, mucous colitis or spastic colon,
Irritable Bowel Syndrome (IBS) is a group of gastrointestinal conditions in which the muscles
of the large intestine contract more frequently than normal. Contrary to common
misconception, this condition is not the same as Inflammatory Bowel Disease (IBD), a set of
digestive disorders that cause extended inflammation of the gastrointestinal tract. Irritable
Bowel Syndrome affects 3-20 percent of the US population. Traditionally, IBS has been
conceptualized as a condition of visceral hypersensitivity (leading to abdominal discomfort or
pain) and gastrointestinal motor disturbances (leading to diarrhea or constipation). Some of the
risk factors include being stressed and consumption of certain medicines and foods. Women
are more susceptible to IBS than men.

7. Symptoms of irritable bowel syndrome vary in duration and frequency from one person to
another. Some people have mild symptoms, while others experience substantial symptoms that
can affect their quality of life. Common symptoms of IBS include abdominal bloating, excess
gas, stomach cramps and pain, as well as alternating diarrhea and constipation. Most people
also notice changes in bowel movement, including looser or harder stools that come more
frequently than usual.
Treatment options for IBS include:
Eating a diet with more fiber
Avoiding stress, or learning ways to cope with stress
Working with a dietician or gastroenterologist to figure out which foods trigger your IBS so
that you can avoid them.
Staying away from coffee and other sources of caffeine
3. Constipation
Constipation is a digestive condition in which the person experiences hard, dry and often
painful bowel movements. Constipation is one of the most common digestive disorder
symptoms, and is estimated to affect approximately 2.5 million Americans.

8. This condition is typically caused by a low fiber diet, dehydration, certain meds, or anything
that disrupts your normal diet/routine. When you’re constipated, you tend to strain when
passing stool, sometimes causing hemorrhoids and anal fissures.
Some of the symptoms of constipation include abdominal bloating and pain, passing dry and
hard stools, straining when going, rectal blockage, and having fewer than 3 bowel movements
per week. In many cases, constipation can be treated by:
Increased fiber and water intake
Frequent exercise
Not ignoring urges of bowel movements
If the constipation persists, you can use laxatives as a temporary relief. It’s worth keeping in
mind that excessive use of laxatives can do more harm than good to your constipation.
4. Chronic Diarrhea
Chronic diarrhea is a gastrointestinal condition in which the person passes watery, mushy or
loose stools that lasts for weeks on end. In a 2018 study, researchers found that the prevalence of
chronic diarrhea in the US is 6.6 percent. This means that for every 100 Americans, 6 to 7 suffer
from the condition. Watery, loose stools that go on for more than 4 weeks is the main
manifestation of chronic diarrhea. You may feel the urge to move bowels frequently. Other
common symptoms include nausea, bloating and abdominal cramps.

9. Doctor can choose the best treatment option based on the underlying cause of diarrhea. It may
include corticosteroid, antibiotics, pain killers, immunosuppressants, antidiarrheal, and other
prescription medication. A diet and lifestyle change may also help reduce symptoms of chronic
diarrhea. These can include reducing meal portions, drinking plenty of water, eating lower fiber
foods, and avoiding caffeine and alcohol.
5. Gastroesophageal Reflux Disease (GERD)
Gastroesophageal reflux disease (GERD) is defined as having symptoms of acid reflux twice or
more times a week. Acid reflux or heartburn occurs when stomach contents and acids spill over
into your esophagus, causing a burning sensation and chest pain. This condition is sometimes
called gastroesophageal reflux or acid regurgitation. Around 20 percent of Americans are
affected by Gastroesophageal Reflux Disease, according to the National Institute of Diabetes
and Digestive and Kidney Diseases (NIDDK).
If not treated early, frequent bouts of heartburn can damage the esophagus and lead to other
serious health complications. GERD usually manifests itself as a dry cough, discomfort in the
chest area, sore throat, swallowing difficulties, and sour taste in the mouth, just to mention a few
symptoms.

10. You can treat GERD by:
● Taking over-the-counter antacids to treat heartburn
● Using proton pump inhibitors and H2 receptor blockers
If these medications don’t work, surgery to tighten the stomach muscles may be carried out.
This is especially the case if lifestyle changes and medication haven’t gotten rid of the
symptoms.
6. Ulcerative Colitis
Ulcerative colitis is one of the two most common inflammatory bowel diseases (IBD); Crohn’s
disease (more on this condition ahead) being the other one. This diagnosis refers to a group of
digestive disorders that cause inflammation of the gastrointestinal (GI) tract. Ulcerative colitis is
caused by the inflammation of the inner lining of the colon (large intestine), rectum or both.
Ulcers or small sores start to develop, typically starting in the rectum and spreading to the large
intestine. It is estimated that about 750,000 people in the United States have ulcerative colitis,
which is frequently diagnosed in individuals aged between 15 and 35. Genetic predisposition,
the presence of other immune disorders, and environmental factors such as antigens, viruses,
and bacteria may increase your chances of developing ulcerative colitis.

11. The most common symptoms of the condition include fever, diarrhea, malnutrition, weight loss,
bloodstains in stool, stomach pain, and frequent abdominal sounds. People with UC may also
exhibit other symptoms that include inflamed eyes, mouth sores, skin issues, loss of appetite,
swelling in the joints, and joint pain. The best course of treatment is usually prescription meds
such as mesalamine, sulfasalazine, balsalazide or olsalazine to help reduce swelling and
inflammation.
The doctor may also prescribe antibiotics, corticosteroids, and other drugs that may aid in
suppressing immune function. Or, biologic medications that help block inflammation.
7. Gallstones
Gallstones are what they sound like — stone-like lumps that develop in the bile ducts or
gallbladder. They can be as small as a grain of sand or as large as a golf ball. The gallbladder is
a small digestive organ located in the right upper abdomen. Its job is to produce, store and
release bile, a yellowish-green fluid that aids in the digestion of fat. This condition is fairly
common in the US, affecting 10-15 percent of the general population. Even though the exact
cause is not well known, gallstones usually form when bile has a high concentration of bilirubin
and cholesterol.

12. Gallstones may show no symptoms, although most people experience pain in the upper right
abdomen, especially when they consume fatty foods. Other symptoms of gallstones include
indigestion, diarrhea, burping, abdominal pain, dark urine, vomiting, nausea, and clay-colored
stool. People with mild symptoms may not need treatment. Depending on symptoms, surgery
may be recommended to get rid of the gallstones. About 250,000 Americans diagnosed with
gallstones undergo surgery each year.
Endoscopy is usually chosen if the gallstones are lodged in the bile ducts.
8. Crohn’s Disease
Crohn’s disease is a chronic digestive disease in which the ileum (the lower side of the small
bowel) becomes ulcerated and inflamed. Along with ulcerative colitis, this condition is part of a
larger group of gastrointestinal disorders called inflammatory bowel disease (IBD).
Although the inflammation primarily affects the ileum, ulceration can also occur in any area
of the small intestine, colon, esophagus, or stomach. Crohn’s disease is quite rampant in those
aged between 15 and 30, although it can develop at any age. According to the Crohn’s & Colitis
Foundation, around 780,000 individuals in the U.S. have Crohn’s disease.
As with any IBD, Crohn’s disease manifests itself gradually; some symptoms usually get
worse as the condition progresses. In the early stages of the condition, you may experience
fever, weight loss, reduced appetite, fatigue, bloody stools, abdominal cramps, and diarrhea.
You may also feel like going frequently. Potentially serious symptoms appear much

13. later. These can include: ulcers, skin inflammation, perianal fistulas, and shortness of breath as
a result of anemia.
Early screening and diagnosing can make a huge difference so you can start treatment.
Talking of treatment, your options are three-pronged:
Medication – You may need to take medications such as antidiarrheal drugs, anti-
inflammatory drugs, immunomodulators, antibiotics, and biologics to block inflammation.
Change in diet – Your doctor, dietician or gastroenterologist can suggest the best diet
changes to prevent Crohn’s flare-ups.
Surgery – This is a last-resort treatment option if lifestyle changes and medications don’t
work. However, three-quarters of people with Crohn’s disease usually undergo elective
surgery at one point or the other.
9. Chronic Pancreatitis
Chronic pancreatitis is a progressive condition characterized by an inflamed pancreas that
doesn’t heal and gets worse over time. Ultimately, the inflammation renders the pancreas
unable to produce digestive hormones. Unlike acute pancreatitis which lasts for a short time,
chronic pancreatitis occurs gradually and the inflammation doesn’t improve over months or
even years. The rate of incidence of chronic pancreatitis in the US is 50 for every 100,000
people in the general population.

14. Because the condition is progressive, the patient might not notice any symptoms of chronic
pancreatitis. When they do appear, symptoms may include diarrhea, fatty, loose pale stool,
upper abdominal pain, vomiting and nausea, shortness of breath, sudden weight loss, and
excessive fatigue and thirst. As the disease becomes very advanced, more serious symptoms
may appear, including intestinal blockage, internal bleeding, jaundice (yellowing of the skin
and eyes), and much more.
Treatment options include
Medication – The doctor may prescribe a blend of medications that include artificial
digestive enzymes, steroids, insulin, and pain medications.
Surgery – Although it is rare, surgery may be recommended if you have serious pain that
doesn’t respond to medication.
Endoscopy – An endoscope is a tiny, long tube used to clear blockages and relieve pain
associated with CP.
10. Diverticulitis
Diverticulitis is a serious type of diverticular disease, a set of conditions that affect the digestive
system. Diverticulosis is another type of diverticular disease. Diverticulosis is characterized by
the formation of small pockets or pouches called diverticula in the lower part of the inner lining
of the colon (the large intestine). One or several of these small pouches (diverticula) can become
inflamed, swollen with waste and get infected,
causing diverticulitis. This can lead to a range of mild to serious complications, including
rectal bleeding. Diverticulitis occurs in severe or advanced diverticular disease.

15. Potential symptoms include fever and chills, nausea and vomiting, painful abdominal cramps,
bloody stool, and rectal bleeding.
Diverticulitis can be treated in several ways, including:
Changes in diet – Your physician may get you on a liquid-only diet before weaning in low-
fiber foods after several days.
Medication – You could be prescribed OTC pain medication for discomfort, as well as
antibiotics if you have got an infection
Surgery – This rare option is recommended if your diverticulitis cannot be treated through
medication and dietary changes. These may include needle drainage, bowel resection with
colostomy or anastomosis.
11. Liver Disease
The liver is the second largest organ and plays a varied role in digestion, including breaking
down of food, storing energy, and getting rid of waste and toxins from the bloodstream. Liver
disease is a collective term for all digestive conditions that affect the liver. While the causes may
be different, they can all destroy your liver and affect its function. According to statistics from
the CDC, 1.8 percent of US adults have been diagnosed with liver disease, which translates to
about 4.5 million Americans.
Symptoms of liver disease can vary from one person to another, depending on the
cause. Some general symptoms may include: itchy skin, persistent fatigue, vomiting, nausea,
swollen abdomen, legs or ankles, dark urine, jaundice, loss of appetite, and black or bloody
stool.
Lifestyle changes are usually recommended for liver disease. These may include keeping a
healthy weight, reducing/avoiding alcohol, drinking plenty of water, and embracing a liver-
friendly diet. Depending on the underlying cause, the doctor might prescribe medications such as
antibiotics, blood pressure drugs, steroids, antiviral drugs, and multivitamins. On rare occasions,
you may need surgery to remove diseased parts of the liver. A liver transplant may be necessary
if no other treatment option is viable.

16. 12. Peptic Ulcer Disease
Peptic Ulcer Disease (PUD) is a gastrointestinal condition in which ulcers or painful sores
develop in the inner lining of the stomach and duodenum (the first portion of the small
intestine). The stomach lining is usually protected from corrosion by digestive juices by a thick
mucus layer. Peptic ulcers occur when this protective layer is reduced. Several factors can
cause a reduction in the mucus layer, including infection, long-term use of certain medications
and aging.
PUD affects approximately 4.5 million Americans, translating to a prevalence of around 1.4
percent.
Mild symptoms of PUD include acid reflux, vomiting or nausea, bloating, and burning
sensations in the upper abdomen. In a serious case of peptic ulcer disease, you may
experience heavy vomiting, severe pain in the upper stomach, black stool, and weight loss.
A healthful diet and prescription drugs can help treat most peptic ulcers. Depending on the
underlying cause, you may be prescribed proton pump inhibitors, antibiotics, probiotics or H2
receptor blockers. In rare cases, however, the doctor may recommend surgical removal of the
ulcers.
13. Lactose Intolerance
Lactose intolerance is a disorder in which a person is unable to digest lactose, a simple
carbohydrate present in milk and other dairy products. This is due to low levels of an enzyme
called lactase that is responsible for digesting lactose. Lactose intolerance is a very common
condition; it is estimated to affect about 75 percent of the American population. Symptoms can
range from mild to distressing and are experienced when dairy products are consumed. Lactose
intolerance can lead to an array of serious digestive problems. Diarrhea, gas, abdominal cramps
and bloating are the most common symptoms, but some patients may experience pain in the
lower abdomen, vomiting, nausea, and occasional constipation. Some treatments for lactose
intolerance include enzyme supplements to help break down lactose; lactose exposure to
acclimatize the body to the carbohydrate; and an assortment of prebiotics and probiotics.