What Are 5 Common Diseases of the Digestive System?

Common digestive disorders include irritable bowel syndrom (IBS), inflammatory bowel disease (IBD), gastroesophageal reflux disease (GERD or chronic heartburn), celiac disease, and diverticulitis.

Five common diseases of the digestive system include:

• Irritable bowel syndrome (IBS) 
  • IBS is a "functional" disorder, because changes in the functioning of the digestive system cause the collection of symptoms referred to as IBS. IBS is a problem with the movement (motility) of the digestive tract rather than a result of damage to the tissues of the digestive system. 
• Inflammatory bowel disease (IBD) 
  • IBD refers to two conditions (Crohn’s disease and ulcerative colitis) characterized by chronic inflammation of the gastrointestinal tract that results in damage to the GI tract.
• Gastroesophageal reflux disease (GERD) 
  • Acid reflux is a condition in which the acid from the stomach backs up into the esophagus, which is the tube that carries food from the mouth to the stomach. When acid reflux occurs more than twice weekly, is chronic, or causes uncomfortable symptoms or damage, it is considered to be gastroesophageal reflux disease (GERD).
• Celiac disease
  • Also called gluten-sensitive enteropathy, celiac sprue, or non-tropical sprue, celiac disease is an autoimmune condition in which the immune system responds abnormally to a protein called gluten, leading to damage of the lining of the small intestine, which is responsible for absorbing food and nutrients. Damage to the lining of the small intestine can lead to malabsorption. Gluten is a protein found in wheat, rye, barley, and many prepared foods. 
• Diverticulitis
  • This is a form of diverticular disease, which occurs when small pouches in the large intestinal (colonic) wall called diverticula, are present. These diverticula arise in the colon and push through weak spots in the colon’s outer muscle layers. Inflammation of the diverticula is called diverticulitis. Diverticular disease that is not inflamed is called diverticulosis. 

Symptoms of irritable bowel syndrome (IBS) include: 

• Abdominal pain, often accompanying to bowel movements
• Changes in bowel movements, which may be diarrhea, constipation, or both, depending on the type of IBS 
• Bloating
• Feeling as if a bowel movement is incomplete
• Whitish mucus in the stool

Symptoms of inflammatory bowel disease (IBD) include: 

• Persistent diarrhea
• Abdominal pain
• Rectal bleeding/bloody stools
• Weight loss
• Fatigue

Symptoms of gastroesophageal reflux disease (GERD) include:

• Heartburn
• Acid and undigested food back up into the throat or mouth (regurgitation)
• Stomach pain
• Chest pain
• Difficulty swallowing
• Feeling as if food is stuck in the throat
• Hoarseness/changes in voice
• Sore throat
• Unexplained dry cough
• Belching 
• Nausea 
• Vomiting (may be bloody)
• Bloating
• Bloody or black stools
• Unexplained weight loss
• Wheezing
• Bad breath
• Hiccups
• Breathing problems
• Tooth erosion

Symptoms of celiac disease include:

• Diarrhea
• Weight loss
• Abdominal discomfort
• Excessive gas
• Bloating
• Constipation
• Signs and symptoms caused by vitamin and nutrient deficiencies 

Symptoms of diverticulitis include:

• Abdominal pain (most commonly in the left lower quadrant, may be severe)
• Nausea
• Vomiting
• Constipation (may be severe)
• Diarrhea
• Blood in the stool
• Fever
• Chills
• Gas (flatulence)
• Bloating
• Rectal bleeding (rare)

The cause of irritable bowel syndrome (IBS) is unknown but the brain-gut interaction (how the brain and gut work together) is thought to play a role.

Different factors may play a role in causing IBS, including: 

• Genetics
• Bacterial infections in the digestive tract
• Small intestinal bacterial overgrowth (SIBO)
• Food intolerances or sensitivities
• Stressful or difficult early life events, such as physical or sexual abuse 
• Mental disorders such as depression, anxiety, and somatic symptom disorder 

The cause of inflammatory bowel disease (IBD) is unknown, but it is thought to be the result of a defective immune system. In IBD, the immune system responds incorrectly to environmental triggers, which results in inflammation of the gastrointestinal tract. There also seems to be a genetic component; people who have with a family history of IBD are more likely to develop this inappropriate immune response.

Gastroesophageal reflux disease (GERD) occurs when the lower esophageal sphincter becomes weak or relaxes, causing stomach contents to back up into the esophagus. 

Causes of lower esophageal sphincter weakness or relaxation include:

• Overweight or obesity, which puts increased pressure on the abdomen 
• Pregnancy, which also increases pressure on the abdomen
• Hiatal hernia 
• Smoking or inhaling secondhand smoke
• Certain medicines
• Alcohol use 
• Laying down after eating
• Scleroderma

The cause of celiac disease is unknown but it is believed to be a result of a combination of environmental and genetic factors. Celiac disease is more common in Europe, North and South America, Australia, North Africa, the Middle East, and in South Asia, and occurs rarely in people from other parts of Asia or sub-Saharan Africa.

The cause of diverticulitis in Western countries is believed to be due to a high-fat and low-fiber diet. 

Other possible causes of diverticulitis include: 

• Straining to have a bowel movement from constipation 
• Obesity
• Lack of exercise
• Smoking
• Genetics
• Use of certain medications including nonsteroidal anti-inflammatory drugs (NSAIDs) such as aspirin, and steroids

Diseases of the digestive system are diagnosed with a patient history and a physical exam. Other tests that may be used to diagnose a specific condition or rule out other conditions include: 

• Blood tests 
  • Complete blood count (CBC)
  • Lipid levels (total cholesterol, HDL, LDL, and triglycerides)
  • Thyroid levels
  • Antibody levels 
  • Nutritional deficiencies 
  • Electrolyte assays 
  • Blood cultures 
  • Renal function tests
  • Liver enzyme and lipase levels 
• Urinalysis 
• Urine culture 
• Stool tests to check for blood in the stool or other signs of infections or diseases
• Hydrogen breath test to check for other causes of digestive problems such as small intestinal bacterial overgrowth (SIBO) or problems with carbohydrate digestion, such as lactose intolerance
• Upper GI endoscopy with a biopsy 
• Small intestine biopsy 
• Esophageal pH and impedance monitoring
• Esophageal manometry 
• Colonoscopy 
• Imaging studies 
  • Contrast radiography
  • Magnetic resonance imaging (MRI)
  • Computed tomography (CT)
• Bone density (DEXA) scan 
• Computed tomography (CT) scanning of the abdomen 
• Lower GI series (barium contrast enema, using water-soluble medium)
• Abdominal radiographic (X-ray) series
• A pregnancy test for females of childbearing age with abdominal pain

Irritable bowel syndrome (IBS) is treated with: 

• Dietary changes: adding fiber, avoiding gluten, following a low FODMAP diet
• Lifestyle changes: increasing physical activity, practicing stress reduction techniques, getting adequate sleep
• Medications used to treat IBS with diarrhea (IBS-D) may include:
  • Loperamide (Imodium)
  • Rifaximin (Xifaxan) 
  • Eluxadoline (Viberzi) 
  • Alosetron (Lotronex), only for women to be used with special warnings and precautions

Medications used to treat IBS with constipation (IBS-C) may include:

• Fiber supplements
• Laxatives
  • Lubiprostone (Amitiza) 
  • Linaclotide (Linzess) 
  • Plecanatide (Trulance) 
• Other medications used to treat abdominal pain associated with IBS may include:
  • Antispasmodics
  • Antidepressants 
  • Coated peppermint oil capsules 

Inflammatory bowel disease (IBS) is treated with: 

• Aminosalicylates
• Corticosteroids (such as prednisone)
• Immunomodulators
• Biologics
• Vaccinations to prevent infections
• Surgery in severe cases to remove damaged portions of the gastrointestinal tract

Gastroesophageal reflux disease (GERD) can be managed in some cases lifestyle changes or by taking non-prescription medicines to decrease the effects of stomach acid. 

Home remedies to relieve gastroesophageal reflux disease (GERD) include:

• Lose weight if you are overweight or obese
• Raise the head of the bed 6 to 8 inches using blocks of wood or rubber under 2 legs of the bed or a foam wedge under the mattress
• Avoid foods that worsen symptoms such as coffee, chocolate, alcohol, peppermint, fatty or greasy foods, and spicy foods
• Avoid medications such as aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) that may aggravate GERD
• Take medications with plenty of water
• Don’t smoke
• Don’t overeat
• Don’t eat 2 to 3 hours before bed -- lying down with a full stomach can make reflux worse
• Wear loose clothing around the stomach area

If lifestyle changes do not relieve symptoms GERD, medications to treat GERD include: 

• Antacids
• Histamine blockers
• Proton pump inhibitors (PPIs)
• Prokinetics
• Antibiotics

Surgery is used to treat severe cases of GERD.

The foundation of treatment for celiac disease is a gluten-free diet. Gluten is a group of proteins found in wheat, rye, and barley, and is also a hidden ingredient in many processed and prepared foods as well as medications and supplements. 

A dietitian knowledgeable about celiac disease can help patients learn about a gluten-free diet, what foods to eat and what foods to avoid to maintain nutritional balance. They can also advise on any needed nutritional supplements. People with celiac disease must strictly adhere to a gluten free diet because even small amounts of gluten can trigger or worsen symptoms. 

Treatment for mild diverticulitis includes:

• Clear liquid diet for 2-3 days; progressing to a soft diet as tolerated
• 7-10 days of oral broad-spectrum antibiotics if needed
• Acetaminophen (Tylenol) and antispasmodics for pain

In severe cases hospitalization may be needed. Severe diverticulitis may result in a perforation of the colon wall which may lead to an infection called an abscess. If hospitalized, treatment for severe diverticulitis may include:

• Clear liquid diet; progress to a soft diet as tolerated
• Intravenous (IV) or oral antibiotics
• Abscesses less than 3 cm: Typically resolved with antibiotics 
• Abscesses greater than 4 cm: Drain percutaneously
• Pain management 
• Elective surgical resection