Diseases of the GI

Gastroesophageal Reflux Disease (GERD)

• Affects more than 20 million Americans daily and over 100 million occasionally.
• Symptoms arise from reflux of gastric contents into the esophagus or beyond.
• Common symptoms include heartburn, increased salivation, belching, and pain.
• Pain can be severe and is often worse when lying down.
• Multifactorial etiology involving both physical and lifestyle factors.

Lower Esophageal Sphincter (LES)

• Acts as a barrier between the esophagus and stomach.
• Normally maintains higher pressure in the esophagus than in the stomach to prevent reflux.
• Transient LES relaxations are normal but become problematic when LES incompetence develops.

Factors Contributing to LES Incompetence

• Increased secretion of hormones like gastrin, estrogen, and progesterone.
• Obesity.
• Presence of medical conditions like hiatal hernia.
• Cigarette smoking.
• Medications like morphine and theophylline.
• Specific foods including:
  • High-fat foods.
  • Chocolate.
  • Spearmint.
  • Peppermint.
  • Alcohol.
  • Caffeine.

Hiatal Hernia

• Out-pouching of the stomach into the chest through the esophageal hiatus of the diaphragm.
• The esophageal hiatus is an opening in the diaphragm through which the esophagus passes.

Complications of Untreated GERD

• Dysphagia (difficulty swallowing) and odynophagia (painful swallowing).
• Aspiration of gastric contents into the lungs leading to pneumonia.
• Esophagitis (inflammation of the esophagus).
• Esophageal erosion, ulceration, and perforation.
• Esophageal strictures and scarring.
• Dental corrosion and tooth surface loss.
• Barrett's esophagus (5-15%) - a change in esophageal mucosa cells that increases the risk of esophageal adenocarcinoma.

GERD Treatment: Medications

• Antacids - buffer gastric acid (e.g., Pepto-Bismol, Maalox, Mylanta).
• H2 antagonists - block histamine action on parietal cells, decreasing acid production (e.g., Pepcid, Zantac, Tagamet).
• Proton pump inhibitors (PPI) - inhibit acid secretion (e.g., Protonix, Prilosec, Nexium).
• Prokinetics - increase gastric emptying speed (e.g., Reglan, Erythromycin).
• Mucosal protectants.

GERD Treatment: Nissen Fundoplication

• Surgical procedure for severe GERD where the LES is tightened by wrapping the top of the stomach around the esophagus.

GERD: Potential Outcomes and Nutrition Considerations

• Inadequate nutritional intake due to appetite changes, abdominal pain, and food intolerances.
• Electrolyte imbalances secondary to vomiting.
• Iron deficiency from blood loss due to ulceration.
• Reduced iron, vitamin B-12, and calcium absorption associated with long-term use of acid-reducing medications.
• Difficulty swallowing.

GERD: Medical Nutrition Therapy (MNT)

• Avoidance of specific foods:
  • Peppermint or spearmint.
  • Chocolate.
  • Alcohol.
  • Caffeinated beverages.
  • High-fat foods (e.g., whole milk, cream, high-fat cheeses, fried foods, pastries).
  • Acidic foods (e.g., tomatoes).
  • Garlic, onions, black pepper, spicy foods.
  • Other foods that may cause individual intolerance.

GERD: Lifestyle Suggestions

• Weight loss for overweight or obese individuals.
• Avoid tight clothing.
• No smoking.
• Raise the head of the bed by 6-9 inches.
• Eat the last meal at least 3 hours before bedtime.
• Sit upright after eating and avoid lying down directly after meals.
• Limit the volume of food consumed at one time.
• Monitor for potential nutrient deficiencies due to long-term medication use.

Gastritis

• Inflammation of the stomach.
• Symptoms include nausea, vomiting, malaise, anorexia, hemorrhage, and pain.
• Can be acute or chronic:
  • Acute gastritis - rapid onset of inflammation.
  • Chronic gastritis - occurs over long periods, recurring symptoms.
• Causes include:
  • Viral, fungal, or bacterial infection.
  • Food poisoning.
  • Excessive/chronic alcohol ingestion.
  • Tobacco use.
  • Medications (NSAIDs - Aspirin, Naproxen, Ibuprofen).
  • Helicobacter pylori infection.
  • Most common causes are NSAIDs and H. pylori.

Gastritis

• Disruption of mucosal integrity can be caused by infections, chemicals or neural abnormalities.
• Gastritis can lead to atrophy, loss of parietal cells, loss of intrinsic factor and pernicious anemia, from decreased B12 absorption.
• Treatment includes antibiotics and acid-suppressing medications.

Gastritis: MNT

• Monitor tolerances and avoid poorly tolerated foods.
• Avoid highly seasoned or spicy foods.
• Small frequent meals may be helpful.
• Soft texture foods may be helpful.
• Chew foods thoroughly.
• Restricting fat intake may be helpful.
• Monitor for nutrient deficiencies:
  • B12, iron (non-heme), calcium (gastric acid needed for bioavailability)
  • Anemia (iron, B12, bleeding, acid-suppressing meds)

Duodenal and Gastric Ulcers

• The gastric and duodenal mucosa is protected from the digestive action of acid and pepsin by:
  • secretion of mucus
  • production of bicarbonate
  • removal of excess acid by normal blood flow
  • rapid renewal and repair of epithelial cell injury.
• Ulcers result from the breakdown of the normal defense and repair mechanisms.
• Ulcers typically exhibit chronic inflammation and repair processes.
• Four major complications:
  • Bleeding
  • Perforation
  • Penetration
  • Obstruction

Duodenal Ulcers

• Typically within the first few centimeters of the duodenal bulb.
• Characterized by increased acid secretion throughout the day, decreased bicarbonate.

Gastric/Peptic Ulcers

• Usually occur along the lesser curvature.
• Breakdown of the gastric mucosa; primary causes are Heliobacter pylori (>75% peptic ulcers), aspirin and other NSAIDs, corticosteroids, gastritis.

Stress Ulcers

• Can occur anywhere: fundus, antrum, duodenum, distal esophagus.
• Complication of metabolic stress (inflammation) caused by surgery, trauma (including burns), shock, renal failure, radiation therapy.
• Acute bleeding is a concern.

Duodenal and Gastric Ulcers: Medical Management

• Antibiotics (H pylori infection).
• Reduce or withdraw use of NSAIDs.
• Antacids.
• Histamine-2 antagonists, proton pump inhibitors.
• Avoid tobacco.

Duodenal and Gastric Ulcers: Nutritional Management

• Limit or avoid:
  • Alcohol.
  • Coffee, caffeine.
  • Spices (red and black pepper in particular, when inflamed).
  • Garlic.
• “Liberal bland” diet.
• Monitor for anemia.
• Treat complications accordingly.

Gastroparesis

• Delayed gastric emptying in the absence of mechanical obstruction.
• Also known as gastric stasis, diabetic gastropathy.
• Common symptoms include:
  • Early satiety.
  • Fullness.
  • Decreased appetite, anorexia.
  • Nausea and vomiting.
  • Abdominal bloating.
  • Halitosis, bad breath.
  • Upper abdominal pain.
• Diabetes, viral infection, or post-surgical complications are the most common causes, but >30% are idiopathic (without known cause).
• Intervention: Medical (motility agents)
  • metoclopramide (Reglan)
  • erythromycin

Gastroparesis: MNT

• Avoid large portions.
• Small frequent meals (4-6 per day).
• Avoid foods high in fat, may delay gastric emptying.
• Limit fiber intake, may delay gastric emptying.
• Chew foods thoroughly.
• Shifting food to pureed, or liquefied food can help:
  • Liquids empty in part by gravity, don't require antral contraction.
  • Liquids with fat better tolerated than solids with fat.
  • Don't restrict in patients struggling to meet needs.
• For enteral nutrition, would need to feed into small bowel (J-tube).

Inflammatory Bowel Disease

• Chronic inflammatory condition of the gastrointestinal tract.
• Ultimately damages the intestinal mucosa.
• Etiology unknown: thought to be an interaction of both environmental and clinical factors, causing a response in genetically predisposed individuals.
  • Smoking, infectious agents, intestinal flora, western diet, physiological changes in the small intestine triggering an abnormal inflammatory response.
• Two major forms: Crohn's and Ulcerative Colitis.
• Differ based on symptoms, gastrointestinal involvement, type of inflammation, biopsy, and antibody testing.
  • Crohn's can affect any portion of the GI tract, mouth to anus:
    • 50-60% of cases involve the distal ileum and colon.
    • ~75% involve the small intestine; involvement of the small intestine places individuals at higher nutritional risk than disease involving only the colon.
• Ulcerative Colitis involves the colon/rectum.
  • 40-50% have disease involving the rectum only.
  • Can be cured by removing the colon.
  • Always begins in the rectum and proceeds proximally.

Inflammatory Bowel Disease: Clinical Phenotypes

• Crohn's Disease: mouth to anus.
  • 5% gastroduodenal.
  • 5% small intestine alone.
  • 35% distal ileum.
  • 20% colon alone.
  • 35% right colon.
• Ulcerative Colitis: involves the colon/rectum.
  • 40-50% have disease involving the rectum only.
  • Can cure by removing the colon.
  • Always begins in the rectum and proceeds proximally.

Inflammatory Bowel Disease: Crohn's Disease vs. Ulcerative Colitis

• Crohn's Disease:
  • Can affect any portion of the GI tract (50-60% involve distal ileum & colon).
  • Rectum may not be involved.
  • Not continuous; often with skipped areas of GI tract; healthy segments.
  • Symptoms: abdominal pain, diarrhea, fever, extra-intestinal manifestations (oral apthous ulcers).
  • Transmural inflammation; affects all layers of bowel wall.
  • Submucosal thickening, narrowed segments of bowel; obstruction.
  • Strictures and fistulas more common.
  • Malabsorption; disease involving the small intestine has higher nutritional risk.
• Ulcerative Colitis:
  • Disease activity limited to the large intestine & rectum.
  • Rectum always involved.
  • Always continuous, proximally from rectum; no “skip lesions”.
  • Symptoms: bloody diarrhea, abdominal pain/cramping, fever.
  • Diffuse ulceration; deep ulcers.
  • Limited to mucosa, epithelial lining.
  • Strictures and fistulas are rare.

Inflammatory Bowel Disease: Nutritional Considerations

• Inadequate nutrient intake:
  • Decreased appetite.
  • Increased nutrient needs.
  • Desire to limit post prandial diarrhea.
  • Numerous food intolerances.
  • Abdominal pain.
  • Dietary restrictions (actual & self-taught).
• Peristalsis from food intake causes cramping pain.
• Severe diarrhea leading to malabsorption.
• Drug-nutrient interactions; medication side effects.
• Self-taught information obtained from the internet à many restrictions.

Common Nutrient Deficiencies Seen With Crohn's Disease

• Problem/Deficiency | Probable Cause
• --- | ---
• Energy/Protein | Insufficient intake, anorexia, fear of abdominal pain/diarrhea, ↑ protein needs, catabolism, healing from surgery.
• Fluid and electrolytes | Short bowel syndrome; high volume diarrhea.
• Iron | Blood loss; inadequate intake; malabsorption.
• Magnesium, Zinc | Intestinal losses; especially from SBS, high volume diarrhea.
• Calcium, Vitamin D | Long-term steroid use, ↓ intake of dairy foods due to lactose intolerance or lactose restricted diets.
• Vitamin B12 | Surgical resections: loss of intrinsic factor (stomach) or absorption (ileal resection).
• Folate | Medications used to treat IBD.
• Water soluble vitamins | Surgical resections; loss of terminal ileum.
• Fat soluble vitamins | Steatorrhea; fat malabsorption.

Inflammatory Bowel Disease: Medications

• Anti-diarrheal medications, (immodium, lomotil, bismuth subsalicylate).
• Immunosuppressives, (6-mercaptopurine, Imuran, cyclosporine).
• Biologics, anti-TNF, cytokine directed inflammatory activity; (Remicade).
• Steroids, anti-inflammatory (prednisone, prednisolone).
• Aminosalicylic acid, (5-ASA), anti-inflammatory (Sulfasalazine, Azulfadine).
• Antibiotics, (cipro, flagyl).

Inflammatory Bowel Disease: Surgical Interventions

• Required in ~50-70% of patients with Crohn's Disease.
• Total colectomy is the most common procedure for Ulcerative Colitis.

IBD: MNT

• High protein, high calorie, low fiber diet indicated during flare state.
• Avoid raw fruits & vegetables, nuts/seeds, whole grains.
• Protein: 1-1.5g/kg, 1.3-1.5g/kg during flare.
• Energy: 25-30kcal/kg (increase if with severe diarrhea, 30-35kcal/kg).
  • 30-35kcal/kg (BMI 15-19), 35-45kcal/kg (BMI 20-24.9).
  • 45-55kcal/kg (BMI 25-29.9), 55-65kcal/kg (BMI 30-34.9).
  • 65-100kcal/kg (BMI 35 >).