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Alterations of Digestive Function Part 1 Chapter 34 Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Clinical Manifestations of Gastrointestinal Dysfunction Anorexia A lack of a desire to eat despite physiologic stimuli that would normally produce hunger. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Clinical Manifestations of Gastrointestinal Dysfunction Vomiting (emesis) The forceful emptying of the stomach and intestinal contents through the mouth Stimuli that initiate vomiting reflex include: Severe pain Distention or chemical irritation of the stomach or duodenum Activation of the chemoreceptor trigger zone in the medulla. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Clinical Manifestations of Gastrointestinal Dysfunction Vomiting (cont.) Vomiting is usually preceded by nausea and retching. Retching - nonproductive vomiting; begins movement of gastric and duodenal contents up through the esophagus toward the mouth. Projectile vomiting - spontaneous vomiting that is not preceded by nausea or retching. Associated with direct stimulation of the vomiting center in the brain Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Clinical Manifestations of Gastrointestinal Dysfunction Constipation Constipation is defined as infrequent or difficult defecation. Causes - low fiber diet; dehydration; lack of exercise; drugs or disorders that impair intestinal motility or obstruct the intestinal lumen; hypothyroidism. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Clinical Manifestations of Gastrointestinal Dysfunction Diarrhea Increased frequency of bowl movements with increased volume, fluidity, and weight of feces. More than three stools per day is considered abnormal. Stool volume and consistency is determined by water content of the colon and the presence of unabsorbed food, unabsorbable material, and intestinal secretions. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Clinical Manifestations of Gastrointestinal Dysfunction Diarrhea (cont.) Large-volume diarrhea - caused by excessive amounts of water or secretions in the intestines. Small-volume diarrhea - results from excessive intestinal motility, usually from inflammation. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Clinical Manifestations of Gastrointestinal Dysfunction Diarrhea (cont.) Major mechanisms of diarrhea: Osmotic diarrhea - nonabsorbable substance draws excess water into the intestine and increases stool weight and volume. • Causes - inability to digest lactose due to lactase and pancreatic enzyme deficiency; excessive ingestion of synthetic, nonabsorbable sugars. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Clinical Manifestations of Gastrointestinal Dysfunction Diarrhea (cont.) Major mechanisms of diarrhea: Secretory diarrhea - excessive mucosal secretion of fluid and electrolytes. • Causes - bacterial enterotoxins, exotoxins, or neoplasms. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Clinical Manifestations of Gastrointestinal Dysfunction Diarrhea (cont.) Major mechanisms of diarrhea: Motility diarrhea - food is not mixed properly, digestion is impaired, and motility is increased. • Causes - resection of the small intestine, fistula formation between loops of intestine and excessive motility of the intestine caused by diabetic neuropathy. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. ACTIVITY Explain why factors that slow movement of feces through the colon cause constipation, whereas factors the speed up movement of feces through the colon cause diarrhea. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Clinical Manifestations of Gastrointestinal Dysfunction Abdominal Pain Abdominal pain is caused by stretching, inflammation, or ischemia. Originates in the organs themselves (visceral pain) or in the peritoneum (parietal pain). Visceral pain is often referred to the back. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Clinical Manifestations of Gastrointestinal Dysfunction Abdominal Pain (cont.) Parietal pain - localized and intense pain from irritation of the parietal peritoneum. Visceral pain - from the organs themselves; it is poorly localized with a radiating pattern. Referred pain - visceral pain felt at some distance from a diseased or affected organ; felt in skin or deeper tissues that share a sensory pathway with the affected organ. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Clinical Manifestations of Gastrointestinal Dysfunction Gastrointestinal Bleeding Upper gastrointestinal bleeding - from the esophagus, stomach, or duodenum. Causes - most commonly from bleeding varices in the esophagus; also peptic ulcers, or a MalloryWeiss tear at the esophageal gastric junction from severe retching. Hematemesis - bright red bleeding or dark “coffee ground” material (affected by stomach acids). Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Clinical Manifestations of Gastrointestinal Dysfunction Gastrointestinal Bleeding (cont.) Lower gastrointestinal bleeding - from the jejunum, ileum, colon, or rectum. Causes - polyps, inflammatory disease, cancer, or hemorrhoids. Melena - Black, sticky, tarry, foul-smelling stools caused by digestion of blood. Hematochezia - fresh, bright red blood passed from the rectum. Occult bleeding - traces of blood in normalappearing stools; detectable only with guaiac test. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Clinical Manifestations of Gastrointestinal Dysfunction Gastrointestinal Bleeding (cont.) Acute, severe gastrointestinal bleeding is life threatening, depending on volume and rate of loss. Chronic gastrointestinal bleeding can cause iron-deficiency anemia. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. GI Bleeding Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Disorders of Motility Dysphagia Dysphagia is difficulty swallowing. Results from mechanical obstruction of the esophagus or a disorder that impairs its motility. Mechanical obstructions - tumors, strictures, and diverticular herniations (outpouchings). Functional obstructions - neurological or muscular disorders that interfere with voluntary swallowing or peristalsis. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Disorders of Motility Dysphagia (cont.) Achalasia - form of functional dysphagia caused by denervation of smooth muscle in the esophagus; results in loss of esophageal peristalsis and failure of the lower esophageal sphincter (LES) to relax. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Achalasia Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Disorders of Motility Gastroesophageal Reflux Disease (GERD) GERD - reflux of chyme from the stomach to the esophagus. Reflux esophagitis - inflammation of the esophagus due to repeated exposure to acids and enzymes. Normally the lower esophageal sphincter (LES) prevents reflux of acidic chyme. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Gastroesophageal Reflux Disease Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Disorders of Motility Gastroesophageal Reflux Disease (cont.) Causes - loss of muscle tone in LES or increased abdominal pressures. Manifestations - heartburn, dysphagia, and upper abdominal pain within 1 hour of eating. Sequealae - GERD may cause esophageal ulcerations and strictures, and possibly cancer. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Disorders of Motility Hiatal Hernia Protrusion of the upper part of the stomach through the diaphragm at the gastroesophageal junction. Sliding hiatal hernia - stomach slides into the thoracic cavity through the esophageal hiatus. Paraesophageal hiatal hernia - greater curvature of the stomach herniates through a secondary opening in the diaphragm and lies alongside the esophagus. Strangulation of the hernia is a major complication. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Hiatal Hernia Sliding hiatal hernia Paraesophageal hiatal hernia Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Disorders of Motility Hiatal Hernia Manifestations - may be asymptomatic; but often exhibit gastroesophageal reflux, dysphagia, heartburn, and epigastric pain; regurgitation and substernal discomfort after eating. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Disorders of Motility Pyloric Obstruction Blocking or narrowing of the opening between the stomach and the duodenum. Causes - congenital defect, inflammation and scarring secondary to a gastric ulcer, or tumor growth. Manifestations - epigastric pain and fullness after eating, nausea, succussion splash, vomiting, and, with a prolonged obstruction, malnutrition, dehydration, and extreme debilitation. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Disorders of Motility Intestinal Obstruction and Ileus Intestinal obstruction - any condition that prevents the flow of chyme through the intestinal lumen or failure of normal intestinal motility in the absence of an obstructing lesion. Ileus - an obstruction of the intestines. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Disorders of Motility Intestinal Obstruction and Ileus Simple obstruction - mechanical blockage of the lumen, often by torsion, herniation, or a tumor. Functional obstruction - failure of motility (paralytic ileus), often occurring after abdominal surgery. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Intestinal Herniation Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Disorders of Motility Intestinal Obstruction and Ileus Intussusception - telescoping of a section of small intestine into the distal portion of the bowel. Volvulus (torsion)- twisted loop of intestine and mesentery. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Intussusception Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Volvulus (Torsion) Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Volvulus and Intussusception Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Disorders of Motility Intestinal Obstruction and Ileus Pathophysiology: Fluid and gas accumulate upstream of blockage, causing distension of the intestinal wall. Pressure from distension reduces blood flow, resulting in ischemic damage, which allows intestinal contents and bacteria to leak into peritoneum; fluids shift into peritoneal cavity. Blockage reduces absorption of fluids and electrolytes. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Disorders of Motility Intestinal Obstruction and Ileus Manifestations - colicky pain that occurs intermittently as a peristaltic wave of muscle contraction meets the obstruction; vomiting; and abdominal distension. Sequealae - fluid and electrolyte losses cause acidosis, hypokalemia, dehydration, hypovolemia, hypotension and shock; ischemia causes necrosis, perforation of intestinal wall and peritonitis. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Intestinal Obstruction Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Gastritis Acute or chronic inflammation of the gastric mucosa. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Gastritis Acute gastritis Inflammation that erodes the surface epithelium in a diffuse or localized pattern. Usually due to injury of the protective mucosal barrier caused by drugs or chemicals. NSAIDs cause gastritis by inhibiting prostaglandins, which stimulate secretion of mucus. Alcohol, histamine, digitalis, and metabolic disorders can contribute. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Gastritis Acute gastritis (cont.) Manifestations - vague abdominal discomfort, epigastric tenderness, and bleeding. Treatment - healing usually occurs spontaneously within a few days. Discontinuing injurious drugs, using antacids, or decreasing acid secretion with cimetidine (Tagamet®, a histamine H2receptor antagonist) facilitates healing. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Gastritis Chronic gastritis More complex and serious than acute gastritis. Characterized by atrophy of the gastric mucosa. Most commonly a result of chronic infection by H. pylori bacteria; also autoimmune conditions. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Gastritis Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. H. pylori Infection Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Gastritis 1. Chronic fundal gastritis (atrophic gastritis) Affects fundus and body. Most severe form. Can result in gastric atrophy and decreased secretion of hydrochloric acid, pepsinogen, and intrinsic factor, which can lead to pernicious anemia. This is a risk factor for developing gastric carcinoma. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Gastritis 2. Chronic antral gastritis Affects pyloric antrum Most common type Not usually associated with impaired secretion or gastric atrophy. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Gastritis Chronic gastritis Manifestations - symptoms often do not correlate with the severity Symptoms are often vague, including anorexia, fullness, nausea, vomiting, and epigastric pain Clinical signs include diminished secretion of hydrochloric acid (achlorhydria) and gastric bleeding. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Gastritis Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. ACTIVITY What treatments would be appropriate for treating chronic gastritis (including its sequelae)? Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Peptic Ulcer Disease Break or ulceration in the protective mucosal lining of the lower esophagus, stomach, or duodenum. Caused by excessive secretion of gastric acid, disruption of the protective mucosal barrier, or both. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Peptic Ulcer Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Peptic Ulcer Disease Risk factors - smoking, advanced age, habitual use of nonsteroidal anti-inflammatory drugs (NSAIDs), alcohol, psychological stress, and Helicobacter pylori infection, chronic diseases such as emphysema, rheumatoid arthritis, cirrhosis, and diabetes. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Peptic Ulcer Disease Duodenal ulcers Ulceration of the duodenal mucosa and submucosa layers. Most common of the peptic ulcers. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Duodenal Ulcer Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Peptic Ulcer Disease Duodenal ulcers Causes: Infection with H. pylori - releases toxins and enzymes that promote inflammation and ulceration. Nonsteroidal anti-inflammatory drugs (NSAIDs) inhibit mucosal prostaglandin synthesis. Hypersecretion of acid and pepsin by stomach due to high gastrin levels and smoking. Inadequate secretion of bicarbonate by the duodenal mucosa. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Peptic Ulcer Disease Duodenal ulcers Clinical manifestations - epigastric pain that begins 2 to 3 hours after eating, most often at night. Ingestion of food or antacids usually relieves pain. Complications - perforation of the duodenal wall with development of peritonitis. Treatment - avoidance of smoking, NSAIDs, and alcohol; antibiotics to treat the H. pylori infection; and proton pump inhibitors (PPIs) to prevent gastric acid production. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Peptic Ulcer Disease Gastric Ulcers Tend to develop in the antral region of stomach, adjacent to the acid-secreting mucosa of the body. Less common than duodenal ulcers. Causes are similar to those of duodenal ulcers, including chronic H. pylori infection and NSAID use. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Gastric Ulcers Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Peptic Ulcer Disease Gastric Ulcers Pathophysiology: The primary defect is reduced mucus secretion an increased mucosal permeability to H+ ions. Gastric secretion tends to be normal or less than normal. Clinical manifestations - epigastric pain immediately after eating, anorexia, vomiting, and weight loss. Treatment - same as for duodenal ulcers. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Gastric Ulcers Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Peptic Ulcer Disease Stress Ulcers Peptic ulcers that result from severe physiologic stress such as burns, head injury, multiple trauma, severe infection, and mechanical ventilation. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Stress Ulcers Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Peptic Ulcer Disease Stress Ulcers Types: 1. Ischemic ulcers - develop suddenly after severe illness, systemic trauma, or neural injury. Ulceration follows mucosal damage caused by decreased blood flow to the gastric mucosa. 2. Curling ulcers – ischemic ulcers that develop as a result of burn injury. 3. Cushing ulcers - caused by head trauma or brain surgery. Ulceration follows hypersecretion of gastric acid due to overstimulation of the vagal nuclei. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Peptic Ulcer Disease Stress Ulcers Clinical manifestations - often form multiple painless ulcers in the stomach and duodenum which present as occult bleeding in fecal tests. Life-threatening hemorrhage may be the first indication of their presence. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Peptic Ulcer Disease Ulcer surgery - peptic ulcers may be treated surgically if the patient suffers recurrent or uncontrolled bleeding or perforation of the stomach or duodenum. Gastrectomy - resection of all or part of the stomach. Anemia can result due to decreased production of intrinsic factor (which decreases B12 absorption). Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Malabsorption Syndromes Malabsorption syndromes result in impaired digestion or absorption of nutrients. Maldigestion - failure of the chemical processes of digestion. Malabsorption - failure of the intestinal mucosa to absorb digested nutrients. Maldigestion and malabsorption frequently occur together. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Malabsorption Syndromes Pancreatic Insufficiency Insufficient pancreatic enzyme production causes malabsorption associated with impaired digestion. The pancreas does not produce sufficient amounts of the enzymes that digest protein, carbohydrates, and fats into components that can be absorbed by the intestine. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Malabsorption Syndromes Pancreatic Insufficiency Causes - pancreatitis, pancreatic carcinoma, pancreatic resection, and cystic fibrosis. Clinical manifestations - fatty stools, diarrhea, weight loss, and failure to thrive. Treatment - oral replacement of pancreatic enzymes during meals. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Pancreatic Insufficiency Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Malabsorption Syndromes Lactase deficiency Deficient lactase production in the brush border of the small intestine results in lactose intolerance. Inhibits the breakdown of lactose (milk sugar) and prevents its absorption. Fermentation of lactose by bacteria causes gas (cramping, pain, flatulence, etc.). Excess lactose in lumen draws fluid in and increases gut motility, causing osmotic diarrhea. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Malabsorption Syndromes Lactase deficiency Causes - can be genetic (more common in certain ethnic groups) or caused by diseases of the intestine such as gluten-sensitive enteropathy. Generally does not develop until adulthood. Treatment - avoidance of lactose-containing foods. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Malabsorption Syndromes Bile Salt Deficiency Bile salts are needed to emulsify and absorb fats and fat-soluble vitamins. Synthesized from cholesterol in the liver. Bile salt deficiency causes fat malabsorption and steatorrhea (fatty stools). Causes - liver disease, obstruction of the bile duct, intestinal hypomotility, and Crohn disease. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Malabsorption Syndromes Bile Salt Deficiency Clinical manifestations: Poor intestinal absorption of lipids causes fatty stools and diarrhea. Malabsorption of fat-soluble vitamins causes vitamin deficiencies. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Malabsorption Syndromes Bile Salt Deficiency Clinical manifestations of vitamin deficiencies: Vitamin A - night blindness Vitamin D - decreased calcium absorption, bone pain, osteoporosis, fractures. Vitamin K - prolonged prothrombin time, purpura, and petechiae Vitamin E - uncertain; may cause testicular atrophy and neurologic defects in children. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Malabsorption Syndromes Bile Salt Deficiency Treatment - increase medium-chain triglycerides in the diet (coconut oil); oral bile salts; injections of Vitamins A, D, and K. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Inflammatory Bowel Diseases Chronic, relapsing inflammatory bowel disorders of unknown origin. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Ulcerative Colitis Chronic inflammatory disease that causes ulceration of the colonic mucosa, usually in the rectum and sigmoid colon. Possible causes - although the specific cause is unknown it is related to a number of factors: Genetics - runs in families and more common is certain ethnic groups (Caucasians, Jews). Autoimmunity - associated with other autoimmune diseases such as systemic lupus erythematosus (SLE); immune cells cause inflammation of mucosa. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Ulcerative Colitis Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Ulcerative Colitis Pathophysiology: Injury to the colon is mediated by macrophages, T cytotoxic cells, and the production of anticolon antibodies. These cause inflammatory ulceration in the large intestine with mucosal erythema and edema. Ulceration and swelling cause narrowing of the colonic lumen, diarrhea, and significant bleeding (hematochezia). Process begins in the rectum and advances up through the colon in a continuous manner and does not "skip" parts of the mucosa. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Ulcerative Colitis Clinical manifestations: Most often presents in early adulthood. Usually of sudden onset, with severe signs and symptoms. Frequent loose bowel movements (10 to 20 stools per day) with bloody stools. Crampy abdominal pain and dehydration. Bleeding can cause iron-deficiency anemia. A course of frequent remissions and exacerbations is common. Increased risk of infection, perforation, strictures, and colon cancer. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Ulcerative Colitis Treatment - anti-inflammatory drugs; colonic resection with colostomy placement may be necessary. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Crohn Disease http://www.youtube.com/watch?v=k0kRSF80 PJ0 4:21 min Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Crohn Disease Similar to ulcerative colitis, but it affects both the large and small intestines. Most often involves ascending and transverse colon and distal ileum; rarely involves rectum. Ulceration tends to involve all the layers of the intestinal wall (not just the mucosa). “Skip lesion” fissures (affected areas separated by normal ones) and granulomas are characteristic. Similar risk factors and theories of causation as ulcerative colitis. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Crohn Disease Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Crohn Disease Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Crohn Disease Clinical manifestations - symptoms vary considerably from person to person. Usually develops slowly. Diarrhea, abdominal pain, and weight loss are typical. Anemia due to deficiency of vitamin B12 and folic acid absorption. Weight loss due to inadequate absorption of nutrients. Fistulae formation. Bloody diarrhea is less common than in ulcerative colitis. Treatment - similar to ulcerative colitis. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Crohn vs. Ulcerative Colitis Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Diverticular Disease of the Colon Diverticula - outpouchings of colonic mucosa through the muscle layers of the colon wall. Most common in sigmoid colon. Diverticulosis - asymptomatic condition characterized by presence of diverticula. Associated with a diet low in fiber and high in refined foods, constipation, and increased pressure on weakened colon walls. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Diverticular Disease of the Colon Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Diverticular Disease of the Colon Diverticulitis - inflammation of the diverticula. Caused by a fecolith (impacted fecal matter) that blocks the opening of a diverticulum, causing irritation and bacterial growth. Clinical manifestations - lower left quadrant abdominal pain (since sigmoid colon is usually involved), fever, and episodes of diarrhea and/or constipation. Sequelae - bleeding, necrosis of wall, perforation, peritonitis, fistula formation, and stenosis of the colon causing obstruction. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Appendicitis Inflammation and infection of an outpouching of the vermiform appendix. Usually develops during early adulthood, although it can occur in children. Cause - obstruction of the appendix with fecal matter causes inflammation, infection, edema, and ischemia of the appendix. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Appendicitis Normal appendix Inflamed appendix Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Appendicitis Clinical manifestations: Initially pain is in epigastric or umbilical region, but swelling causes contact with the sensitive parietal peritoneum, causing pain to move to lower right quadrant. Anorexia (from pain), nausea and vomiting. Low grade fever. Leukocyte count moderately elevated. Treatment - surgical removal of the appendix and administration of antibiotics. Without surgical resection, inflammation may progress to gangrene, perforation, and peritonitis. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. ACTIVITY What are some similarities between appendicitis and diverticulitis? Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Irritable Bowel Syndrome IBS is a functional disorder with no known structural or biochemical alterations “Spastic colon” Involved in up to half of the GI problems for which people seek help. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Irritable Bowel Syndrome Symptoms vary, but can include cramping, fatigue, and constipation alternating with diarrhea. Diarrhea symptoms are due to increased intestinal motility, reducing the time for fluid absorption. Cramping is due to a loss of peristaltic coordination with conflicting waves of peristalsis. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Irritable Bowel Syndrome Factors involved: Alterations in the brain-gut axis with intestinal hypersensitivity Abnormal GI motility and secretion Intestinal infection Changes in composition of intestinal flora Food allergy or intolerance Psychosocial factors such as emotional stress Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published. Irritable Bowel Syndrome Treatment - no cure; treatments aim at easing the symptoms, including antidepressants, antispasmotics, visceral analgesics, antidiarrheals, laxatives, and fiber. Elsevier items and derived items © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Some material was previously published.