Digestive System Disorders - 2 Flashcards
Antiemetic
E.g. dramamine - reduces vomiting resulting from drugs, motion sickness, radiation
Antidiarrheal
E.g. imodium - reduces intestinal motility
Anti-inflammatory
Prednisone - Reduces inflammation. Prednisone blocks immune response
Acid-reduction
Zantac, PPIs - Reduces secretion of HCl in stomach
Antimicrobial
Biaxin - combination therapy for H. Pylori infection
Coating agent
Carafate - covers ulcer to allow healing
Antacid
Maalox - reduces hyperacidity
Laxative
Psyllium - With water, increases fecal bulk
Anticholinergics
Pirenzepine - reduces PNS activity - reduces secretion and mobility
Histamine-2 blockers
Zantac - inhibits acid production in stomach
PPI
Reduces gastric secretions
Aphthous ulcers - canker sores
Strep Sanguis - resident flora of oral cavity, often accompany fevers, stress, ingestion of certain foods. Small, shallow, painful lesions. Punched out, whitish appearance
Candidiasis
Often part of the normal resident flora of the mouth, opportunist under certain conditions. Oral candidiasis (thrush) - fungal infection that occurs in individuals who have received broad-spectrum antibiotics, cancer chemo, or glucocorticoids, or diabetes or immunosuppressed.. Whitish patches that can be wiped off to reveal erythema.
Syphilis
Oral lesions, contain microorganisms that are highly contagious during the first and second stages. Primary stage characterized by a chancre, a painless ulcer usually found on the tongue, lips, or palate. The lesion healths spontaneously in a week or two. Second stage - red macules or papules on the palate, or by mucous patches, multiple irregular, loose, white necrotic material on the mucosa which is highly infectious, red rash. Usually treated with penicillin because the organism can exist in general ciruclation.
Dental caries
Tooth decay, cavities. Invection involving Streptococcus mutans as the initiator, followed by increased numbers of Lactobacillus and other acid-producing resident flora in the oral cavity. The bacteria act on sugars and create large quantities of lactic acid that dissolve minerals in tooth enamel. Fluoride - decreases solubility of minerals in enamel and enhances remineralization.
Periodontal disease
Peridonteum consists of the gingivae (gums) and the anchoring structure for the teeth - the alveolar bone around the teeth, the cementum (outer covering of the root of the tooth) and the periodontal ligament joining the cementum to the bone. Periodontitis is the infection and damage to the periodontal ligament and bone by microorganisms, and the loosening of teeth.
Gingivitis
Inflammation of the gingiva, tissue becomes red, soft and swollen and bleeds easily. Can be caused by accumulated plaque (mass of bacteria and debris adhering to the tooth)
Tartar
Calcified plaque
Necrotizing periodontal disease (trench mouth)
Common infection caused by anaerobic opportunistic bacteria in individuals in whom tissue resistance is decreased by stress, smoking, disease, or nutritional deficits.
Periodontitis
More serious forms of periodontal disease - increase in activity of gram-negative anaerobic bacteria as they enter the plaque. These microbes secrete toxins and enzymes destructive to the tissues and white blood cells.
Hyperkeratosis
Leukoplakia - whitish plaque or epidermal thickening of the mucosa that occurs on the buccal mucosa, palate, lower lip or tongue. Can lead to squamous cell carcinoma.
Oral squamous cell carcinoma
Smokers, leukoplakia, alcohol abuse. Malignant tumors can be hidden and painless. Can spread to lymph nodes. Appears initially as whitish thickening
Sialadentitis
Salivary gland disorder. Inflammation of the salivary glands, Can be infectious or non infectious.
Infectious parotitis
Mumps, viral infection, bilateral swelling of the gland.
Dysphagia
Difficulty swallowing
Neurological deficit - infection, stroke, brain damage, achalasia - failure of lower esophageal sphincter to relax due to loss of innervation, loss of peristalsis in lower esophagus.
Muscular disorder
Mechanical obstruction
Stenosis
Narrowing of the esophagus, developmental or acquired. Can also result from scar tissue - formed after ingestion of corrosive chemicals.
Esophageal diverticula
Outpouchings of the esophageal wall resulting either from congenital defects or inflammation. Obstructs the flow of food down the esophagus, causes irritation, inflammation and scar tissue. Dysphagia, bad breath, chronic cough, hoarseness.
Hiatal Hernia
Part of stomach protrudes through hiatus in diaphragm into the thoracic cavity. Sliding - the hernia moves back to normal when standing. Paraesophageal - part of the fundus moves up through hiatus and blood vessels in the wall may be compressed leading to ulceration. Food can lodge causing inflammation, reflux, and dysphagia. Caused by shortened esophagus, weak diaphragm, increased abdominal pressure. Signs include heartburn, sour taste in mouth from reflux
Gastroesophageal Reflux Disease
Periodic flow of gastric contents into the esophagus, often seen in conjunction with hiatal hernia. Severity depends on competence of the lower esophageal sphincter or relative pressures on either side. Inflammation and ulceration of mucosa, can cause fibrosis and stricture in the esophagus. Eliminating factors - caffeine, fatty foods, alcohol, smoking, drugs, spicy foods.
Gastritis
Inflammation of the stomach, acute or chronic. Acute - Gastric mucosa is inflamed and appears red and edematous, may be ulcerated and bleeding. Caused by:
Infection by bacteria or virus, allergies, ingestion of spciy or irritating foods, excessive alcohol intake, ingestion of aspirin on an empty stomach, ingestion of corrosive or toxic substances, radiation or chemo.
Signs: anorexia, nausea, vomiting, hematemesis, epigastric pain, cramps, fever, headache, possible diarrhea.
Usually self-limiting and gastric mucosa regenerates.
Gastroenteritis
Involvement of the stomach and intestines in an inflammatory process, from infection or allergic reaction. Inflammation of gastric mucosa stimulates vomiting, diarrhea results when the inflammation of the intestines causes increased motility. Nausea and abdominal cramps, fever and malaise.
Usually self-limiting.
Escherichia coli
E. Coli - usually harmless microbe, normally resident in the intestine.
Some infective types can adhere to the mucosa and secrete an enterotoxin, causing gastroenteritis - travellers diarrhea.
Some strains are invasive and cause five forms of intestinal disease.
Onset is acute with severe, watery diarrhea and cramps, progressing to bloody diarrhea and lasting up to a week. In some people the toxin is absorbed and circulates to cause hemolysis of blood cells, can cause anemia and renal failure.
Chronic gastritis
Atrophy of the mucosa of the stomach, with loss of secretory glands. Lack of parietal cells causes achlorhydria and lack of secretion of intrinsic factor, required for absorption of B12. H. pylori often present.
Signs: anorexia, food intolerance, epigastric discomfort, , increased risk of peptic ulcers and gastric carcinoma.
Peptic Ulcer.
Found in duodenum and stomach and lower esophagus
Round cavities, penetrate submucosa. Acid penetrates muscle wall. May erode muscularis and penetrate the wall. Can hit a blood vessel and cause bleeding. Iron deficiency and occult blood
Many factors contribute to decreased resistance of mucosa -
H pylori
Inadequate blood supply (vasoconstriction caused by stress, smoking or shock, severe anemia)
Glucocorticoid secretion or medication - prednisone with catabolic effects
Substances that break down the mucus layer like aspirin, nonsteroidal anti-inflammatory drugs or alcohol
Atrophy of gastric mucosa (chronic gastritis)
Increased acid-pepsin secretions associated with:
Increased gastrin secretion
Increased vagal stimulation or hyper sensitivity to stimuli
Increased number of acid-pepsin secretory cells in stomach
Increased stimulation of acid-pepsin secretion by alcohol, caffeine, or certain foods
Interference with the normal feedback mechanism that reduces acid-pepsin secretion when the stomach is empty
Rapid gastric emptying
What happens when an ulcer erodes completely through the wall?
Chyme enters the peritoneal cavity, resulting in chemical peritonitis, inflammation of the peritoneal membranes and other structures of the abdominal cavity. Inflammation can cause increased permeability of the intestinal wall, passage of bacteria and their toxins into the peritoneal cavity and bacterial peritonitis.
What can recurrent ulceration cause?
Obstruction of digestive tract can result from stricture from scar tissue.
Symptoms of ulcer
Epigastric burning or aching, usually 2 to 3 hours after meals and at night. Heartburn, nausea, vomiting, weight loss. Food intake can relieve discomfort between meals.
Anemia, and occult blood.
Treatment for ulcer
Two or three antimicrobial drugs and medication to reduce acid secretion. Coating agents, antacids. Reducing exacerbating factors. Surgery.
Stress ulcer
Result from severe trauma, such as burns or head injury, occur with serious systemic problems such as hemorrhage or sepsis. Form within hours of precipitating event as the blood flow to the mucosa is greatly reduced, leading to reduced secretion of mucus and epithelia regeneration. Mucosal barrier is lost, acid diffused into the mucosa.
Gastric Cancer
Arises primarily in the mucous glands, most occur in the antrum or pyloric area. Early involves mucosa and submucosa, advanced involves the muscularis layer. Can extend to serosa and to lymph nodes.
Signs are usually milk until advanced. Anorexia, indigestion, epigastric discomfort, weight loss, fatigue, feeling of fullness. Occult blood, anemia.
Dumping Syndrome
Control of gastric emptying is lost, may occur after gastric resection (partial gastrectomy) - large quantities of of food are rapidly dumped into the intestine
Storage stage, dilution of chyme by gastric secretions is missed. Osmotic chyme draws more fluid into intestine, increases distention and motility. During or shortly after meals, cramps, nausea, diarrhea, hypovolemia can cause dizziness, weakness, rapid pulse, sweating.
Hypoglycemia - rapid gastric emptying and absorption leads to high blood glucose levelsand increased insulin secretion, which results in rapid drop in blood glucose with no reserve nutrients from the stomach - tremors, sweating, weakness.
Pyloric stenosis
Narrowing / obstruction of the pyloric sphincter, presence of fibrous scar tissue. In infants, vomiting, small infrequent stool, failure to thrive, dehydration, persistent hunger.
Adults - interference with gastric emptying - persistent feeling of fullness and increased vomiting.
Cholelithiasis
Refers to formation of gallstones, which are masses of solid material that form in the bile
Cholecystitis
Inflammation of gallbladder and cystic duct
Cholangitis
Inflammation usually related to infection of bile ducts
Choledocholithiasis
Obstruction by gallstones of biliary tract
Composition of gallstone
Cholesterol, bile pigment (bilirubin), calcium salts
How do gallstones form?
When bile contains a high concentration of a component such as cholesterol or there is a deficit of bile salts, inflammation of biliary structures.
Gallstones can cause irritation and inflammation in the gallbladder wall (cholecystitis) and the susceptible tissue may then be infected.
Biliary colic
Severe spasms of pain resulting from strong muscle contractions attempting to move gallstone along. Upper right quadrant of the abdomen, often radiates to back and right shoulder. Nausea and vomiting.
High risk for gallstones
Obesity
High cholesterol
Multiparity
Oral contraceptives
Jaundice
Hyperbilirubinemia. Yellowish color of skin and other tissues resulting from high levels of bilirubin in blood. Usually first apparent in the sclera. Product of breakdown of hemoglobin. Not a disease by a sign of many different types of disorders.
Prehepatic jaundice - results from excessive destruction of red blood cells, characteristic of hemoytic anemias or transfusion reactions.
Physiologic jaundice of the newborn - increased hemolysis of red blood cells combine with immature infant liver
Intrahepatic jaundice - occurs in people with liver disease, such as hepatitis or cirrhosis. Impaired uptake of bilirubin from the blood and decreased conjugation of bilirubin by the hepatocytes.
Posthepatic jaundice - obstruction of bile flow into gallbladder or duodenum and backup of bile into blood.
Hepatitis
Inflammation of liver. Can be idiopathic (fatty liver) or from a local infection (viral hepatitis) or from infection elsewhere in the body (mononuceosis) or from chemical or drug toxicity.
Mild inflammation -impairs hepatocyte function
Severe inflammation and necrosis - obstruction of blood and bile flow in the liver and impaired liver function and
Hepatitis
Infection from a group of viruses that specifically target the hepatocytes. Hep A, Hep B, Hep C, Hep D and Hep E.
Liver cells are damaged by direct action of virus (Hep C) or cell-mediated immune responses (Hep B)
Cell injury results in inflammation and necrosis in the liver. Necrosis may be present. Biliary stasis and backup of bile into blood may happen.
Hepatic cells may regenerate, or fibrous scar tissue may form that obstructs the channels used for blood and bile, further damage from ischemia.
How is Hepatitis spread?
Hep B, C, and D may exist in a carrier state, asymptomatic people can carry the virus in their hepatocytes and transmit infection via blood or body fluids. Hep A - Oral-fecal Hep B - blood and body fluids Hep C - blood and body fluids Hep D - blood and body fluids Hep E - oral-fecal Toxic hep - Direct exposure