Chapter 9 pathophysiology

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hiatal hernia

A hernia is the protrusion of part of an organ through a muscular wall or body opening. A ___________________ is the protrusion of part of the stomach through the diaphragm at the point where the esophagus joins the stomach. The condition is caused by either a congenital defect in the diaphragm or by increased intra-abdominal pressure associated with obesity. Figure 9-6 shows this condition. Indigestion and heartburn may occur after eating; shortness of breath may also occur. Diagnosis is based on a chest x-ray or EGD. The aim of treatment is to reduce symptoms. The most effective treatment is cholinergic drugs, which strengthen the cardiac sphincter and reduce reflux after eating. Patients should avoid irritants such as spicy foods and caffeine, take frequent small meals, and, if obese, lose weight. Surgery may be required to correct the structural defect, but ___________________s tend to recur following surgery. These hernias cannot be prevented.

gastritis

Acute ______________ is an inflammation of the lining of the stomach frequently accompanied by vomiting of blood. Acute ___________________is caused by irritants such as aspirin, excessive coffee, tobacco, alcohol, or infection. Acute alcoholism is a major cause of hemorrhagic gastritis. Chronic alcohol use stimulates acid secretion, which irritates the mucosa. EGD with biopsy (examination of a tissue sample) is extremely valuable in diagnosing this disease. A camera may be attached to the gastroscope to photograph the entire inner lining of the stomach. Treatment includes avoiding known irritants and treating infections. Treatment includes medicines that block gastric secretion. If bleeding occurs, surgery may be required

pancreatitis

Acute _______________ is a serious, painful inflammation of the pancreas. _______________is more prevalent in women than in men and usually occurs after age 40. In men it is often associated with alcoholism or peptic ulcers. In women it is more commonly associated with gallbladder disease. The prognosis is good if _______________is associated with gallbladder disease but is very poor if it is related to alcoholism. _______________may be caused by local swelling, necrosis, hemorrhage, or trauma. Severe, steady abdominal pain of sudden onset is the first symptom. The intense pain radiates to the back and resembles the sharp pain of a perforated ulcer. Drawing up the knees or assuming a sitting position may provide some relief. There may also be nausea and vomiting. Jaundice sometimes develops if the swelling blocks the common bile duct. If a large area of the pancreas is affected, both endocrine and digestive functions of the gland become impaired. In the absence of lipid enzymes from the pancreas, fat cannot be digested, resulting in greasy stools with a foul odor. Secondary malabsorption syndrome develops because fat that is not digested cannot be absorbed. In _______________, the protein- and lipid-digesting enzymes become activated within the pancreas and begin to digest the organ itself. Severe necrosis and edema of the pancreas result. The digestion can extend into blood vessels, which causes severe internal bleeding and shock. When the condition becomes this severe, it is called acute hemorrhagic _______________. The most significant diagnostic procedures for _______________are blood and urine tests for elevated pancreatic enzymes such as lipase and amylase. Stool may be tested for levels of fat, and an abdominal CT or ultrasound may be used to visualize the extent of inflammation. Treatment requires hospitalization, a few days of fasting, intravenous fluids, and analgesics. The underlying cause of the _______________may require treatment. To reduce the risk of _______________, one should stop smoking, stop drinking alcohol, and ensure good hydration.

age related diseases

Age-Related Diseases Infants and young children are especially vulnerable to the effects of digestive system disorders and diseases because their growing and developing bodies require substantial fluids, calories, and nutrients. For example, unchecked vomiting and diarrhea can cause dehydration and malnutrition more easily in children than in adults. The digestive system functions fairly well in healthy older adults, despite normal age-related changes such as thinning mucosa and decreased muscle motility. However, some diseases such as cancer occur with greater frequency with increasing age and thus significantly impact older populations. Mouth and Esophagus Dental caries (cavities) are more prevalent in children than in adults. After adolescence, the incidence of caries reduces and the risk for gingivitis and periodontal disease increases. Periodontal disease and osteoporosis contribute to tooth loss in older adults. The number of taste buds decreases, and together with decreased saliva secretion, this may lead to decreased appetite. Esophageal cancer incidence is highest in those over age 60. As stated earlier, this cancer is closely linked with the use of alcohol and tobacco. Gastrointestinal Tract Infectious diarrheal diseases are the leading cause of death in children worldwide. Children cannot tolerate the loss of enormous amounts of water, electrolytes, and nutrients associated with diarrhea. Hiatal hernia is a common disorder in older adults. Peptic ulcers are no more common in older than in middle-age people; however, the risk of hemorrhage is greater in old age. Colon cancer incidence increases after age 45, which emphasizes the importance of regular screening and early diagnosis. Diverticula are most common in older adults, and therefore the incidence of diverticulitis rises. Diarrhea poses a great risk of dehydration and malnutrition. Therefore, gastrointestinal infections such as food poisoning and dysentery can be serious diseases. Overall, the function of the intestines remains fairly normal, although intestinal motility is slightly decreased. Thus, changes in diet or new medications that affect intestinal motility can more easily lead to constipation or diarrhea. Liver and Gallbladder Liver and gallbladder disorders are uncommon in children. In adulthood, liver function diminishes with increasing age, which results in the persistence of high blood levels of medications or toxins. In old age, levels of clotting factors decline, increasing the risk for hemorrhage. The incidence of cholelithiasis is highest in those over age 80. Pancreas Pancreatic disorders in children are uncommon, although insulin-dependent (Type 1, or juvenile-onset) diabetes does begin in childhood. Type 2, formerly called adult-onset diabetes, is now increasingly occurring in children (as well as in adults) as a result of obesity. The incidence of pancreatic cancer peaks in the 60s and is most common among older men. Acute pancreatitis is common in older adults. In younger people, acute pancreatitis is associated with alcoholism, while in older adults acute pancreatitis is more likely due to gallstones that block the pancreatic duct.

intestinal obstruction

An obstruction can occur anywhere along the intestinal tract, preventing contents within the tract from moving forward. Obstructions are classed as organic when there is some material blockage. Other obstructions are classified as paralytic or functional when there is a decrease in peristalsis, preventing the propulsion of intestinal contents. Obstructions take several forms: • Tumors: physically obstruct intestine • Hiatal and inguinal hernias: intestine pinches as it protrudes through muscle of body wall • Volvulus: intestine twists on itself (Figure 9-10 ) • Adhesions: linking of two surfaces by fibrous scars; occurs following surgery or inflammation • Intussusception: a segment of intestine telescopes into the part forward to it

cancer of the pancreas (adenocarcinoma)

Cancer of the pancreas, ____________, has a high mortality rate. It occurs more frequently in males than in females and is most prevalent in men between the ages of 35 and 70. Pancreatic cancer is linked to cigarette smoking, high-protein and -fat diets, food additives, and exposure to industrial chemicals such as beta-naphthalene, benzidine, and urea. Chronic alcohol abuse, chronic pancreatitis, and diabetes mellitus increase the risk of developing pancreatic cancer. A malignancy in the head of the pancreas can block the common bile duct (Figure 9-13 ), and symptoms are experienced earlier than those of cancer in the body or tail of the pancreas, which can be very advanced before it is discovered. Obstruction of the bile duct causes jaundice and impairs digestion because the pancreatic enzymes and bile cannot enter the duodenum. This causes malabsorption of fat and clay-colored stools; sufficient nutrients and calories cannot be absorbed, and weight loss occurs. Great pain is experienced as the tumor grows, and the cancer usually metastasizes to the surrounding organs: the duodenum, stomach, and liver. Diagnosis depends on laparoscopic biopsy and ultrasound. Prognosis for cancer of the pancreas is poor, and death occurs in a relatively short time. Treatment, which is rarely successful, includes surgery, chemotherapy, and radiation. Pancreatic cancer cannot be prevented.

diagnostic test and procedures

Diagnosis of digestive system diseases and disorders relies on many types of laboratory tests, culturing, biopsy, imaging techniques, and other procedures. These are discussed with each of the diseases and disorders in this chapter. Infectious diseases in the digestive organs can be identified by culture and immunodiagnostic methods. For example, stool culture permits identification of pathogens in the feces. Many abnormalities and infections can be diagnosed using blood tests. For example, blood tests for liver enzymes are used to detect liver abnormalities and liver infections. Biopsy is used to identify several diseases. For example, colon cancer can be identified through biopsy. Malabsorption syndrome can also be identified through biopsy of the intestine's lining. Several digestive system diseases and disorders are diagnosed with CT, x-ray, ultrasound, and MRI. Several types of endoscopy allow visualization of abnormalities in the esophagus, stomach, small intestine, and large intestine. These imaging techniques and endoscopy have many applications and will be discussed throughout this chapter.

the gastrointestinal system

Digestion begins in the mouth with the mechanical breakdown of food. The secretion of saliva moistens the food and provides an enzyme for initial digestion of starch. The food is then swallowed and passes through the pharynx, or throat, and into the esophagus. The moistened food moves down the esophagus to the stomach. A sphincter muscle at the juncture of the esophagus and stomach prevents regurgitation while digestion continues. The stomach secretes gastric juice that contains enzymes, biological catalysts that act on protein. Gastric juice also contains hydrochloric acid, which activates these enzymes. The acidic gastric contents would be irritating to the stomach lining if the lining were not protected by a thick covering of mucus. A great deal of moistening and mixing occurs within the stomach. The moistened, mixed, and acidic food is called chyme. Chyme passes from the stomach into the small intestine through a sphincter muscle, the pyloric sphincter. This sphincter is closed until it receives nerve and hormonal signals to relax and open. Chyme is propelled along its course by rhythmic, smooth muscle contractions of the intestinal wall called peristalsis. Most digestion occurs in the first part of the small intestine, the duodenum. Intestinal secretions contain mucus and digestive enzymes, which enter by means of the pancreatic duct from the pancreas (Figure 9-2). The pancreas is a gland with both endocrine and exocrine functions. The endocrine portion secretes insulin and glucagon. The exocrine portion secretes enzymes that digest protein, lipid, and carbohydrate (Figure 9-3 ). The exocrine pancreas also secretes an alkaline solution for the neutralization of acid carried into the small intestine from the stomach. Bile, secreted by the liver and stored in the gallbladder, enters the duodenum through the common bile duct (Figure 9-4 ). Bile is an emulsifier, a substance that reduces large fat droplets into much smaller fat droplets, enabling the lipid enzymes to digest fat into small, absorbable units. When digestion is complete, nutrients such as sugars and amino acids are absorbed into blood capillaries and lymph vessels in the intestinal wall. The inner surface of the small intestine is arranged to provide the greatest amount of surface area possible for digestion and absorption. This mucosal surface contains numerous fingerlike projections called villi, each of which contains capillaries and lymph vessels for absorption (Figure 9-5 ). Material not digested passes into the large intestine, or colon. The first part of the colon is the cecum, to which the appendix, a fingerlike mass of lymphatic tissue, is attached. Water and minerals are absorbed from the large intestine, and the remaining matter is excreted as feces. In this chapter, the diseases of each part of the digestive system are described. These include diseases of the mouth, esophagus, stomach, small and large intestines, pancreas, liver, and gallbladder.

volvulus

Figure 9-11 shows various types of organic obstructions. An acute organic obstruction causes severe pain. The abdomen becomes distended and vomiting occurs. There is complete constipation; not even gas, or flatus, is passed. Sometimes the obstruction can be relieved by means of a suction tube, but frequently surgery is required. If the obstruction is a strangulated hernia, a protrusion of intestine through the abdominal wall, surgery is required because the strangulated segment can become gangrenous. A paralytic obstruction can result from peritonitis. If a loop of small intestine is surrounded by pus from the infection, the smooth muscle of the intestinal wall cannot contract. Sphincters can go into spasm and fail to open as a result of intense pain. These obstructions cannot be prevented.

viral hepatitis

Hepatitis, or inflammation of the liver, is caused by a number of factors, including several viruses. Important causes are hepatitis virus A, hepatitis virus B, hepatitis virus C, and hepatitis virus D. Hepatitis E is uncommon in the United States. Hepatitis virus A, formerly called infectious hepatitis, is the least serious form and can develop as an isolated case or in an epidemic. In the United States, as many as 30,000 people per year had hepatitis A infection until the hepatitus A vaccine was introduced between 1996 and 1999. Since introduction of the vaccine, the number of cases has dropped dramatically. The incubation period for hepatitus A, the time from exposure to the development of symptoms, is from 2 to 6 weeks. The symptoms include anorexia, nausea, and mild fever. The urine becomes dark in color, and jaundice appears in some cases. On examination, the liver may be found to be enlarged and tender. Contaminated water or food is the usual source of the infection, which spreads under conditions of poor sanitation. The virus is excreted in the stools and urine, infecting soil and water. Hepatitis virus A is usually mild in children; it is sometimes more severe in adults. Prognosis is usually good, with no permanent liver damage resulting. Immunoglobulin injections provide temporary protection against hepatitis virus A for people exposed to it. The vaccine now in use has proven to be effective. Exposure to hepatitis A gives lifetime immunity. Hepatitis virus B, formerly called serum hepatitis, is a more serious and common disease, affecting more than 60,000 Americans per year. In fact, 1.25 million Americans are chronically infected with hepatitis B, 25% of whom will die from cirrhosis. The symptoms are similar to those of hepatitis virus A, but develop more slowly. The incubation period is long, lasting from 2 to 6 months. The severity of the disease varies greatly. Those with poor nutritional status, for example, will be more adversely affected. Occasionally, a fulminating form of hepatitis virus B develops, and it is fatal. This form has a sudden onset and progresses rapidly. Delirium is followed by coma and death. Hepatitis virus B can be transmitted by donated blood or serum transfusions that contain the virus. It is also transmitted sexually and through contaminated needles or syringes used by drug addicts. Physical condition at the onset of the disease makes a difference in the seriousness of the infection. Blood and plasma are screened for hepatitis, but hospital personnel still must be well informed of the hazards that can lead to acquiring hepatitis. Precautions must be taken by nurses, laboratory technicians, dialysis workers, and blood bank personnel to prevent becoming infected. The hepatitis B vaccine provides immunity, and it should be administered to personnel who handle or come in close contact with blood or other bodily fluids. Hepatitis C infections have declined in the United States to approximately 26,000 per year, but hepatitis C remains the leading viral cause of chronic liver disease and cirrhosis and is now the most common reason for liver transplants. Because of the very high rates of infection seen in the 1980s, over 4 million Americans are infected today, 3.2 million of whom are chronically infected. The initial symptoms are nonspecific and similar to those of hepatitis A or B, but the disease persists for months, even years. About 20% of those infected with hepatitis C develop cirrhosis, and a number of these cases can lead to end-stage liver disease. The virus is transmitted mostly through blood transfusions, although transmission has been traced to intravenous drug use, and epidemiologic studies show a risk associated with sexual contact with someone with hepatitis and with having had more than one sex partner in a year. Treatments include interferon injections and oral ribavirin. Treatment for end-stage cirrhosis may include liver transplant. Hepatitis D virus is described as a defective virus because it cannot reproduce in a cell unless the cell is also infected with hepatitis B. The resulting disease is more serious and more frequently progresses to chronic liver disease. Rates of hepatitis D are not known because surveillance is not systematically conducted; however, hepatitis D is quite uncommon, although its transmission is known to be similar to that of hepatitis B. Hepatitis E is very rare in the United States, but worldwide it is the leading cause of epidemics of infectious hepatitis. Major epidemics occur in Africa, Asia, and Mexico, where it is transmitted primarily through fecal-contaminated drinking water. Nearly every case in the United States occurs in travelers to areas where the disease is endemic. No effective treatment or vaccine exists. Fortunately, there is no evidence that hepatitis E progresses to chronic disease.

Diseases of the liver

Liver disease manifests itself during inflammation or when chronic damage to liver cells cannot be repaired. When fibrous tissue replaces liver cells, the normal functions of the liver become impaired.

Diseases indicated by stool characteristics

Microscopic examination of stool may identify the cause of food poisoning, gastroenteritis, or dysentery. Other information can also be obtained from stool samples. Signs of several of the diseases discussed include blood in the stools. Blood appears differently, however, depending on the site of bleeding. If the blood in the stools is bright red, the bleeding originated from the distal end of the colon, the rectum. Streaks of red blood can indicate bleeding hemorrhoids. This symptom can also indicate cancer of the rectum. Dark blood may appear in the stools, giving them a dark, tarry appearance, known as melena. This blood was altered as it passed through the digestive tract, so it originated from the stomach or duodenum. A bleeding ulcer or cancer of the stomach may be indicated by melena. Certain medications (those containing iron, for instance) can also give this tarry appearance to the stools. Blood may not be apparent to the naked eye, but a chemical test can show its presence. This is referred to as occult blood. It can indicate bleeding ulcers or a malignancy in the digestive tract. If the stools are large and pale, appear greasy, and float on water, they contain fat. This is a symptom of malabsorption syndrome. It may also indicate a diseased liver, gallbladder, or pancreas. Diseases of these organs are discussed next.

Peptic Ulcer disease

Peptic ulcers have three main causes: infection with Helicobacter pylori, use of nonsteroidal antiinflammatory drugs, and an inherited disorder of excessive acid secretion. Because hydrochloric acid secretion is under nerve and hormonal control, stressful situations can trigger or exacerbate ulcers. Gastric contents contribute to ulcer formation in all cases. The ulcers are caused, in part, by pepsin, a proteolytic enzyme secreted by the stomach. Hydrochloric acid of the stomach, intestinal juice, and bile also irritate the gastric mucosa. Irritated and inflamed mucous membrane may become necrotic, leaving a hole. Heartburn and indigestion are frequently the first signs of an ulcer. The ulcer pain is caused by the action of hydrochloric acid on the exposed surface of the lesion. The muscular contractions of peristalsis also intensify the pain. Symptoms of gastric ulcer include nausea, vomiting, abdominal pain, and, occasionally, massive gastrointestinal bleeding. A potential complication of an ulcer is hemorrhage; severe hemorrhage may lead to shock. It is possible for a large artery at the base of the ulcer to rupture as the lesion erodes deeper into underlying tissues. Bleeding from the ulcer may appear as hematemesis or bloody vomitus, or the blood may appear in stools, where it gives the stools a dark, tarry appearance, referred to as melena. A serious ulcer complication is perforation. If an ulcer perforates—that is, breaks through the intestinal or gastric wall—there is sudden and intense abdominal pain. Peritonitis, inflammation of the lining of the abdominal cavity, usually results when the digestive contents enter the cavity, because this material contains numerous bacteria. Surgical repair of the perforation is required immediately. Obstruction of the gastrointestinal tract can result from an ulcer and the scar tissue surrounding it. Obstruction occurs most frequently in a narrow area of the stomach near the pyloric sphincter. Ulcer pain can cause the sphincter to go into spasm, also resulting in obstruction. Diagnosis is based on tests for H. pylori, endoscopy, an x-ray, detection of blood in stools, blood tests to determine elevated levels of white blood cells, and gastric content analysis. The main objectives of treatment for _______are to promote healing, prevent complications and recurrences, and provide pain relief. Acid reducers are more effective for peptic ulcers than are antacids and mucosal barriers. However, antibiotic therapy in combination with acid reducers is required to eradicate H. pyloriand to reduce the rate of ulcer relapse. If the ulcer is stress or tension related, certain changes in lifestyle or approach to stress might be beneficial to prevent the development of symptoms.

Gastroesophageal reflux disease (GERD)

The condition is known as __________________________ (___________________). ___________________ may be caused by an incompetent cardiac sphincter, which normally prevents stomach contents from ascending the esophagus. Other causes include hiatal hernia and medications that compromise the sphincter or induce excess acid secretion. The incidence of ___________________ increases with age, which suggests that age-related changes occur in the sphincter. Whatever the cause, regurgitated stomach acid irritates the lining of the esophagus and stimulates an inflammatory response. Diagnosis is based on history, signs, and symptoms as well as barium fluoroscopy, measure of esophageal pH, or EGD. Treatment includes a nonirritating diet, antacids, and acid-reducing medications. Painful symptoms frequently occur at night while the body rests horizontal and relaxed; thus patients are advised to sleep with the head elevated and to avoid eating 2-3 hours before sleeping. Prevention of symptoms requires taking frequent, small meals and avoiding alcohol.

anatomy and physiology review.

The digestive system consists of a digestive tract and accessory organs that assist the digestive process. The digestive tract begins at the mouth and includes the pharynx, esophagus, stomach, small intestine, and large intestine. The accessory organs include the liver, gallbladder, and pancreas (Figure 9-1 ).

malabsorption syndrome

The inability to absorb fat or some other substance from the small intestine is known as _______. The prevalence of _______ is not known because it is a syndrome that accompanies several other types of diseases and disorders. For example, a diseased pancreas or blocked pancreatic duct deprives the small intestine of lipase. In the absence of lipase, fat is not digested and cannot be absorbed. Also, liver disease or a blocked bile duct leads to inadequate bile secretion, which prevents lipid digestion and causes malabsorption. Signs and symptoms of malnutrition occur, including lack of energy and inability to maintain weight. Because fat cannot be absorbed from the intestine, it passes into the feces, and the result is unformed, fatty, pale stools with a foul odor. The fat content causes the stools to float. One of the complications of _______ is bleeding. Vitamin K, a fat-soluble vitamin that is essential to the blood-clotting mechanism, cannot be absorbed. Treatment for _______ depends on its cause, and diet is carefully controlled. Supplements are administered, such as the fat-soluble vitamins A, D, E, and K.

esophageal varices

Varicose (enlarged) veins that develop in the esophagus are called ___________________. The prevalence is unknown, but it affects mainly those who abuse alcohol and those with cirrhosis of the liver. Cirrhosis of the liver is the chief cause of ___________________. The destruction and scarring of tissue associated with cirrhosis impairs blood flow through the liver, which elevates pressure in the veins of the abdomen and elsewhere, including the esophagus. The increased venous pressure causes the esophageal veins to dilate and become knotty. The most serious danger in ___________________ is hemorrhage. Bleeding ___________________ require emergency treatment. Diagnosis requires endoscopy, specifically esophago-gastro-duodenoscopy (EGD), in which an endoscope, a tube with a camera, is inserted to look at the esophagus, stomach, and duodenum. Medical and surgical treatment attempts to reduce bleeding from the varices, but the prognosis is poor for bleeding varices. ___________________ cannot be prevented, but risk factors such as alcohol use and smoking can be avoided.

regional enteritis (Crohn's Disease)

_______ (_______) is an inflammatory disease of the intestine that most frequently affects the upper colon and sometimes the distal end of the ileum. _______ usually affects white adults ages 20-40, and is two to three times more common among Ashkenazi Jews. Risk factors are unknown but may involve family history or autoimmune disease. Possible causes include allergies, immune disorders, or stress, but the exact cause remains unknown. Signs and symptoms are related to the inflammation. As inflammation progresses, the intestinal walls become thick and rigid. With thickening, the lumen narrows and develops a chronic obstruction. The pain of _______ resembles that of appendicitis, occurring in the lower right quadrant of the abdomen, where a tender mass may be felt. Diarrhea, constipation, and melena are common. Severe diarrhea can cause an electrolyte imbalance because of the large amount of water and salt lost in the stools. Anorexia, nausea, and vomiting lead to weight loss. Periods of exacerbation, remission, and relapse are common; during flare-ups, the inflammation can also manifest as rheumatoid arthritis. Severe cases entail a risk for hemorrhage or perforation. _______ is diagnosed by CT and endoscopy, an elevated level of white blood cells, and low levels of potassium, calcium, and magnesium. Biopsy confirms the diagnosis. _______ is usually treated with anti-inflammatory medications and with immunosuppressive agents. Surgery is performed to correct complications such as obstruction, perforation, or massive hemorrhage. Ileostomy is necessary if the large intestine has been severely damaged. _______ cannot be prevented, but outbreaks can be controlled.

Ulcers

_______ are lesions of any body surface where necrotic (dead) tissue forms as a result of inflammation and is sloughed off, leaving a hole. _______ of the stomach and small intestine are termed peptic _______. Types of peptic _______ are _______ of the stomach, called gastric _______, and those of the small intestine are duodenal _______. Approximately 80% of peptic _______ are duodenal

cancer of the stomach

_______ is a malignant tumor originating from stomach tissues. The incidence of stomach cancer in the United States has dropped dramatically over the past 30 years. It has become an uncommon disease and accounts for less than 1% of all cancers. Stomach cancer is the ninth leading cause of cancer death in men, and is more prevalent among men over age 40 than among women. H. pylori infection appears to increase the risk for stomach cancer, probably through its damaging effects on the mucosal cells. The stomach cancer may be a large mass projecting into the lumen of the stomach, or it may invade the stomach wall, causing it to thicken. As the tumor grows, the lumen narrows to the point of obstruction. The remainder of the stomach becomes extremely dilated due to the blockage, and pain results from pressure on nerve endings. Infection frequently accompanies cancer, which causes additional pain. Because pain is not an early sign, carcinoma of the stomach may be very advanced before it is detected. It may even have spread to the liver and surrounding organs through the lymph and blood vessels. Early symptoms are vague and include loss of appetite, heartburn, and general stomach distress. Blood may be vomited or appear in the feces. Pernicious anemia generally accompanies _______ because the gastric mucosa fails to secrete intrinsic factor. The etiology of this malignancy is not known, but current research suggests an association with the consumption of preserved, salted, cured foods and a diet low in fresh fruits and vegetables.

vomiting

_______ is a sign, not a disease. _______ is a protective response to the presence of an irritant, infection, distention, or a blockage. These stimulate sensory nerve fibers, and the message is conveyed to the _______ center in the medulla of the brain. Motor impulses then stimulate the diaphragm and abdominal muscles, which squeeze the stomach. The sphincter at the base of the esophagus opens and the gastric contents are regurgitated. A feeling of nausea often precedes _______. The cause of the nausea may be factors other than a gastric or intestinal irritant. Motion sickness produces this effect. A very unpleasant smell or sight can cause nausea with possible subsequent _______.

appendicitis

_______ is an acute and painful inflammation of the appendix. _______ can occur at any age, but it is more common among males before puberty to age 25. The wormlike shape of the appendix and its location on the cecum make it a trap for fecal material, which contains bacteria, particularly Escherichia coli. Figure 9-8 Image download failed. illustrates this potential site of infection. Obstruction with fecal material and infections cause the appendix to become swollen, red, and covered with an inflammatory exudate. Because the swelling interferes with circulation to the appendix, it is possible for gangrene to develop. The appendix then becomes green and black. The wall of the appendix can become thin and rupture, spilling fecal material into the peritoneal cavity, causing peritonitis. Before antibiotic treatment, peritonitis was almost always fatal. Diagnosis depends on physical exam. The pain of _______ varies, often beginning in the middle of the abdomen and shifting to the lower right quadrant. Patients may walk or lie bending over, and draw the right leg up to the abdomen to seek pain relief. Other diagnostic signs and symptoms include nausea, vomiting, fever of between 99°F and 102°F, and elevated white blood cell count. Untreated _______ is fatal, and surgery must be performed before rupture occurs.

gastroenteritis

_______ is an inflammation of the stomach and intestines. Symptoms include anorexia, nausea, vomiting, and diarrhea. The onset may be abrupt, with rapid loss of fluid and electrolytes. Possible causes are bacterial or viral infection, chemical toxins, lactose intolerance, or other food allergy, although the actual cause is not always clear. Treatment replaces fluid and nutritional requirements, including the lost salts. Antispasmodic medications can control the vomiting and diarrhea. Food contaminated with human or animal feces may carry microorganisms that cause _______ and food poisoning. Escherichia coli is a normal inhabitant of human or animal intestines. Certain strains may cause disease, such as traveler's diarrhea, or more serious diseases, such as hemolytic uremic syndrome, in which toxins cause potentially fatal shutdown of the kidneys. To prevent infection, cook meat thoroughly and practice good hygiene in the kitchen. One of the common forms of food poisoning is caused by the bacterium Salmonella. These bacteria invade the intestinal mucosa and cause sudden, colicky abdominal pain, nausea, vomiting, and sometimes bloody diarrhea and fever that begins approximately 6-48 hours after eating contaminated food and lasts up to 2 weeks. A stool culture can identify the bacteria. Salmonella food poisoning (salmonellosis) is associated with contaminated eggs and poultry, but most any food may harbor the bacteria. Treatment usually consists of replenishing water, electrolytes, and nutrients. Older adults, young children, and immunocompromised people are at risk of developing serious infection, and they may require more intervention, including a short course of antibiotics and antidiarrheal medications.

celiac disease

_______ is characterized by poor nutrient absorption. _______ affects about 2 million Americans, or 1 in 133 people. _______ seems to be genetic, may involve immune dysfunction, affects twice as many females as males, and is more common among whites of European ancestry. It is caused by intolerance to gluten, a protein component of wheat.

cancer of the colon and rectum

_______ is the fourth leading cause of death from cancer in the United States. The incidence in men and women is roughly equal. Longstanding ulcerative colitis and familial polyposis of the colon each increase the risk for cancer of the colon. Familial polyposis is a hereditary disease in which numerous polyps develop in the intestinal tract. The polyps usually give no symptoms unless a malignancy develops. Another factor associated with risk for colon cancer is a diet high in red meat and low in dietary fiber. The symptoms vary according to the site of the malignancy. A change in bowel habits, diarrhea, or constipation is symptomatic. As the tumor grows, there may be abdominal discomfort and pressure. Blood often appears in the stools, and continuous blood loss from the malignant tumor causes anemia. The mass can partially or completely obstruct the lumen of the colon. As the tumor invades underlying tissue, the cancer cells spread through the lymph vessels and veins. Colorectal cancer is diagnosed with a digital rectal examination and CT. Colorectal cancer grows slowly, tends to remain localized, and is thus potentially curable with early diagnosis. As in all cancers, early detection and treatment are essential to prevent its spread. Most malignancies of the large intestine are in the rectum or the sigmoid colon, which makes their detection and removal easier than malignant tumors in other areas of the digestive tract. Chemotherapy is used when the tumor has metastasized or if residual masses remain inoperable. If sections of the colon are removed, a colostomy may be necessary.

gallstones

_______________ are precipitated bile components in the gallbladder and bile ducts. _______________ and gallbladder disorders (cholecystitis, discussed in the following subsection) are common, affecting about 1 million Americans per year. _______________ affect twice as many women as men. Risk factors include gender (affects women more often), obesity, age, and family history. The stones arise in the gallbladder when the bile composition changes or when gallbladder muscle activity reduces, as it may during pregnancy, use of oral contraceptives, diabetes mellitus, obesity, cirrhosis, and pancreatitis. The stones consist principally of cholesterol, bilirubin, and calcium when in excess. _______________, also called biliary calculi, may be present in the gallbladder and give no symptoms. There may be one gallstone present or several hundred, which can be large or small (Figure 9-12 ) Small stones, referred to as gravel, can enter the common bile duct and cause an obstruction with excruciating pain.

hemmorhoids

_______________ are varicose veins in the lining of the rectum near the anus. _______________ may be internal or external. A physician can observe internal _______________ with a proctoscope, a hollow tube with a lighted end. External _______________ can be seen with a handheld mirror. Causes of _______________ include heredity, poor dietary habits, inadequate fiber, overuse of laxatives, and lack of exercise. Straining to have a bowel movement can cause bleeding or cause the hemorrhoid to prolapse, or come through the anal opening. _______________ frequently develop during pregnancy because of pressure from an enlarged uterus. Treatment includes adding fiber and water to the diet and stool softeners to reduce straining and subsequent inflammation. Medicated suppositories and anorectal creams relieve pain and reduce inflammation.

dysentary

_______________ is an infectious disease with acute inflammation of the colon. _______________ is relatively uncommon in the United States, although outbreaks occur when food or water sanitation break down. Worldwide, _______________ is the leading cause of death from infectious disease in young children. Risk factors include poor sanitation, being under age 6 and over age 65, and having immune deficiency. Bacteria, parasitic worms, and other microorganisms can cause _______________. The protozoan Entamoeba histolytica, which is transmitted in feces-contaminated food and water, causes amebiasis, also called amoebic _______________. Amoebic _______________ is uncommon in the United States and is usually found among immigrants arriving from countries with poor water quality and sanitary procedures. American travelers acquire amoebic _______________ when drinking contaminated water abroad.

cholectcystitis

_______________ is an inflammation of the gallbladder usually associated with gallstones (cholelithiasis). Acute _______________ is most common in middle age. Risk factors include age, being female, and having gallstones. Symptoms are related to the swelling of the gallbladder. Pain occurs under the right rib cage that radiates to the right shoulder. At this point, the gallbladder can usually be palpated. Chills and fever, nausea and vomiting, belching, and indigestion are symptoms; in chronic _______________ these symptoms occur especially after eating fatty foods. The presence of fat in the duodenum stimulates the gallbladder to contract, which causes pain. Prolonged inflammation causes the walls of the gallbladder to thicken, making it impossible for the gallbladder to contract properly. Serious complications can result from _______________. Lack of blood flow because of the obstruction brought about by the swelling can cause an infarction. With the death of the tissues, gangrene can set in. An acutely inflamed gallbladder might require surgical removal. A complication of chronic _______________ is that bile accumulates in the bile ducts of the liver. This causes necrosis and fibrosis of the liver cells lining the ducts. This is another form of cirrhosis, biliary (bile) cirrhosis.

Cirrhosis

_______________ is chronic destruction of liver cells and tissues with a nodular, bumpy regeneration. _______________is the 12th leading cause of death in the United States, killing about 26,000 people each year. Alcoholic _______________, the most common type of _______________, is described here. This disease is also called portal, Laennec, or fatty nutritional _______________(an accumulation of fat often develops within the liver). The exact effect of excessive alcohol on the liver is not known, but it may be related to the malnutrition that frequently accompanies chronic alcoholism, or the alcohol itself may be toxic. The normal liver is composed of a highly organized arrangement of cells, blood vessels, and bile ducts. A cirrhotic liver loses this organization and cannot function. Liver cells die and are replaced by fibrous connective tissue and scar tissue, which has none of the liver cell functions. At first, the liver is generally enlarged due to regeneration but then becomes smaller as the fibrous connective tissue contracts. The surface acquires a nodular appearance, sometimes called a "hobnailed" liver. The changes of _______________impair blood circulation through the liver. As a result, high pressure builds in vessels of the abdomen and in other areas. The esophageal veins swell, forming esophageal varices. Abdominal organs such as the spleen, pancreas, and stomach also swell. These organs and vessels may hemorrhage, causing hemorrhagic shock. Hemorrhage of varices in the stomach or intestines may cause vomiting of blood, or hematemesis. A characteristic symptom of _______________is distention of the abdomen caused by the accumulation of fluid in the peritoneal cavity. This fluid is called ascites and develops as a result of liver failure. The pressure within the obstructed veins forces plasma into the abdominal cavity. This fluid often must be drained. When the liver fails to produce adequate amounts of albumin, an albumin deficiency, hypoalbuminemia, develops and fluid leaks out of the blood vessels, causing edema. Because the necrotic cells of the cirrhotic patient fail to produce albumin, ascitic fluid develops, as does edema, particularly in the ankles and legs. Blockage of the bile ducts also follows the disorganization of the liver. Bile accumulates in the blood, leading to jaundice and, because bile is not secreted into the duodenum, clay-colored stools. The excess of bile, carried by the blood to the kidneys, imparts a dark color to urine. Other signs are related to the fact that the diseased liver cannot perform its usual biochemical activities. Normally, the liver inactivates small amounts of female sex hormones secreted by the adrenal glands in both males and females. Estrogens then have no effect on the male, but the cirrhotic liver does not inactivate estrogens. They accumulate and have a feminizing effect on males. The breasts enlarge, a condition known as gynecomastia, and the palms of the hands become red because of the estrogen level. Hair on the chest is lost, and a female-type distribution of hair develops. Atrophy of the testicles can also occur. ___________ of the liver from chronic alcoholism. The damaged liver cells are unable to carry out their normal function of detoxification, so ammonia and other poisonous substances accumulate in the blood. Elevated ammonia causes neurologic disorders, including confusion, disorientation, stupor, and a tremor called asterixis or "liver flap." Elevated ammonia can lead to somnolence (abnormal sleepiness) and hepatic coma, a cause of death in cirrhosis.

Diarhea

_______________ is the frequent passage of unformed, watery stools that results when the contents of the small intestine are rushed through the large intestine. _______________ is a sign, not a disease. In an episode of _______________, the large intestine cannot reabsorb water from feces because peristalsis in the intestine is intensified. Intestinal infections and food poisoning increase intestinal motility or impair water absorption by mucosal cells. Anxiety and stress can trigger this increased motility of the large intestine.

constipation

_______________ is the inability to eliminate feces from the colon and results when feces become hard and dry. Poor habits of elimination, dehydration, and low-fiber diets may cause _______________. Defecation should be allowed to occur when the defecation reflexes are strong. Otherwise, feces remain in the colon too long, excessive water reabsorption occurs, and the feces become dry, making elimination difficult. A diet containing adequate amounts of fiber aids elimination by providing bulk, which stimulates intestinal motility. Fiber is obtained from fresh fruits, vegetables, and cereals.

Irritable bowel syndrome or spastic colon

_______________ or ______________ is relatively common, occurring in 20% of American adults and affecting more women than men. Irritable bowel is marked by diarrhea, constipation, abdominal pain, and gas. The difference between a spastic or irritable colon and the diseases already discussed is that the _______________has no lesion, no tumor, and no ulceration. It is a functional disorder of motility, the movement of the colon. The pain is probably caused by muscle spasms in the wall of the intestine.

hepatocarcinoma

_______________, or cancer of the liver, is a rare primary malignancy of the liver with a high mortality rate. While liver cancer comprises 1% of all cancers in the United States, it accounts for 6% and 2% of cancer deaths in men and women, respectively. Liver cancer is most prevalent in men over age 60, and the incidence increases with age. Most cancer found in the liver is secondary, a result of metastasis from cancer in other organs, especially the colon, rectum, stomach, pancreas, esophagus, lung, or breast. Primary cancer of the liver is caused chiefly by viral hepatitis and cirrhosis. Other causes of liver cancer may include aflatoxin, a toxin from a mold that grows on peanuts and rice. The symptoms of _______________ vary according to the site of the tumor. If the tumor obstructs the portal vein, ascites develops in the abdominal cavity, as it does in cirrhosis. If the fluid contains blood, a malignancy is indicated. A tumor blocking the bile duct will cause jaundice. General symptoms may include loss of weight and an abdominal mass and pain in the upper right quadrant of the abdomen. Diagnosis includes serum levels of enzymes that arise from diseased liver tissue, but correct diagnosis depends on needle biopsy or open biopsy. Prognosis for cancer of the liver is poor because usually the malignancy has developed elsewhere and has spread to the liver.

jaundice

_______________, or icterus, is a yellow or orange discoloration of the skin, tissues, and the whites of the eyes. _______________ is frequently associated with liver disease. It is caused by a buildup of bilirubin, a yellow pigment derived from the breakdown of hemoglobin that is normally excreted in bile and urine. _______________ results from liver disease such as cirrhosis or hepatitis, inflammation of the gallbladder or bile ducts, gallstones, or hemolytic anemia.

oral cancer

___________________ is a malignant tumor originating within the oral tissues, most often a squamous cell carcinoma. Mouth and throat cancer ranks 11th among the leading causes of cancer death worldwide. Most of these cancers appear on the floor of the mouth, tongue, and lower lip. An aggressive form of the cancer occurs on the upper lip. While the causes remain unknown, it is clear that tobacco, smokeless tobacco, and alcohol use are major risk factors, and it appears that use of alcohol and tobacco in combination increases the risk. Treatment for lip and tongue cancer includes surgical removal. Radiation therapy may be used to treat local cancers on the floor of the mouth. This cancer cannot be prevented, but people can eliminate known risk factors such as smoking and alcohol use.

Cancer of the esophagus

___________________ is a malignant tumor that arises within its tissues. The disease ranks sixth among leading causes of cancer death worldwide. ___________________ occurs most commonly in men over age 60 and is nearly always fatal. Like mouth cancer, tobacco and alcohol use are major risk factors. The cancer narrows the esophageal lumen, causing the principal symptom of dysphagia. The obstruction causes vomiting, a bad taste in the mouth, and bad breath. Esophageal cancer is accompanied by weight loss because of the inability to eat. Diagnosis requires CT or endoscopy. The cancer frequently metastasizes early into adjacent organs, usually the lungs and liver, and to remote sites through the lymph vessels. Because of early metastasis, the prognosis for esophageal cancer is poor. Esophageal cancer cannot be prevented, but its risk factors can be avoided.

esophagatitis

___________________ is inflammation of the lining of the esophagus. The prevalence is unknown but is related to risk factors such as old age, obesity, and pregnancy. ___________________ causes burning chest pains, "heartburn," which can resemble the pain of heart disease. The pain may follow eating or drinking, and some vomiting of blood may occur. The most common trigger of ___________________ is a reflux, a backflow of the acid contents of the stomach.

oral inflammation or stomatitis

___________________, or _____________________, is the inflammation of oral tissue. Depending on the cause, ___________________may appear as patches, ulcers, redness, bleeding, or necrosis. The prevalence of ___________________is unknown. It occurs mostly among those with risk factors such as immune deficiency and long-term antibiotic use. ___________________is usually caused by viruses. However, ___________________may also be caused by bacteria and fungi, or it may be a sign of a systemic infection. Streptococci are a common cause of oral and throat bacterial infections, resulting in red, swollen mucosa. Bacteria also cause canker sores, small circular lesions with a red border. These painful lesions heal without scars after a week. Neisseria gonorrhoeae, the cause of the sexually transmitted disease gonorrhea, causes painful ulcerations in the mouth and throat. The sexually transmitted bacterium Treponema pallidum causes syphilis, which causes oral chancres (small sores associated with the onset of syphillis) and ulcerations. These bacterial infections are treated with antibiotics. Herpes simplex is a common cause of oral virus infections. Transmitted by genital-oral contact, herpes simplex type 2 causes vesicles that rupture to form ulcers. These lesions can appear inside and outside the mouth. Herpes simplex type 1 can be transmitted by oral-oral contact through saliva, and it can be transmitted from mouth to genitals. Pain from herpes lesions makes eating, drinking, and swallowing difficult. The symptoms typically subside within 2 weeks when the viruses move from the area of the lesion to nerve tissue known as ganglia. The infection can be reactivated following stressful events or suppression of immune function. Treatment is aimed at reducing inflammation and pain with systemic anti-inflammatory and analgesic medications or topical anesthetics. The fungus Candida albicans is normally present in the mouth in low levels but can grow excessively in newborns or those with immune deficiencies or following long courses of antibiotic or corticosteroid treatment. Called candidiasis or thrush, the fungal infection forms painless white patches that resemble cheese curds. Removing the white patches leaves a raw, damaged mucosal surface. Candidiasis of the esophagus causes throat pain and difficulty swallowing. Antibiotics and antiviral medications are not effective treatments for fungal infections. Oral candidiasis is treated with oral antifungal agents.

chronic atrophic gastritis

___________________is a degenerative condition in which the stomach lining does not secrete intrinsic factor and hydrochloric acid. Intrinsic factor is required for absorption of vitamin B12, and hydrochloric acid aids protein digestion. ___________________may be caused by stomach cancer, chronic alcoholism, or chronic exposure to certain irritants such as alcohol, aspirin, and certain foods. The term atrophic (wasting) suggests that little can be done to treat this disease. No prevention is possible, but underlying diseases or causes should be eliminated.

diverticula

_______are little pouches or sacs formed when the mucosal lining pushes through the underlying muscle layer of the intestinal wall. This condition is called diverticulosis and may cause no harm in itself. Diverticulitis is an inflammation of the diverticula. Diverticulitis occurs when the sacs become impacted with fecal material and bacteria. Diverticular disease is most prevalent in Western industrialized nations where fiber consumption is lowest. About 50% of older adults develop diverticulosis. Risk is associated with age, diet low in fiber, and family history. Diverticulitis causes low, cramping pain, usually on the left side of the abdomen. As inflammation spreads, the lumen of the intestine narrows, an obstruction can develop, and abscesses frequently form. Diverticular disease is diagnosed with CT and endoscopy. Antibiotic therapy, together with a controlled diet, is usually effective. Figure 9-9 Image download failed. shows an example of diverticulitis.

chronic ulcerative colitis

_______is a serious inflammation of the colon characterized by extensive ulceration of the colon and rectum. The prevalence of ulcerative colitis remains unknown but may be as much as 100 per 100,000. Ulcerative colitis occurs primarily in young adults, especially women, and usually begins between ages 15 and 20. No known causes have been found; however, ulcerative colitis may be related to autoimmunity, E. coli infection, stress, or hypersensitivity to certain foods. Typical symptoms include diarrhea with pus, blood, and mucus in the stools and cramplike pain in the lower abdomen. Periods of remission and exacerbation are common in ulcerative colitis. Anemia often accompanies ulcerative colitis because of the chronic blood loss through the rectum. Increased risk for colon malignancy is associated with longstanding ulcerative colitis. Diagnosis is based on colonoscopy and CT in which the colon has a characteristic appearance; the normal pouchlike markings of the colon are lacking, and the colon appears straight and rigid (a "pipestem colon"). Treatment is aimed at reducing symptoms, replacing nutrients, stopping blood loss, and preventing complications. The symptoms may be alleviated by reducing stress, eliminating foods found to trigger symptoms, and taking adrenal corticosteroids such as prednisone and hydrocortisone to control autoimmunity. If these treatments are not effective, surgery and colostomy may be necessary. A colostomyis an artificial opening in the abdominal wall with a segment of the large intestine attached. Fecal waste is evacuated through this opening and collected in a bag. A colostomy may be temporary or permanent depending on the nature of the colon surgery. Although it cannot be prevented, the symptoms of _______can be managed.

hernia

is the protrusion of part of an organ through a muscular wall or body opening


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