Week 11: GI, Liver & Pancreas Flashcards
Define dysphagia
difficulty swallowing
Causes of dysphagia (4)
- Disorders that produce a narrowing of the esophagus
- obstructions d/t tumors inside or outside the esophagus
- Lack of salivary secretion
- Impaired esophageal motility
External causes of dysphagia (5)
compression of the esophagus by:
- enlargement of the L atrium of the heart
- aortic aneurysm
- abnormally formed blood vessels
- abnormal thyroid gland
- bony outgrowth from spine or cancer
Define esophagitis
inflammation of esophagus
Causes of esophagitis (3)
- Eosinophilic
- Infection - candida albicans, herpes simplex virus, CMV
- Erosive: chronic acid reflux
Define Barrett’s esophagus, what does it usually lead to
intestinal metaplasia in the esophagus
typically leads to adenocarcinomas
Define hiatal hernia
S/S related to hiatal hernia (5), causes (4)
protrusion or herniation on the upper part of the stomach into the thorax through a tear or weakness in the diaphragm
S/S: chest pain, SOB, heart palpitations, discomfort swallowing food, acid reflux/heartburn
Causes: obesity, constipation, smoking, pregnancy
Define GERD
S/S related to GERD (2), causes (6)
backflow of gastric or duodenal contents or both into the esophagus past the LES
S/S: acute epigastric pain, heartburn
Causes: food/alcohol/cigarettes, hiatal hernia, increased abdominal pressure, medications, NG intubation, weak LES
How does smoking increase the risk of developing GERD? How does obesity?
Smoking: relaxes the LES
Obesity: increased abdominal pressure
Define gastritis, causes (5), s/s (5)
inflammation of the stomach
Causes: infection, stress, injury, drugs, immune disorders
S/S: abdominal pain, indigestion, bloating, N/V, pernicious anemia
Identify: exposure (2); infection; and genetic disorder (2) related to gastritis.
Exposure: gastric banding surgery, trauma
Infection: H.pylori
Genetic disorder: Type I diabetes, Hashimoto’s
Define gastroenteritis; identify two causative agents; and explain the role of inflammation in this process. What are indicators of inflammation; and what are typical clinical consequences of gastroenteritis?
inflammation of the GI tract, mostly within small intestine, also of the stomach
Causative agents: bacterial or viral infections - rotavirus, e. coli and campylobacter jejuni
Indicators of inflammation: evidence of blood in the stool
Clinical consequences: dehydration
Define irritable bowel syndrome
non-inflammatory type disorder, also known as spastic colon or spastic colitis, disorder of entire digestive tract causes recurring abdominal pain and constipation or diarrhea
Underlying cause of IBS
Prevalence
Triggers
Benign or Malignant?
unknown, may involve motor disturbances and reaction to distension irritants or stress
Prevalence: common, twice as common in women as men
Triggers: A variety of substances and emotional factors
Benign - no anatomic abnormality
Define inflammatory bowel disease
Patho
general term for chronic inflammation of the GI tract
Patho: chronic inflammation results in neutrophil infiltration, ulceration, development of fibrosis
Causes of inflammatory bowel disease
Sx (3)
Tx (1)
unknown, associated with genetic, infectious, immunological or psychological factors
Sx: bloody diarrhea, abdominal pain, weight loss (due to malabsorption)
Tx: termination of inflammatory response/promotion of healing
Define Crohn’s disease, what layers are affected?
What is a complication that can occur?
regional enteritis or granulomatous colitis, chronic inflammatory process that can affect any part of the GI tract
affected layers: affects all layers
Complication: fistula or abscess formation and intestinal obstruction
What disease process are skip lesions and cobblestone associated with?
Define each
Crohn’s
Skip lesions: demarcated granulomatous lesions that are surrounded by normal-appearing mucosal tissue
Cobblestone: fissures and crevices cause a cobblestone appearance to the surface of the mucosal layer
Define Ulcerative Colitis, what layers are affected?
What is a complication that can occur (3)?
inflammatory disease of the colon and rectum, produces edema and ulcerations
affected layers: usually affects mucosa only
Complications: perforation of the colon, fatal peritonitis and toxemia, increased r/f colon cancer
Characteristics of ulcerative colitis
- Inflammation is consistent and confluent across the surface
- May see small, focal crypt abscesses that become necrotic and ulcerate
Causes, Sx, Tx of Ulcerative colitis
Causes: unknown, may be r/t abnormal immune response in colon
Sx: constant diarrhea mixed with blood
Tx: reduce acute manifestations, prevent recurrence, avoid irritants
Define nausea vs. vomiting
Nausea: urge to vomit that may occur independently of vomiting or may precede or accompany it
Vomiting: forceful expulsion of gastric contents, increases intra-abdominal pressure along with relaxation of LES causes return of stomach contents to the esophagus and mouth
Define anorexia
loss of appetite or lack of desire for food
Nausea, abdominal pain and diarrhea may accompany it
May result from dysfunction of GI system or other cause
Distinguish between: osmotic and secretory diarrhea and identify one cause of each
Osmotic: Hyperosmotic luminal contents whereby a nonabsorbable substance in GI tract shifts the osmotic balance so that water is drawn into the GI tract - lactose intolerance
Secretory diarrhea: secretory processes increased - Zollinger-Ellison syndrome
Define constipation and explain how: dehydration, lack of exercise, medications can cause constipation.
define: infrequent, incomplete or difficult passage of stools
Define normal-transit vs. slow-transit constipation
Normal-transit: perceived difficulty in defecation, usually responds to increased fluid and fiber intake
Slow-transit: characterized by infrequent bowel movements and is often associated with alterations in intestinal innervation
What typically causes disorders of defecation?
Causes: dysfunction of the pelvic floor or anal sphincter
Define intestinal obstruction and explain/give an example of mechanical (1) and non-mechanical obstructions (3).
Intestinal obstruction: partial or complete blockage of the lumen of the small or large bowel
Mechanical: foreign bodies such as fruit pits, gallstones or worms
Non-mechanical: paralytic ileus, electrolyte imbalances, toxicity
What is the connection between adhesions; strangulation; and tumors and intestinal obstruction?
○ Adhesions and strangulated hernias usually cause small bowel obstructions
Tumors: carcinomas usually cause large bowel obstructions
How can obstruction result in shock?
can occur if obstruction is untreated
Define diverticulosis and identify two causes.
inflammation of diverticular or herniation within the wall of the intestinal tract, accompanied by an inflammatory response usually in sigmoid colon
Causes: - intraluminal pressure: chronic constipation, obesity
- Inflammation: bacterial infection and undigested food
Define peritonitis and explain GI causes (5) and GU causes.
inflammatory response of the serous membrane lining the abdominal cavity and covering internal visceral organs
GI causes: perforated peptic ulcer, ruptured appendix, perforated diverticulum, gangrenous bowel or gallbladder
GU causes: PID
Define malabsorption syndrome
alteration of ability of intestine to absorb nutrients
How are each of the following related to malabsorption: cystic fibrosis; celiac disease; inflammatory bowel disease
CF: thick mucus surrounding organs can lead to poor absorption
Celiac disease: immune-mediated disorder triggered by ingestion of gluten-containing grains
Inflammatory bowel disease: inflamed mucosa more difficult to properly absorb nutrients
How can malabsorption cause anemia; steatorrhea; and edema?
anemia: decreased B12, iron, folic acid), steatorrhea: decreased fat absorption
edema: decreased protein absorption
Definition/causes/sx of Upper GI bleed
Definition/sx of Lower GI bleed
Definition: occult bleeding
Upper GI bleed: esophagus, stomach, duodenum
Causes: bleeding varices, PUD, esophageal tea
Sx: hematemesis, melena (dark, tarry stools)
Lower GI bleed: jejunum, ileum, colon or rectum
Sx: hematochezia (frank bleeding from rectum)
Occult bleeding: usually slow chronic blood loss
Define jaundice and explain the differences between pre-hepatic; hepatic; and post-hepatic jaundice and give one example of each type of jaundice.
Jaundice: yellow or greenish pigmentation of the skin, sclerae and mucous membranes caused by hyperbilirubinemia
Pre-hepatic: may be caused by genetic diseases including sickle cell anemia, thalassemia, glucose-6-phosphate dehydrogenase deficiency, hemolytic uremic syndrome
Hepatic: dysfunction of the liver’s ability to process bilirubin for elimination; commonly caused by hepatitis or cirrhosis
Post-hepatic: problems related to passage of bile through bile ducts that results in obstructive jaundice; commonly caused by gallstones or pancreatitis/pancreatic cancer
How does neonatal jaundice occur?
Neonatal jaundice caused by impaired uptake/conjugation of bilirubin as enzymes not present at birth
What is the normal role of the liver in biotransformation; what generally happens in phase I and phase II reactions?
Biotransformation: detoxification of drugs or alcohol, reactions that convert lipid-soluble or nonpolar molecules into water-soluble or polar substances to facilitation excretion and elimination from the body
Phase I: chemical modifications - cytochrome P450 system
Phase II: conjugation with glutathione
Define hepatitis, causes (4)
Hepatitis: inflammation of the liver
Causes: infection, alcohol abuse, drug intoxication, autoimmune processes
What is the most common cause of drug-induced liver damage?
Acetaminophen
What is nonalcoholic fatty liver disease?
What are underlying conditions associated with NAFLD (4); and a common mechanism that underpins these conditions?
Nonalcoholic fatty liver disease: fatty liver disease that has the potential to progress to cirrhosis and ESLD arising from causes other than alcohol abuse
Associated underlying conditions: Type 2 diabetes, obesity, metabolic syndrome, hyperlipidemia
Common mechanism: unknown, appear at least in part related to insulin resistance
What are the liver function tests that can be done and what do they indicate?
ALT, AST indicate liver cell injury or death
Define liver failure and hepatorenal syndrome and discuss how this occurs in the terminal stages of liver failure?
Liver failure: results when 80-90% of liver function is lost
Hepatorenal syndrome: terminal stages of liver failure with ascites, includes azotemia, increased creatinine and oliguria
Define cholelithiasis
formation of gallstones that obstruct a bile duct
Explain how gallstones are formed; what precipitates from the bile to form gallstones?
Gallstone formation: caused by precipitation of bile components including cholesterol and bilirubin, crystals form into gallstones
Usually cholesterol, calcium salt of bilirubin or calcium carbonate precipitate from bile
What is cholecystitis and the relationship to obstruction and infection.
Cholecystitis: inflammation of the gallbladder
Obstruction: causes accumulation of bile in the gallbladder and increased pressure
How can perforation of the gallbladder result in fever, shock, and jaundice?
Causes systemic inflammatory response
Define/distinguish: acute and chronic pancreatitis.
Acute: reversible inflammatory process of pancreatic acini brought on by premature activation of pancreatic enzymes
Chronic: progressive and permanent destruction of the exocrine pancreas, fibrosis and later stages destruction of the endocrine pancreas
What are major causes of acute pancreatitis (2) and how can this be life-threatening?
Causes: alcohol abuse and cholelithiasis
obstruction that limits drainage of pancreatic fluid, damages multiple body systems
Fx of pancreatitis on GI system (2)
GI: inflammation causes premature activation of enzymes, fluid losses can lead to hypovolemic shock
What are underlying causes (2) of chronic pancreatitis and how can this cause type 1 diabetes?
Causes - chronic alcohol abuse, cholelithiasis
Progressive loss of pancreas parenchyma leads to pathology including Type 1 diabetes
Where does oral cancer occur and what are risk factors?
Oral cancer: lips, pharynx, tongue, soft palate, uvula
Risk factors: tobacco/alcohol use
Why is the liver a common site of secondary tumors?
common site of secondary tumors as liver is responsible for blood filtration to other organs
Define benign vs. malignant liver tumors
Benign: liver cell adenoma, bile duct adenoma
Malignant: arise from hepatocytes (hepatocellular carcinoma or hepatoma) or bile duct epithelium (cholangiocarcinoma)
Complications of esophageal cancer (3) and what are risk factors (3)
causes dysphagia, obstruction, usually in lower two-thirds of esophagus; causes pulmonary complications
Risk factors: tobacco use, alcohol use, diet
Characteristics of stomach cancer (2) and what are symptoms (4)?
gastric changes, adenocarcinoma
sx: weakness, weight loss, loss of appetite, gastric pain
Characteristics of intestinal cancer, risk factors, sx?
adenocarcinomas, usually in large intestine
risk factors: diet, other diseases
Sx: rectal bleeding
Gallbladder cancer: Ranking in GI cancers, prognosis, sx?
5th most common GI cancer, poor prognosis 1% 5 year survival rate
sx: cholecystitis
Pancreatic cancer:
Ranking in causes of death from cancer
Prognosis
Are benign or malignant more common? Which is more life-threatening?
pancreatic cancer is the 4th leading cause of death from cancer in the US, 90% die within 1st year of diagnosis, 4-5% 5-year survival rate
Malignant more common and more life-threatening
Fx of pancreatitis on cardiovascular system (2)
CV: trypsin activates kallidrein, causing vasodilation and increased vascular permeability
Fx of pancreatitis on clotting (2)
Clotting: pancreatic inflammation interferes with vitamin K absorption, resulting in reduced clotting factors; DIC may result
Fx of pancreatitis on immune system (1)
Immunity: infection of pancreas may occur and purulent drainage can erode the retroperitoneum into bowel and pleural space and promote sepsis
Fx of pancreatitis on respiratory system (2)
Respiratory: severe pain can interfere with breathing, resulting in PNA; pancreatic enzymes can enter circulation and damage pulmonary vessels, resulting in pleural effusion
