Gastro-Intestinal System Flashcards
Define: Leukoplakia
White plaque - keratin precursors in mucous membranes
What are the 2 types of precancerous lesions for mouth and lips?
- leukoplakia
- dysplasia
What causes thrush?
Candida (yeast)
Most common mouth cancer?
Exposed lower lip
Which cancer has a better prognosis: lower lip or tongue?
Lip - 90%
Tongue - 33%
Infection causing inflammation of salivary glands?
Mumps
Define: xerostomia
Dry mouth
Define: pleomorphic adenoma
Mixed tumor of salivary origin (parotid most common, small salivary glands more risky)
Where are salivary tumors most common? Which salivary tumors are most likely to be malignant?
Most common = parotid gland
Most malignant = small / sublingual salivary glands
What parts of the esophagus are most vulnerable to pathological lesions?
Constrictions:
- cricoid
- tracheal bifurcation
- esophageal hiatus
Define: dysphagia
Difficulty swallowing (subjective condition)
Define: odynophagia
Painful swallowing (associated with acute esophageal inflammation)
Define: achalasia
Motor dysfunction related to the esophagus
- incomplete relaxation OR increased resting tone of lower esophageal sphincter
- decreased peristalsis
Degeneration or dysfunction of which nerve(s) may lead to achalasia and/or dysphagia?
Vagus nerve or esophageal myenteric plexus.
General neurodegenerative changes from a variety of disease processes (like demyelination) may also be a factor)
What is a hiatal hernia?
When a portion of the stomach pushes through the esophageal hiatus in the diaphragm.
What are the two types of hiatal hernias, which is more common, and what do they include?
Common (90%)
Sliding hernia — gastroesophageal junction shifted above hiatus
Paraesophageal or Rolling hernia — portion of fundus is reflected upward along the esophagus.
*this is less common and less complicated.
Is acute or chronic esophagitis more common? What are the causes??
Chronic esophagitis is more common.
Causes: chronic reflux, immunodeficiency, achalasia
What are the changes associated with chronic esophagitis?
- inflammation
- erosions
- ulcers
May lead to metaplasia known as Barrett’s esophagus.
What is the primary cause of esophageal varacosities?
Why are they dangerous?
Portal hypertension due to cirrhosis
Danger = up to 50% are fatal on first rupture. Asymptomatic before first rupture.
What are the major risk factors for esophageal carcinoma?
- alcohol abuse
- smoking
- dietary nitrates and aflatoxins
- HPV?
*prognosis is poor
Recall: define hematemesis
Bloody vomit
Which bacteria is most commonly implicated in mucosal disruption of the upper GI tract?
Helicobacter pylori
Motility disruptions contribute to ulcers where?
- delayed gastric emptying
- premature emptying
Delayed - stomach ulcers
Premature - duodenal ulcers
Define: gastritis
Mucosal inflammation, with accompanying:
- discomfort
- indigestion
- vomiting
What are the features of acute gastritis?
- erosive
- variable in severity
- reversible
What are the general features of chronic gastritis?
- non-erosive
- non-hemorrhagic
- range of severity
- superficial / mild
- atrophic / moderate
- gastric atrophy / severe
What are the two classifications of chronic gastritis?
Type A: fundic
- loss of parietal cells in peptic regions
- pernicious anemia
- more likely autoimmune
Type B: antral
- more common*
- mucosal atrophy of antrum
- more likely to involve H pylori
Define: dyspepsia
Indigestion - burning, bloating, gassiness, nausea after starting to eat
Describe acute peptic ulcers
Rapid onset of multiple small lesions that are shallow with ragged edges.
Usually self limiting and reversible.
Describe chronic peptic ulcers. Where do more than 98% of chronic peptic ulcers occur?
Usually solitary lesions in areas exposed to peptic acid.
Distinct punched out mucosal defects with smooth margins. Repair is scar tissue. Tend to be recurring (relapsing/remitting)
98% in stomach or duodenum
When are ulcers painful in the stomach? Duodenum??
Stomach = during a meal (highest HCl production)
Duodenum = 2 to 4 hours after a meal (at the time of gastric empty
H pylori is likely to cause which kind of uclers?
Chronic ulcers in the duodenum (less likely in the stomach)
What are the major complications of chronic ulcers?
- bleeding (30%)
- perforation (5%)
Define: leiomyoma
Smooth muscle tumor, usually benign
What is one possible test to DDX stomach cancer from gastric ulcer?
Antacids should provide relief to ulcers but NOT to tumors / malignancies
Like all cancer, late-diagnosis for stomach cancer has a poor prognosis. Why is late diagnosis common?
Stomach cancer is usually asymptomatic until it is fairly advanced. Advanced sx include:
- weight loss
- abdominal pain (may mimic ulcer but not respond to antacids)
- nausea
- blood loss
What is pyloric stenosis?
What are the causes?
Hypertrophy of pylorus leads to obstruction —> results in projectile vomiting after meals.
Congenital - usually develops 2-4 wks
Acquired - scarring or tumors
Inflammatory bowel diseases common characteristics:
- chronic
- remitting / relapsing
- stress is a trigger
- familial
- young adult onset, and then early retiree spike in onset
- autoimmune implications
- rare in developing countries
What and where are the lesions of Crohn’s?
Skip lesions - multiple granulomatous lesions with “garden hose” thickening of affected segments in the distal ileum
What happens to the mucosa in Crohn’s?
Cobblestone effect —> focal ulcerative defects with fissures creating a cobblestone like texture
Cobblestone effect and skip lesions are part of what condition?
Chron’s disease
What is the medical name for Chron’s disease?
Regional enteritis
Leukoplakia and dysplasia are part of what condition?
Cancer of the mucous membranes of the mouth and lips
What are the words for these types of esophageal dysfunction:
- difficulty swallowing
- painful swallowing
- motor dysfunction
- dysphagia
- odynophagia
- achalasia
Fundic and antral are the subtypes of what condition?
Chronic gastritis
“Punched out” describes the lesions for what condition?
Chronic peptic ulcers
Where in the bowel will Crohn’s and UC appear?
Crohn’s = distal ileum UC = recto-sigmoid region
What and where are the lesions in ulcerative colitis?
Continuous lesions originating in crypt abscesses in the small intestine that form extensive ulcers.
Commonly arising in the rectal-sigmoid area. Extends through small intestine, may enter ileum.
What are pseudopolyps in UC?
Inflamed, hyperplastic areas of mucosal tissue that remain between extensive ulcers / scars. These heavily secrete mucous
Define: steatorrhea
Diarrhea
What is non-tropical sprue?
Gluten-sensitive enteropathy, aka Celiac disease:
Atrophy of villi and columnar cells of small intestine and malabsorption relating to a pathological immunosensitivity to gliadin (glycoprotein in wheat, barley, and rye)
What is tropical sprue?
Malabsorptive disease common in tropical regions —> acute intestinal illness following bacterial infection (often E.coli)
Requires antibiotics and folic acid
What is the common name of intestinal lipodystrophy?
Whipple’s disease
What is whipple’s disease?
Multi system disorder that begins in the intestines:
- macrophages cannot kill T.whipplei due to missing enzyme —> results in foam cells that accumulate, distend villi in small intestine, and block lacteals, leading to malabsorption.
Other organs including heart, liver, lung, and CNS may eventually be affected.
What different sx are expected with a high intestinal obstruction vs a low one?
High = vomiting Low = abdominal distention and decreased bowel activity
3 causes of functional (not mechanical) obstruction:
- vascular disease
- congenital megacolon - Hirschsprung’s disease
- adynamic (paralytic) ileum
How does vascular disease lead to reduced peristalsis?
Ischemia —> infarcts —> eventually necrotic segments = reduced peristalsis
- necrotic sections may rupture
- more likely in diabetics
What is Hirschsprung’s disease?
Congenital megacolon:
missing sections of myenteric plexus, most commonly in recto-sigmoid region. No peristalsis without it
What is adynamic ileus?
Disruption of peristalsis in the ileum due to severe infection, surgery (temporary), shock, or UC
When should you hear peristalsis on an abdominal exam?
Always.
Especially if pt has recently eaten. Stomach silence is bad.
Mechanical causes of bowel obstruction:
- hernia, incarceration (entrapped segment)
- hernia, strangulation
- strictures or adhesions
- volvulus (looped around self)
- intussusception (segment slides into another segment)
What is intussusception?
When one segment of bowel slides into another segment.
Due to straining around an obstruction that cannot be moved (adults) or hyperperistalsis (kids)
What is volvulus?
A loop of intestine twisting around itself
What is an incarceration hernia?
When a herniated bowel segment becomes trapped
What is a “true” diverticulum?
A wall pouch that contains all layers of GI tract. Congenital defect.
What is a “false” diverticulum?
An acquired defect in which mucosa herniates out through muscular layers of GI tract
What is meckel’s diverticulum?
Remnant of yolk sac stalk located in distal ileum
Where are false diverticulum most common?
Colon, especially sigmoid
What population is most likely to get diverticulum?
Elderly (present in >50% of people over 80)
How can one distinguish appendicitis pain and diverticulitis pain?
Diverticulitis = lower left quadrant abdominal pain
Appendicitis = lower right quadrant abdominal pain
Acute LBP and a distinct lack of peristalsis sounds could mean what condition?
Spinal fracture —> send to ER for possible abdominal CT
Define: carcinoid
What cells / organs affected?
Carcinoma in “slow motion”
Slowly progressing growth with late metastasis affecting argentaffin cells most commonly in the appendix and the ileum
What is the most common location for benign polyps of the large intestine?
Recto-sigmoid region of adults over 50
What are the two types of intestinal polyps?
Pedunculated - tubular adenoma = have stalk, stick out from the wall
Sessile - villous adenoma = broad base of attachment to the wall with villous projections
Which kind of intestinal polyps are more common? Which are more likely to become malignant?
Pedunculated (tubular adenoma) = more common
Sessile (villous adenoma) = more likely to be malignant —> usually because they are larger and the more something grows the more likely it becomes cancer
What kind of polyps are most likely to become cancer?
Multiple familial polyposis —> virtually all untreated subjects end up with cancer
Where is colon cancer most likely to appear?
Recto-sigmoid region
Who is at the highest risk for colon cancer?
People over 50 in developed countries
What are the major risk factors for colon cancer?
- multiple familial polyposis
- ulcerative colitis
- low fiber / high animal fat diet
Colon cancer, like stomach cancer, generally has a poor prognosis. Why?
Asymptomatic until late in the disease, and by then it’s too late.
