GI Pathology Flashcards
(108 cards)
1
Q
Distinguish between triggers for primary and secondary peristalsis
A
Primary – triggered via swallowing
Secondary – esophageal distention
2
Q
Define achalasia
A
A failure of esophageal smooth muscle fibers to relax causing sphincter dysfunction
3
Q
What is the pathognomonic triad of achalasia?
A
High LES tone, incomplete relaxation of LES when swallowing, no peristalsis
4
Q
List common findings of achalasia
A
Dysphasia, vomiting, dilated upper esophagus, nocturnal regurgitation/aspiration, chest pain
5
Q
How is achalasia usually treated?
A
Calcium channel blocker, manual dilation, LES ablation
6
Q
What is an esophageal spasm?
A
Diffuse and asynchronous contraction of esophageal smooth muscle
7
Q
40% of chest pain that is not cardiac in nature can be attributed to what G.I. dysfunction?
A
Esophageal spasm
8
Q
What are esophageal varices?
A
Large dilations of sub-epithelial collateral veins in esophagus caused by obstruction of blood flow in hepatic portal vein causing portal hypertension
9
Q
List clinical findings of esophageal varices
A
Hematemesis, shock, hypovolemia, upper G.I. bleed
10
Q
What percentage of esophageal variceal bleeds result in patient death and why?
A
50% – the bleeding leads to hypovolemic shock
11
Q
Describe a Mallory-Weiss tear
A
A superficial longitudinal tear in the mucosal layer at the junction of esophagus and stomach
12
Q
What typically causes a Mallory-Weiss tear?
A
Prolonged vomiting, often alcohol related
13
Q
What is Boerhaave’s syndrome?
A
A transmural esophageal laceration causing mediastinitis due to leakage of gastric and esophageal contents into mediastinal space
14
Q
What is the most common kind of tracheoesophageal fistula?
A
Blind esophagus with distal fistula (87%)
15
Q
What condition allows diagnosis of TEF in utero?
A
Polyhydramnios
16
Q
What are complications of a tracheoesophageal fistula?
A
Pneumonia, aspiration, weight loss, regurgitation of food and feeding difficulty
17
Q
What is Barrett esophagus?
A
“Pre-malignant” metaplasia of distal esophagus (squamous cells change to glandular) that increases risk for esophageal adenocarcinoma
18
Q
What is GERD?
A
Gastroesophageal reflux in LES causing burning pain, dysphasia, chest pain, minor hematemesis
19
Q
List the four risk factors for GERD
A
EtOH, smoking, obesity, hiatal hernia
20
Q
What percentage of people with Barrett’s esophagus are diagnosed with esophageal cancer yearly?
A
1%
21
Q
What innervates the upper esophageal sphincter and lower esophageal sphincter?
A
UES – recurrent laryngeal nerve
LES – myenteric plexus
22
Q
List the two pathologic categories of esophagitis and give examples of each
A
Irritative/chemical: EtOH, biliary, chemotherapy, radiation, ulcerative, pill
Infectious: HSV, CMV, candida
23
Q
What is the most common kind of esophageal cancer?
A
Squamous cell carcinoma
24
Q
Which kind of cancer usually occurs due to Barrett esophagus?
A
Adenocarcinoma
25
What are clinical presentations of esophageal cancer?
Dysphasia, weight loss, chest pain, hematemesis, vomiting
26
What is the five-year survival rate for esophageal cancer?
Less than 25%
27
List of potential causes of esophageal obstruction/stenosis
Chronic irritation, cancer, radiation fibrosis, caustic injury, foreign body, Webs, lung cancer
28
What is a Schatzki ring?
A stricture at the lower esophageal sphincter that prevents normal passage of esophageal contents to stomach
29
List protective mechanisms employed by the stomach
Mucosal secretion, tight junctions, bloodflow, bicarbonate secretion, gastric emptying, prostaglandin secretion
30
List some causes of insult to the stomach
Excessive acid secretion, alcohol use, NSAIDs, H. pylori, decreased mucus and bicarbonate production, radiation, chemotherapy, ischemia, delayed gastric emptying, stress/shock
31
Which two substances combine with food in the stomach to produce chyme?
HCl and pepsin
32
List two common causes of dumping syndrome
Vagotomy and diabetic gastroparesis
33
Describe dumping syndrome
Rapid gastric emptying of hyper-osmolar chyme into the small intestine
34
List six clinical findings of dumping syndrome
Bloating, postprandial nausea/vomiting, cramping, diaphoresis, diarrhea, dizziness
35
What G.I. disorder is characterized by bloating, postprandial nausea and vomiting, cramping, diaphoresis, diarrhea and dizziness?
Dumping syndrome
36
What is acute gastritis?
Small diffuse erosions of stomach lining potentially causing hemorrhage and ulcers
37
List 6 clinical findings of acute gastritis
Epigastric pain, nausea/vomiting, hematemesis, melena, anemia, burning discomfort
38
Distinguish between type A and type B chronic gastric inflammation
Type A: autoimmune (antibodies to parietal cells as in B 12 deficiency anemia)
Type B: H. pylori or NSAIDs
39
Describe the nature of chronic gastric inflammation
Lymphocytes and plasma cells accumulate in lamina propria
40
Describe the nature of acute gastric inflammation
Involves neutrophils above basement membrane touching the epithelium causes progressive erosion
"Acute-rophils"
41
What are four causes of acute gastric mucosal inflammation?
NSAIDs, burns, Cushing's disease, stress
42
What are the two major causes of peptic ulcer disease?
H. pylori and NSAIDs
43
How is a peptic ulcer formed?
Upper G.I. tract exposed to pepsin and acid causing damage to mucus, then muscle, then vessels, then eventual perforation with regeneration and scarring
44
What percentage of the population is affected by PUD?
10%
45
List the 4 virulence factors of H. pylori
Flagella, urease secretion, adhesions, toxin secretion
46
What is Zollinger-Ellison syndrome?
A pancreatic tumor that hyper secretes gastrin which increases HCl secretion from stomach causing multiple ulcerations
47
What type of tumor comprises 90% of all stomach cancer?
Adenocarcinoma
48
What are symptoms of gastric cancer?
Dyspepsia, pain, dysphasia
49
List some dietary factors that contribute to gastric cancer occurrence
Consumption of benzo-pyrene and n-nitroso compounds, preserved and smoked foods
50
What type of genetic mutation is a risk factor for gastric cancer?
Mutations in protein that encodes for cadherin that causes breakdown of desmosomes
51
What virus is known to cause 10% of gastric cancer via neoplastic transformation?
EBV
52
What are clinical findings of gastric cancer?
Anorexia, weight loss, epigastric pain, vomiting, melena, GERD
53
How is gastric cancer diagnosed?
By barium swallow, CT scan of abdomen with contrast, endoscopy and biopsy
54
What is an ileus?
Paralyzed bowel due to distention, obstruction, surgery, or inflammation
55
Why are duodenal ulcers not considered cancer precursors?
Acid is a protective feature against cancer
56
What G.I. pathology would be suspected with presentation of the following symptoms: epigastric pain 1-3 hours after eating, relieved by food, pain often at night, bleeding with melena?
Duodenal ulcers
57
What percentage of the population is affected by IBS (irritable bowel syndrome)?
10 to 20%
58
What are the symptoms of IBS?
Abdominal pain, cramping, diarrhea/constipation, flatulence, bloating, anorexia
59
Describe the pathology of IBS
Dysfunction in GI motor/sensory function modulated by CNS
60
Describe the lesions seen in Crohn disease
Transmural, sub-mucosal, non-caseating granulomas, that cause cobblestone appearance of mucosa
61
List clinical findings of Crohn disease
Abdominal pain, cramping, diarrhea, malabsorption, weight loss, fever
62
Why is there less bloody diarrhea in Crohn disease than in ulcerative colitis?
Crohn disease affects submucosa whereas UC affects mucosa
63
What will be visible on CT in patients with Crohn's disease?
Edema, strictures, fistulas, scar tissue, ulcers
64
List distinctions between ulcerative colitis and Crohn disease
UC: typically more of acute presentation, does not have noncaseating granulomas and adhesions, more bloody diarrhea than in Crohn's due to mucosal involvement
65
Which G.I. pathology is recognized by rules of twos?
Meckel's diverticulum
66
What are the rules of two's in Meckel's diverticulum?
2% of population affected, 2 inches from ileocecal valve, 2 inches long, seen within first two years of life
67
How does Meckel's diverticulum present, if at all symptomatic?
Bloody diarrhea or intussusception
68
What are 7 potential causes of acute intestinal obstruction (small bowel obstruction)?
Adhesions, small bowel tumors, hernias, intussusception, infarction, stricture, volvulus
69
Describe the anatomy of a small bowel obstruction
Dilated loops proximal to obstruction with collapsed loops distal to obstruction
70
State the difference between constipation and obstipation
Constipation: lack of food movement
Obstipation: lack of gas movement
71
What is a bowel adhesion?
When two loops of bowel become attached and scar tissue encircles the bowel loop
72
What is the most common cause of SBO?
Abdominal (umbilical) hernia
73
Bowel strangulation leads to which three potential outcomes?
Infarction/ischemia, infection/sepsis, rupture
74
Why is arterial blood gas helpful in diagnosing SBO?
It reveals pH, which (if low) indicates lactic acid buildup due to sepsis
75
Why would ileus be suspected in a post-op patient?
Anesthesia has paralytic effect on bowel
76
What is peritonitis?
Inflammation of peritoneum (serous membrane covering the viscera) due to bacterial or chemical irritation
77
List some common causes of peritonitis
Ruptured peptic ulcer, appendicitis, diverticulitis, ischemic bowel, abdominal trauma (anything that introduces bacteria into peritoneal membrane)
78
What are clinical presentations of peritonitis?
Fever, localized severe abdominal pain with guarding, vomiting, decreased bowel sounds, leukocytosis/elevated ESR
79
List an example of a malabsorption syndrome
Celiac disease
80
What specific gluten content causes a celiac reaction?
Gliaden
81
What two features will a biopsy of celiac tissue show?
Blunting of intestinal villi and anti-gluten antibodies
82
Which type of neoplasm do 10% of celiac patients develop?
Lymphoma
83
Describe the clinical presentation of celiac disease
Weight loss, diarrhea with pale frothy foul-smelling stool, abdominal pain, weakness with anemia, skin rash, glossitis
84
Describe the mechanism of celiac disease
T-cell mediated immune response against gliaden in gluten-containing diet
85
Which three arteries and can be compromised to cause acute mesenteric ischemia?
Celiac, superior mesenteric, inferior mesenteric
86
What are atherosclerosis, embolism, aneurysm, shock, and cardiac failure all risk factors for?
Ischemic bowel disease
87
What are the two watershed zones of the large intestine (that are most susceptible to ischemia)?
Splenic flexure and sigmoid colon
88
Which concurrent diseases usually occur with ischemic bowel disease?
Heart conditions such as atherosclerosis, hypertension, CAD
| Also DM
89
What is the clinical presentation of ischemic bowel disease?
Nausea, vomiting, bloody diarrhea, acute severe abdominal pain, elevated ESR and leukocytosis, venous thrombosis detected on CT
90
Contrast noninvasive an invasive infectious enterocolitis
Noninvasive: superficial epithelium infection producing watery diarrhea
Invasive: deep bowel wall infection producing hemorrhagic diarrhea
91
How is gastroenteritis spread?
Fecal oral route
92
What pathogen causes viral enterocolitis in 6 to 24 month olds resulting in watery diffuse diarrhea?
Rotavirus
93
What pathogen causes the majority of cases of gastroenteritis in adults?
Norwalk
94
List the differences between viral and bacterial enterocolitis
Viral (less severe) – superficial epithelium is infected and destroyed causing osmotic diarrhea and cramping, mid-abdominal pain
Bacterial (more severe) – causes destruction of mucosa, enterotoxin secretion, ulcerations and bleeding
95
List the six most common bacterial causes of enterocolitis
Staph aureus, E. coli, shigella, salmonella, Campylobacter, Clostridium difficile
96
Describe the anatomical progression of ulcerative colitis
Begins in rectum and spreads proximally
97
What are the four clinical findings of ulcerative colitis?
Abdominal pain, bloody diarrhea, fever, anemia
98
Describe ulcerative colitis
Crypt abscesses in the large intestine with PMNs causing confluent and continuous inflammation with mucosal hemorrhages and ulcerations
99
What is it about C. Diff that makes it so aggressive and difficult to treat?
It forms resistant spores and secretes toxins that cause inflammation, hemorrhage and necrosis
100
What's another name for C. Diff (and why)?
Pseudomembranous colitis – because spores form pseudomembranes that adhered to areas of mucosal injury
101
Which type of colonic adenomas are most common, and which type are most rare?
Tubular adenomas are most common
| Villous adenomas are most rare
102
What are some signs that adenomas have progressed to adenocarcinomas in colon?
Bleeding, bowel habit change, secretion of CEA
103
What age should regular colonoscopies begin and how often are they repeated?
At age 50, repeated every 10 years
104
What causes appendicitis?
Obstruction of appendix lumen by fecal matter
105
What are the clinical signs of appendicitis?
Abrupt onset of periumbilical pain with fever, nausea, vomiting, progressing to RLQ pain
106
What is diverticulitis?
Inflammation of diverticula (pouches) in colon wall causing microperforations
107
What is the clinical presentation of diverticulitis?
Acute left lower abdominal pain, fever with leukocytosis
108
What are the four categories of diarrhea? Give an example of each
Secretory (Cholera), osmotic (lactase deficiency), malabsorptive (Celiac, Chrons), exudative (inflammatory bowel disease)
