GI pathology Flashcards
- Diseases of the GI tract can be classified as:
– Developmental disorders
– Inflammatory diseases
– Functional disorders
– Circulatory disturbances
– Neoplastic diseases
functions of the GI
esphogeal dx’s
– Hiatal hernia
– Reflux esophagitis
– Barrett esophagus
– Achalasia
– Esophageal varices
– Esophageal cancer
stomach dx’s
– Acute gastritis
– Chronic gastritis
– Peptic ulcer disease
– Stomach cancer
SI dx’s
– Meckel diverticulum
– Bowel obstruction
– Herniation
– Adhesions
– Intussusception
– Volvulus
– Adenocarcinoma
– Carcinoid tumor
LI dx’s
– Pseudomembraneous colitis
– Diverticulosis
– Crohn disease
– Ulcerative colitis
– Adenomatous polyps
– Colon cancer
Layers of the GI
- Mucosa
– Epithelium
– Lamina propria
– Muscularis mucosae - Submucosa
- Muscularis propria: inner circular and outer longitudinal
- adeventitia and serosa
Important Clinical Symptoms and Signs Relating to the GI System
- Dysphagia
- Vomiting
- Hematemesis
- Hematochezia
- Melena
- Diarrhea
- Constipation
- Odynophagia
- Dysphagia
- Vomiting
- Dysphagia –difficulty in swallowing
- Vomiting –expulsion of stomach contents through the mouth
- Hematemesis
- Hematochezia
- Hematemesis –vomiting of fresh, red blood
- Hematochezia –bright, red blood in stool
Melena
* Diarrhea
Melena –black, tarry feces
* Diarrhea –frequent, loose, watery bowel movements
- Constipation
- Odynophagia
- Constipation –hard feces that are difficult to eliminate
- Odynophagia –painful swallowing
subspecialty and types
Fiberoptic Endoscopy
Gastroenterology –a subspecialty
of Internal Medicine
* Esophagogastroduodenoscopy
(EGD) –upper GI endoscopy
* Colonoscopy –lower GI endoscopy
esphogus layers
- Mucosa
– Epithelium
– Lamina propria
– Muscularis mucosae - Submucosa
- Muscularis
Clinical Symptoms and Signs of
Esophageal Disease
- Dysphagia –difficulty in swallowing
- Odynophagia –pain on swallowing
- Heartburn –a burning behind the sternum -GERD
- Acid regurgitation into the mouth –a sign of GERD
type of disorder? dysfunction of? presentation?
Achalasia
a Functional (Motor) Disorder
* Dysfunction of ganglion cells of myenteric plexus (Auerbach plexus) prevents proper relaxation of lower esophageal sphincter - a motility disorder
* Presents with: Dysphagia, regurgitation, halitosis and proximal dilation
demo? dx? signs? increased risk for?
Plummer-Vinson Syndrome
(Paterson-Kelly Syndrome)
- Scandinavian, Northern European women
- Severe Fe-deficiency anemia
- Mucosal atrophy - atrophic glossitis
- Esophageal webs - dysphagia
- Increased risk for squamous cell carcinoma
– Esophagus
– Oropharynx
– Posterior Oral Cavity
usually form where?
Esophageal Varices due to:
- Portal hypertension produces venous dilation
usually develop in lower portion
leads to? mortality? advanced chirrhosis?
rupture of esphogeal varices
- Rupture leads to hematemesis and massive upper GI bleed
- Rupture of a varix is associated with high mortality
- Rupture of a varix accounts for half of the deaths in advanced cirrhosis
Mallory-weiss syndrome
- Mallory-Weiss tears are seen in chronic alcoholics, where violent retching causes esophageal lacerations
and hemorrhage
mallory weiss syndrome
Hiatal Hernia
- Diaphragmatic hernia - widened diaphragmatic hiatus allows protrusion of the stomach through the diaphragm
- Gastroesophageal junction pulled into thorax causing GERD
presents with? risk for?
Barrett Esophagus
- Gastric metaplasia of lower esophageal mucosa - columnar epithelium replaces stratified squamous epithelium
- Presents with: Odynophagia, ulceration, hemorrhage
- at risk for Adenocarcinoma (now glandular tissue not squamous)
forms of esphogeal cancer
- Squamous cell
carcinoma - Adenocarcinoma -
Barrett esophagus
esphogeal cancer may present with
- Dysphagia due to
narrowing of lumen or
interference with
peristalsis
Esophageal Squamous Cell Carcinoma
* demo? prognosis?
* common? US?
* where is esphogus?
* risk factors?
- Older adults, geographical variation,
poor prognosis - Squamous cell carcinoma most
common world-wide, but
adenocarcinoma of esophagus is
more common in the United States - Most common in middle third
- Alcohol and tobacco, Plummer-
Vinson syndrome, diet influence
incidence
SCC of LE
Esophageal Adenocarcinoma
* where?
* risk factor?
* More common in US?
- Lower segment
- Barrett esophagus is a risk factor
- More common than squamous carcinoma in United States
progression of esphogeal adenocarcinomma
from lower portion esphogus
adenocarcinoma
stomach portions
cardia cell types
mucous cells
fundus cells
paritel, cheif and endocrine
body cells
paritel, cheif, endo
pylorus cells
mucus, endo, d cells
parietal cells release
HCL and IF (B12)
chief cells release
pepsinogen
endocrine/G cells release?
gastrin
Gastritis
- Inflammation of the
gastric mucosa
- Acute gastritis –
erosive, due to irritants
and NSAIDs
- Chronic gastritis –
erosive or non-erosive infectious or autoimmune
Acute Erosive Gastritis
* presentation
* erosions?
* causes?
* One of the major causes
of what in alcoholics?
- Epigastric burning, pain, nausea, vomiting
- Shallow erosions
- Causes: Asprin, NSAIDs, alcohol, stress, shock, sepsis
- One of the major causes of hematemesis in alcoholics
infectious chronic gastritis
the most common form of chronic gastritis is due to infection by Helicobacter pylori
AI chronic gastritis
autoantibodies to parietal
cells
Helicobacter Pylori Gastritis can lead to:
- Peptic ulcer disease
- Adenocarcinoma
- MALT Lymphoma (H. pylori is a potential human carcinogen)
gram/shape? biopsy/stain? breath test? Ab test?
H pylori
- Gram negative s-shaped rods
- Biopsy and silver stain
- Urea breath test
- Antibody test for H. pylori
additional path formed?
AI atrophic gastritis
- Autoantibodies against gastric parietal cells causes Gastric mucosal atrophy
- No intrinsic factor, low serum vitamin B12, pernicious anemia
erosion depth? due to?
Gastric Stress Ulcers
- Deeper than erosions, may extend to
muscularis - Severe stress - ICU patients (shock,
trauma, burns, sepsis)
solitary? mainly occur where?
peptic ulcer dx
- Most peptic ulcers are generally solitary lesions
- Most occur in the duodenum - 98% are located in the duodenum and stomach
demarcaation? base? chronic ones may exhibit what?
Characteristics/appearence? of Peptic Ulcers
Sharply-demarcated ulcer with a clean, smooth base
* Chronic lesions may exhibit puckering due to fibrosis
peptic ulcer
blood loss? signs? major cause of death?
Clinical Course of Peptic Ulcer Disease
- Acute/chronic blood loss
- Nausea, vomiting, hematemesis, melena/ heamtocheza
- Perforation - major cause of death in PUD
immeadiate and delayed pain relative to ulcer location
Immediate pain – gastric ulcer
Delayed pain - duodenal ulcer
Etiology of Peptic Ulcers
* factors? result?
* Infection by ?
* Drugs?
* Neuroendocrine?
- Multifactorial disease, decreased mucosal resistance
- Infection by H. pylori
- Drugs –aspirin, NSAIDs
- Neuroendocrine –hormonal hypersecretion syndromes
– Cushing Syndrome –corticosteroids
– Zollinger-Ellison Syndrome –gastrin
peptic ulcer formation diagram
bleedings (types and signs)? perforation? stenosis? pancreas?
Complications of Peptic Ulcer Disease
- Minor hemorrhage –melena, iron deficiency anemia
- Major hemorrhage -hematemesis
- Perforation - peritonitis
- Stenosis and obstruction
- Penetration into pancreas
Zollinger-Ellison Syndrome
Gastrin-secreting tumor in pancreas or duodenum (“gastrinoma”)
* Hypergastrinemia causes hypersecretion of gastric acid
* Severe peptic ulcer disease with multiple ulcers in unusual locations
demo/prognosis? dietary? predepositions to this?
gastric adenocarcinoma
- Older individuals, poor
prognosis - Smoked fish –nitrosamines
- Predispostion to gastric
cancer
– H. pylori infection
– Chronic atrophic gastritis
– Gastric adenomatous polyps
Gastric Adenocarcinoma location
- Lesser curve of antro-
pyloric region