Chapter 17: Stomach Flashcards
What differentiates Acute Gastritis from Gastropathy?
Causes of each?
- Acute gastritis: when neutrophils are present; autoimmune or H.pylori
- Gastropathy: absence of inflammatory cells; NSAIDs, EtOH, Bile, Stress
Ulcers associated with acute and chronic gastritis may include layers of what type of injury? (hint: mnemonic to remember layers)
- Necrotic debris
- Inflammation
- Granulation tissue
- Scar (fibrosis)
*NIGS
NSAIDs contribute to gastritis by inhibiting what?
COX dependent synthesis of prostaglandin E2 and I2
Presence of _________ above the basement membrane in direct contact w/ epithelial cells is abnormal in all parts of the GI tract and signifies active inflammation (gastritis)
Neutrophils
What is the charactestic profile of foveolar cells and the epithelium in acute gastritis?
- Foveolar cell hyperplasia w/ corkscrew profiles
- Epithelial proliferation
Can gastropathy and acute gastritis be distinguished clinically?
No
How is the response to PPI’s different if the patient is suffering from NSAID-induced gastropathy vs. pain associated w/ bile reflux?
- NSAID-induced may be asymptomatic or have persistent epigastric pain that responds to antacids or PPI’s
- Bile reflux is typically unresponsive to such therapies and may have occasional bilious vomiting
Stress ulcers are most common in individuals with what 3 things?
1) Shock
2) Sepsis
3) Severe trauma
Ulcers occuring in the prox. duodenum and associated with burns or trauma are called?
Curling ulcers
*Think curling irons will burn you!
Gastric, duodenal, and esophageal ulcers arising in persons w/ intracranial disease are termed?
These lesions are caused by direct stimulation of?
Carry a high incidence of?
- Cushing ulcers
- Direct stimulation of vagal nuclei –> hypersecretion of gastric acid
*Carry a high incidence of perforation
How does ischemia play a role in the pathogenesis of stress-related gastric mucosal injury?
- Systemic hypotension –> decreased blood flow due to stress-induced splanchnic vasoconstriction
- Upregulation of inducible NOS
- Increased release of vasoconstictor endothelin-1
Absence of what morphologically in stress-related gastric mucosal injury differs it from chronic peptic ulcers?
Absence of scarring and blood vessel thickening (characteristic of chronic)
What is a Dieulafoy lesion caused by and what can it lead to?
Where are they most often seen?
Bleeding is often associated with?
- Improper branching of submucosal artery w/i wall of stomach
- Mucosal artery 10x normal size
- Most commonly along lesser curvature, near GE junction
- May erode overlying epi and cause gastric bleeding, often assoc. w/ NSAIDs
Gastric antral vascular ectasia (GAVE) can be recognized endoscopically how?
- Longitudinal stripes of edematous erythematous mucosa alternating w/ less severely injured, paler mucosa
- “Watermelon stomach”
While often idiopathic, gastric antral vascular ectasia (GAVE) can be associated with what underlying pathologies?
Patients may present how?
- Cirrhosis and Systemic Sclerosis
- Present w/ occult fecal blood and iron deficiency anemia
Most common cause of chronic gastritis?
Morphology of this organism?
- H. pylori
- Spiral-shaped, curved bacilli
How does atrophic gastritis caused by H. pylori differ from chronic gastritis?
Has a mutlifocal pattern of injury
Who is the primary carrier of H. pylori and how is it transmitted?
- Humans
- Fecal-oral
H. pylori infection most often presents predominantly as a?
Acid production?
- Antral gastritis
- Normal or increases acid production
When inflammation caused by H. pylori is limited to the antrum there is an increased risk of?
Duodenal peptic ulcer
If gastritis progresses to invovle the gastric body or fundus, it’s known as?
What is seen morphologically?
Increases risk for?
- Multifocal atrophic gastritis
- Patchy mucosal atrophy
- Reduced parietal cell mass –> Decreased acid secretion
- Increased risk of gastric adenocarcinoma (intestinal metaplasia)
The virulence of H. pylori is related to which 4 charactersitc features of the organism?
- Flagella -> allows for motility
- Urease -> generates ammonia and increases pH (for survival)
- Adhesins -> enhance bacterial adherence to surface foveolar cells
- Toxins -> such as CagA
Which virulence factor of H. pylori is associated w/ elevated gastric cancer risk and allows for colonization of gastric body causing multifocal atrophic gastritis?
CagA gene
Polymorphisms of which immunologic mediators are associated w/ development of pangastritis, atrophy, and gastric cancer associated w/ H. pylori?
- Increased: TNF and IL-1β
- Decreased: IL-10 (anti-inflammatory)
Which vitamin deficiency is a risk factor for H.pylori-associated gastric cancer?
Iron
Intraepithelial ___________ and subepithelial _________ are characteristic of H. pylori gastritis.
Intraepithelial neutrophils and subepithelial plasma cells are characteristic of H. pylori gastritis.
H. pylori displays trophism for which cells and part of stomach?
Gastric epithelia –> antrum
Intense H. pylori infection can lead to inflammatory infiltrates producing what finding that mimics appearance of early cancer?
Thickened rugal folds
Lymphoid aggregates, some with germinal centers are frequently present in H. pylori gastritis and represent an induced form of?
Potential to transform into?
- Induced form of MALT
- Lymphoma
Pit abscesses often seen with H. pylori gastritis is due to a buildup of?
Neutrophils
H. pylori can be stained with?
Warthin-Starry silver stain
Which characteristics of this image are distinguishing features of H. pylori gastritis?
- Lymphoid aggregates w/ germinal centers
- Abundant subepithelial plasma cells in superficial lamina propria
Which tests can be used in the diagnosis of H. pylori infection?
- anti-H.pylori Abs test
- Fecal bacterial detection
- Urease breath test
Effective treatment for H. pylori infection includes combinations of?
Antibiotics and PPIs
How does the location of autoimmune gastritis differ from that of H. pylori?
Typically spares the antrum and affects the body
- Associated w/ hypergastrinemia
Autoimmune gastritis is characterized by 5 findings (i.e., Abs and deficiencies)?
- Abs to parietal cells and IF
- Reduced serum [pepsinogen I]
- Endocrine cell hyperplasia
- Vit B12 deficiency (due to Abs against IF)
- Defective gastric acid secretion (achlorhydria) –> hypergastrinemia
What type of anemia is associated with autoimmune gastritis?
- Pernicious (megaloblastic) anemia
- Due to loss of IF and decreased absorption of B12
How is the atrophy of autoimmune gastritis different from that of H. pylori-mediated?
- Autoimmune causes DIFFUSE atrophy = achlorhydria
- H. pylori causes mulitfocal (patchy) = NO achlorhydria
Destruction of parietal cell components, including H+,K+-ATPase by what are considered to be the principal agents of injury in autoimmune gastritis?
CD4+ T cells
Autoantibodies to which parietal cell components are most prominently seen in autoimmune gastritis?
Do they cause damage?
- H+, K+-ATPase
- Proton pumps
- IF
*Not pathogenic, because neither secreted IF or proton pumps are accessible to circulating antibodies
Diffuse mucosal damage of the oxyntic (acid-producing) mucosa within the body and fundus of the stomach are characteristic of?
Autoimmune gastritis
What are some of the characteristic findings morphologically in autoimmune gastritis?
i.e., mucosa, inflammatory rxn, suface changes, and presence of which cells?
- Thinned mucosa and loss of rugal folds 2’ to atrophy
- Deeper inflammatory rxn and centered on the gastric glands
- Small surface elevations representing intestinal metaplasia, presence of goblet cells and columnar absorptive cells
Which stain can allow for visualization of endocrine hyperplasia associated w/ autoimmune gastritis?
Immunostains for chromogrannin A
What are the main inflammatory infiltrates seen with autoimmune gastritis?
Lymphocytes, macrophages, and plasma cells
What is the progression of autoimmune gastritis like and what is the median age of diagnosis?
Which sex is more affected?
- Progression to gastric atrophy occurs over 20-30 years
- Median age = 60 yo
- Slightly more women affected (as w/ most autoimmune dz)
Sometimes the clinical presentation of autoimmune gastritis is linked to sx’s of anemia (B12 deficiency), what may the patient present with?
- Atrophic glossitis (smooth and beefy red tongue)
- Epithelial megaloblastosis
- Malabsorptive diarrhea
- Peripheral neuropathy –> paresthesias + numbness
- Spinal cord lesions –> Subacute combined degeneration (loss of dorsal/lateral spinal tracts)
What can be corrected in regards to B12 deficiency thru B12 replacement therapy?
- ONLY anemia
- Neuro changes CANNOT be corrected!
Eosinophilic gastritis most commonly affects what part of stomach?
Increased serum levels of?
Associated w/ allergic rxns in children to what?
- Antral or pyloric regions
- Increased serum IgE levels
- Cow’s milk or soy protein
Lymphocytic gastritis (Varioliform Gastritis) is sometimes associated w/ what underlying disease?
Most often in which gender presenting with what sx’s?
- Celiac Disease
- Women presenting w/ non-specific abdominal sx’s
What is the distinctive endoscopic appearance of Lymphocytic gastritis (Varioliform Gastritis)?
Histologically there is an increase in the # of which immune cells?
- Thickened folds covered by small nodules w/ central apthous ulceration
- Intraepithelial T lymphocytes
What is the most common specific cause of Granulomatous Gastritis in Western populations?
Other causes?
- Chron disease (most common) –> noncaseating granulomas
- Sarcoidosis
- Infections (mycobacteria, fungi, CMV, and H. pylori)
What are the risk factors for PUD (10 of them from table)?
- H.pylori infection
- Cigarette use (synergizes w/ H.pylori )
- COPD
- Illicit drugs
- NSAIDs
- Alcoholic cirrhosis
- Psychological stress
- Endocrine cell hyperplasia
- ZE syndrome
- Viral infection (CMV, herpes simplex)
Nearly all peptic ulcers are associated w/ what 3 risk factors?
1) H. pylori
2) NSAIDs
3) Cigarette smoking
Most common form of PUD occurs where in stomach and is associated with what?
Levels of what will be increased and decreased?
- Gastric antrum or duodenum as result of chronic H. pylori-induced antral gastritis
- Increased gastric acid secretion
- Decreased duodenal HCO3- secretion
A new group of duodenal PUD patients >60 yo have emerged recently as a result of what?
Presence of what can increase risk?
- Increased NSAID use
- Especially when low-dose aspirin (for CV benefit) is combined w/ other NSAIDs
- Facilitated if concurrent H. pylori infection is also present
How can cigarette use and CV disease contribute to PUD?
Reduced mucosal blood flow, oxygenation, and healing
Where in the duodenum are peptic ulcers most commonly seen?
Involve what part of the wall?
- Prox. duodenum near the pyloric valve
- Anterior duodenal wall
Grossly how does the classic peptic ulcer appear?
Sharply punched-out defect w/ hemorrhage and fibrosis
*Is virtually diagnostic
Perforation of a peptic ulcer into the peritoneal cavity is considered what?
How may this be detected clinically?
- Surgical emergency
- Detection of free air under the diaphragm on upright radiographs of abomen
What is a possible complication due to the scarred vessel walls and thickening of vessels seen in PUD?
Life-threatening hemorrhage
What is the most frequent complication associated with PUD?
Bleeding
*May be first indication of an ulcer