Transcript PathoPhysiology

PathoPhysiology
Gastric Bleeding due to
Peptic Ulcer Disease
Gastroduodenal Mucosal Defense
Harrison’s Principles of Internal Medicine 17th ed.
Causes of Mucosal Damage
• Cigarette Smoking
• Psychological Stress
• Genetic
Predisposition
• Diet
Increased intake of:
– Alcohol
– Caffeine
Harrison’s Principles of Internal Medicine 17th ed.
H. pylori-induced Peptic Ulcer Disease
• Risk-factors of H. pylori infection
– Poor socioeconomic status
– Less education
• Mode of Transmission
– Oral-oral
– Fecal-oral
• Factors Affecting Infection
– Bacteria’s motility
– Ability to produce urease
Harrison’s Principles of Internal Medicine 17th ed.
Peptic Ulcer Disease
Bacterial Factors
• Structure
S-shaped rod with
multiple flagella in
one pole
• Adhesins
• Porins
• Enzymes: Urease,
Protease,
Phospholipase
Host Factors
• Duration
• Location
• Inflammatory
Response
• Genetics ??
Harrison’s Principles of Internal Medicine 17th ed.
Cytokine Production
• IL-1 alpha/ Beta
• IL-2
• IL-6
• IL-8
• TNF alpha
• IFN gamma
Inflammatory Response to H. Pylori
H. Pylori binds to class II MHC on
gastric epithelial cells
Recruitment of neutrophils, lymphocytes, macrophages &
plasma cells
Release of Prostaglandin, Substance P, Histamine
Apoptosis
Production of O2 or N2 species
(T cells & IFN gamma)
(neutrophils)
Epithelial cell injury
ULCER
Harrison’s Principles of Internal Medicine 17th ed.
ULCER
Gastrointestinal bleeding