Chronic Inflammation Flashcards
Why may chronic inflammation occur?
- Severe damage unresolved within a few days (take over from acute)
- ‘De novo’: some autoimmune conditions, chronic infections, chronic low level irritation (foreign irritation)
- Develops alongside acute: severe, persistent or repeated irritation.
What is chronic inflammation?
- Chronic response to injury with associated fibrosis
What are macrophages?
- Derived from blood monocytes
- Functions: phagocytosis,
processing and presenting antigens to immune system,
synthesis of cytokines, complement, blood clotting factors & proteases
control of other cells by cytokine release.
What are the main cells involved in chronic inflammation?
- Plasma cells: differentiated antibody producing beta lymphocytes
- Eosinophils: allergic reactions, parasite infections, some tumours.
- (Myo)Fibroblasts: recruited by macrophages and makes collagen
What is the function of lymphocytes?
- Beta lymphocytes: differentiate to produce antibodies
- T lymphocytes: control and some cytotoxic functions
What are giant cells?
- Multinucleated cells: fusion of macrophages
- When phagocytosis becomes frustrated
What are the chronic inflammation effects?
- Fibrosis: e.g chronic peptic ulcers, cirrhosis
- Impaired function: e.g chronic inflammation bowel disease
- Atrophy: e.g gastric mucosa, adrenal gland
- Stimulation of immune response: macrophage - lymphocyte interactions.
Why does gastric ulceration occur?
- Imbalance of acid production and mucosal defence
- Acute: alcohol/drugs
- Chronic: Helicobacter pylori
What is chronic cholecystitis?
- Repeated obstruction by gall stone
- Repeated acute inflammation leading to chronic inflammation
- Fibrosis of gall bladder wall
What’s the difference between ulcerative colitis and chron’s disease?
- UC: superficial: diarrhoea, bleeding
- Chron’s disease: transmural: strictures (narrowing), fistulae (abnormal connection between two epithelium lined organs
What is idiopathic inflammation?
- Large and small bowel inflammation
What is rheumatoid inflammation?
- Autoimmune disease
- Localised and systemic immune response
- Localised chronic inflammation -> joint destruction
- Systemic immune response: can affect other organs -> amyloidosis
How does granuloma inflammation arise?
- Persistent, low-grade antigenic stimulation, hypersensitivity
What are the two main parts of a granuloma?
- Epitheloid histiocytes (modified immobile macrophages)
- Lymphocytes
What are the causes of granulomatous inflammation?
- Mildly irritant ‘foreign’ material
- Infections: e.g. Mycobacteria: TB, leprosy
Other: fungi
