5. Chronic Inflammation Flashcards
What is the definition of chronic inflammation?
Chronic response to injury with associated fibrosis
In what 3 ways can chronic inflammation arise?
Take over from acute inflammation - if inflammatory stimulus persists and damage is too severe to be resolved within a few days.
De novo - autoimmune conditions, chronic infections, chronic low-level irritation.
Alongside acute inflammation - severe persistent or repeated irritation eg ongoing bacterial infection.
What is the most important characteristic in chronic inflammation?
Type of cell present
What are macrophages derived from?
Blood monocytes
Name 4 functions of macrophages
Phagocytosis
Presentation of antigens to immune system
Synthesis of cytokines, complement component,s blood clotting factors, proteases
Control of other cells by cytokine release
What is the function of B lymphocytes?
Differentiate to produce antibodies
What is the function of T lymphocytes?
Control and some cytotoxic function
Where are lymphocytes found?
Are a normal component of many tissues, and found in chronic inflammation
Name 2 functions of eosinophils
Present in high numbers in allergic reactions
Attack parasite infestations
How are fibroblasts recruited?
By macrophages - respond to chemotactic stimuli
What are plasma cells? When are they present?
Differentiated antibody producing B lymphocytes.
Present in severely chronic inflammation.
What are giant cells?
Multinucleate cells made by fusion of macrophages
When do giant cells form?
Frustrated phagocytosis - macrophages cannot phagocytose the debris/bacteria and so fuse together to form giant cells
In what type of chronic inflammation are giant cells found?
Granulomatous inflammation
What are the 3 types of giant cells? How are the nuclei arranged in each, and give an example of when they occur
Langhans giant cells - nuclei around periphery of giant cell, necrosis in centre. Eg TB.
Foreign body giant cells - nuclei random. Eg foreign body that is difficult to phagocytose.
Touton giant cells - nuclei in ring towards centre. Eg lesions with high lipid content such as fat necrosis.
Name 4 effects of chronic inflammation
Fibrosis
Impaired function
Atrophy
Stimulation of immune response
How does chronic cholecystitis lead to chronic inflammation and therefore fibrosis?
Repeated obstruction by gallstones, repeated acute inflammation, chronic inflammation, fibrosis
How many layers of the bowel does ulcerative colitis affect? Therefore what are the main symptoms?
Superficial
Diarrhoea, bleeding
How many layers does Crohn’s disease affect? What are the main symptoms?
Transmural (every layer)
Strictures (fibrous narrowing) and fistulae (abnormal connection between two epithelium-lined organs)
What causes cirrhosis?
Chronic inflammation with fibrosis causes disorganisation of architecture and attempted reorganisation, leading to cirrhosis
Name 3 causes of cirrhosis?
Alcohol
Hep B or C infection
Fatty liver disease (causes by excessive alcohol intake, diabetes, obesity)
What is Graves’ disease?
Autoimmune disease, where chronic inflammation leads to increased thyroid function
Where can chronic inflammation lead to atrophy?
Gastric mucosa
What do granulomas arise with?
Persistant low grade antigenic stimulation or hypersensitivity. This can be severe acute inflammation, de novo chronic inflammation, or repeated attacks of acute inflammation
