Session 3 Flashcards
What is chronic inflammation?
A chronic response to injury with associated fibrosis.
What is the only tissue outcome of chronic inflammation?
Repair and scarring.
How does chronic inflammation arise?
Can take over from acute inflammation if damage is too severe.
Can arise initially eg autoimmune conditions and chronic infections.
Can develop alongside acute inflammation in severe or repeated irritation.
What cells are present in chronic inflammation?
Macrophages, Lymphocytes, plasma cells, Eosinophils and fibroblasts/myofibroblasts.
What are the functions of macrophages?
Phagocytosis.
Presentation of antigen to immune system.
Synthesis of cytokines, blood clotting factors and proteases.
Control of other cells by cytokines release.
Name the 2 types of lymphocytes.
Extra point - what is their function?
B lymphocytes and T lymphocytes.
Extra point - B differentiate to produce antibodies. T are involved in control and cytotoxic functions.
What is the function of plasma cells?
They are differentiated antibody producing B lymphocytes.
When are eosinophils present?
In allergic reactions, parasite infections and some tumours.
What is the function of fibroblasts and myofibroblasts?
They make collagen and are recruited by macrophages.
What we giant cells and why do they occur?
They are multinucleate cells made by fusion of macrophages. They occur due to frustrated phagocytosis.
What are the 3 types of giant cells?
Langhans (TB) foreign body type and touton (fat necrosis)
What do langhans type giant cells look like under the microscope?
Nuclei form large circle with plasma in the centre.
What do touton giant cells look like under the microscope?
A smaller circle formed of the nuclei with plasma in the centre.
What is the main cell type in rheumatoid arthritis?
Plasma cells.
What are the main effects of chronic infection?
Fibrosis - eg gall bladder, chronic cholecystitis.
Impaired function - eg chronic inflammatory bowel disease, rarely get increased function eg Graves’ disease.
Atrophy - eg gastric mucosa.
Stimulation of immune response - macrophage/lymphocyte interactions.
Briefly explain the pathology of chronic cholecystitis.
There is repeated obstruction of the gall bladder by gall stones.
This leads to repeated acute inflammation leading to chronic inflammation.
Fibrosis of the gall bladder wall occurs.
Briefly explain the pathology of inflammatory bowel disease.
It is an idiopathic inflammatory disease that effects the large and small bowel.
Patients have diarrhoea and rectal bleeding.
Eg Crohn’s disease.
Briefly explain the pathology of rheumatoid arthritis.
It is an autoimmune disease with a local and systemic immune response. Localised chronic inflammation leads to the destruction of joints and systemic immune response can effect other organs and can cause proteins to become insoluble.
What is granulomatous inflammation?
Chronic inflammation with granulomas.
What cells make a granuloma?
Lymphocytes and modified immobilised macrophages.
When do granulomas arise?
With persistent, low grade antigenic stimulation.
Hypersensitivity.
What are the main causes of granulomatous inflammation.
Irritant foreign material
Infections eg mycobacteria - TB
Crohn’s disease.
What does a granuloma look like in TB?
It is a langerhans type giant cell with caseous necrosis.
What are the outcomes of cellular TB?
Arrest, fibrosis, scarring
Erosion into bronchus
TB empyema
Erosion into the blood stream
