Chronic Inflammation 1 Flashcards
What is the definition of chronic inflammation?
Inflammation in which cell population is especially
lymphocytes
Plasma cells
Macrophages
Features tissue or organ damage, necrosis, loss of function
Healing and repair: Granulation tissue, scarring and fibrosis
May follow from acute inflammation
Also arises as primary pathology
Tends to be long term
What are the clinical presentations of chronic inflammation?
No specific sore bit
Malaise and weight loss - tuberculosis - system effect
Loss of function - autoimmune thyroiditis (functional gland destruction) -hypothyroidism
Crohn’s disease (GI tract ulceration and fibrosis) - pain, diarrhoea, gut obstruction
Leprosy (cutaneous nerve destruction) - loss of sensation
When do we see chronic inflammation?
Arising from acute inflammation - large volume of damage, poor removal of debris, failure to resolve
rising from a primary lesion
What is characteristic or organisation in acute inflammation?
Granulation tissue - healing and repair, leads to fibrosis and formation of a scar
What is the granulation tissue mechanism?
Capillaries grow into an inflammatory mass
Access of plasma proteins
Macrophages from blood and tissue
Fibroblasts lay down collagen to repair damaged tissue
Collagen replaces inflammatory exudate
What is the function of granulation?
Patches tissue defects
Replaces dead or necrotic tissue
Contracts and pulls together
What are the products of granulation tissue?
Fibrous tissue - scar
Fibrosis as a problem (adhesion between loops of bowel following peritonitis)
Can progress to chronic inflammation
What is the most likely cause of primary chronic inflammation?
Autoimmune disease
How does Autoimmune disease result in chronic inflammation?
Autoantibodies directed against own cell and tissue components - autoantigens
They damage or destroy organs, tissues, cells, cel components
What types of cells does primary chronic inflammation use?
lymphocytes, plasma cells, macrophages, fibrosis
What are the other common methods of triggering a chronic inflammatory response?
Material resistant to digestion : mycobacteria, Brucella, viruses, this is because their cell wall is resistant to enzymes
Exogenous substances:
sutures, metal and plastic eg joint replacements, mineral crystals, glass
Endogenous substances: Necrotic tissue, keratin, hair, none of which can easily be phagocytosed
Granulomatous inflammation is common
What are lymphocytes responsible for?
B cells and T cells
Immune response
Immune memory
What is a plasma cell?
Differentiated B cells, differentiated to produce antibodies
What are the B cell mechanisms?
Antibody production by plasma cels
Facilitate the immune response
Act with macrophages - present antigens
Immune memory
What are the T cell mechanisms?
Produce cytokines - attract and hold macrophages, also activate them
Attract and activate other lymphocytes and immune cells
Alter permeability
Produce Interferons - Antiviral effects, attract and stimulate other cells
Damage and lyse other cells and destroy antigen - chemical mechanisms, granule proteins