Chronic Inflammation Flashcards
What is chronic inflammation
Inflammation in which the cell population is especially: lymphocytes, plasma cells and macrophages
Tends to be long term
What does chronic inflammation tend to feature
Tissue or organ damage
Necrosis
Loss of function
Healing and repair (with granulation tissue, scarring and fibrosis)
What could chronic inflammation be due to
Following from ongoing acute inflammation
Arising as primary pathology
What are the clinical presentation of chronic inflammation
Often no specific area which is sore
Malaise (e.g. TB which can affect lung, lymph node, bone, kidney, skin causing a systemic effect)
Weight loss
Loss of function (e.g. autoimmune thyroiditis, a functional gland destruction, Crohn’s disease, a GI tract ulceration and fibrosis causing pain, diarrhoea and gut obstruction and Leprosy which is cutaneous nerve destruction causing loss of sensation)
How does acute inflammation lead to chronic inflammation
It follows on from where there is a large volume of damage and an inability to remove debris. When this fails to resolve the ongoing acute is insult
When chronic inflammation arises as a primary lesion what is seen
No preceding acute phase
Only chronic changes will be seen
What is organisation
An outcome of acute inflammation where granulation tissue is a characteristic which results in healing and repair and can lead to fibrosis and formation of a scar
What is the function of granulation tissue
Patches tissue defects
Replaces dead or necrotic tissue
Contracts and pulls together
What is the mechanism of action of granulation tissue
Capillaries grow into inflammatory mass Plasma proteins access Macrophages from blood and tissue Fibroblasts lay down collagen to repair damaged tissue Collagen replaces inflammatory exudate
What are the products of granulation tissue
Fibrous tissue - scar (small firm blemish on skin)
Fibrosis as a problem - adhesions between loops of bowel following peritonitis
Can progress to chronic inflammation
What cells are involved in primary chronic inflammation
Lymphocytes
Plasma cells
Macrophages
Fibrosis
What is primary chronic inflammation
An autoimmune disease where autoantibodies are directed against own cell and tissue components through autoantigens
It causes damage or destroy organs, tissues, cells and cell components and can result in thyroiditis, rheumatoid disease, pernicious anaemia (chief/parietal cells) and systemic lupus erythematosis (nuclear antigen)
What type of inflammation is common
Granulomatous
What could primary chronic inflammation be due to
Material resistant to digestion (e.g. mycobacteria, Brucella, viruses)
Cell wall resistant to enzymes
Exogenous substances (e.g. sutures, metal and plastic like joint replacements, mineral crystals, glass) which do not provoke an immune response
Endogenous substances (e.g. necrotic tissue, keratin, hair) which cannot be easily phagocytosed
What tissue components are involved in primary chronic inflammation
Granulation tissue
Collagen
What are lymphocytes
Cells which are part of the immune system
Small and round with lots of subtypes and functions
What are the main types of lymphocytes
T cells
B cells
What is the main function of lymphocytes
Immune response
Immune memory
What are plasma cells
Differentiated B cells that assist in antibody production and are intermediate in size
What mechanisms can B cells undertake
Differentiate into plasma cells to produce antibodies
Facilitate an immune response
Act with macrophages for the antigen presenting capacity
Have immune memory
What do T cells do
Produce cytokines
Produce interferons
Damage and kill (lyse) other cells
Destroy antigens
What do cytokines do
Attract and hold macrophages
Activate macrophages
Other cells (e.g. lymphocytes)
Affect permeability
What do interferons do
Antiviral effects
Attract and stimulate other cells
What do NK-cells do
Destroy antigens and cells using chemical mechanisms involving granule proteins
