Chronic Inflammation Flashcards
What are the differences between chronic and acute inflammation?
…
What are the cells involved in chronic inflammation?
Macrophages
Lymphocytes
Plasma cells
Fibroblasts
What are the potential causes of chronic inflammation?
Acute inflammation
Primary leison
What are the effects of chronic inflammation?
Increase in cells involved
Organ/tissue necrosis and loss of function
Healing and repair - granulation tissue, scarring and fibrosis
What do fibroblasts do?
Lay down collagen to repair tissue (scar tissue)
Factors that promote healing and repair?
Cleanliness
Good nutrion
Stable metabolism
What is angiogenesis?
Formation of new blood vessels, part of granulation tissue and repair.
Allows blood supply to be re-established in damaged tissue
Factors that impair healing and repair?
Dirty/open wounds
Poor nutrition, lack of vit A and C
Abnormal metabolism
Inhibition of angiogenesis
What does idiopathic mean?
No known cause
What is granulomatous inflammation?
SPecial type of chronic inflammation Presence of granulomas in tissues Have antigens that you CANT digest Many serious infections cause this Include lots of global scale diseases
What is a granuloma?
Aggregate of macrophages Epithelioid Surround dead material Contain neutrophils, eosinophils Response to indigestible antigen
Many are type 4 hypersensitivity responses
What happens if you ingest glass?
Indigestible antigen - no immune response
Granuloma responds
What are giant cells?
Controversy - fusion of macrophages or replicating macrophages (no division)
Often associated with granulomas, granulation tissue - acutely inflamed, neutrophils, pus, organisation
E.g Langhans type giant cell - found in tuberculosis
Silicone associated giant cell
Eg breast implants
Produces foreign body, contains lots of macrophages
Examples of granulomatous diseases
TB
Leprosy
Syphillis
Crumbly white structures on lungs with TB
Granuloma tissue
Leprosy
Granulomatous inflammation on skin (bubbling blisters)
Syphillis
No decrease in cases seen
Penicillin can cure
Huge proportion of sex workers with syphillis
Ulcers on places which make contact with others
What is a ‘chancre’ regarding syphillis?
Blister/ hole type
What are some non-infective granulomas?
Rheumatoid disease - destruction of joints
Crohn’s disease - ulcers in colon, fibrosis of wall
Sacroidosis - pulmonary disease, fibrosis, granulomas forming near airways
Wound healing
Process of repair of tissue damage
Phase of acute inflammation
Local angiogenesis (new vessels grow)
Fibrosis and scar formation
Primary intention healing
Inconspicuous
Minimal granulation tissue
Small scar
Linear scar
Healing by secondary intention
Lots of granulation tissue
Contraction and scarring (ill-defined - not linear)
Sequence of events
Injury, blood clot, acute inflammation, fibrin
Many growth factors, cytokines involved
Granulation tissue growth - angiogenesis
How does diabetes affect healing process?
Scarring made moe difficult
Fracture healing
Same principles as soft tissue healing
Sequence o events in feature healing
Trauma, fracture, haematoma- Lots of blood produced from bone (blood loss)
Bits of dead bone and soft tissue
Acute inflammation, organisation, granulation tissue, macrophages remove debris
Granulation tissue contains OSTEOBLASTS as well as FIBROBLASTS
What is callus?
Osteoblasts laying down tissue (woven bone with nodules of cartilage)
Callus formation is followed by bone remodelling (with lamella bone - stronger, normal bone)
What is stronger - woven or lamellar bone?
Lamella bone
Where does angiogenesis occur?
Thrombosis - limits thrombus propagation, reinstatement of flow
Malignant tumours - occurs as tumour grows
Atherosclerosis - similarities with chronic inflammation
What is atherosclerosis?
Deposition of fat on walls of arteries
