MoD - Chronic Inflammation Flashcards
What is the result of chronic inflammation?
What is the result of acute inflammation?
Repair and scarring
Resolution is possible
How does chronic inflammation arise?
May ‘take over’ from acute inflammation - if damage is too severe to be resolved within a few days
May arise de novo - some autoimmune conditions = RA
Chronic persistent infections - Viral hepatitis
Chronic low level irritation - reaction to foreign material
May develop alongside acute inflammation - in severe repeated or persistent irritation
Prolonged exposure to toxic agents
What does chronic inflammation look like?
Microscopic appearances are much more variable than acute inflammation
Most important characteristic = type of cell present
What types of cell are present in chronic inflammation?
Macrophages Lymphocytes - B (Plasma cell) and T type Eosinophils Fibroblasts/myofibroblasts
What are macrophages derived from?
What are their functions?
Blood monocytes
Phagocytosis and destruction of debris and bacteria
Processing and presentation of antigen to immune system
Synthesis of cytokines, complement components, blood clotting factors and proteases
Control of other cells by cytokine release
Stimulate angiogenesis - formation of new blood vessels
Induce fibrosis
Induce fever
What are the functions of lymphocytes?
What are the the two types and their functions?
Complex, mainly immunological Process antigens Secrete antibodies Secreting cytokines Killing cells
B lymphocytes = produce antibodies
T lymphocytes = control and some cytotoxic functions
What are plasma cells?
Differentiated antibody producing B lymphocytes
When are eosinophils present?
Allergic reactions
Parasite infestations
Some tumours e.g. Lymphomas
What is the function of fibroblasts/myofibroblasts?
Recruited by macrophages to make collagen
What are giant cells
What are the three types?
Where are they found?
Multinucleated cells made by fused macrophages
‘Frustrated phagocytosis’
Langhans - TB
Foreign Body Type - Foreign material
Tout on - Fat necrosis
What are the cell types in..
Rheumatoid arthritis
Chronic gastritis
Leishmaniasis (protozoan infection)
Mainly plasma cells
Mainly lymphocytes
Mainly macrophages
What may the presence of a giant cell type help with?
Help to diagnose
What are four effects of chronic inflammation?
Excessive fibrosis - e.g. Gall bladder, cirrhosis, ulcers
Impaired function - e.g inflammatory bowel diseases (rarely increases function)
Atrophy - gastric mucosa (loose cells that produce gastric acid)
Stimulation of immune response - macrophage, lymphocytes interactions
What is an example of fibrosis?
What happens in this condition?
Chronic Cholecystitis
Repeated obstruction by gall stones.
Gall stones and thickened fibrotic wall
Repeated attacks of acute inflammation –> chronic inflammation
Why would gastic ulceration occur?
What are the two types and what causes them?
Imbalance of acid production and mucosal deference
Acute - alcohol, drugs
Chronic - helicobacter pylori