chronic inflammation Flashcards
(35 cards)
what is chronic inflammation associated with?
greater tissue destruction
what is inflammatory infiltrate in chronic inflammation?
mixture of macrophages and B cells/Tcells
what is the time period for chronic inflammation?
persistent- occurs over months, years an possibly forever
what are the three main classes of chronic inflammation?
- non-specific chronic
- specific (primary) chronic
- chronic granulomatous
what is non-specific chronic inflammation?
Failure to resolve acute inflammation
Persistent bouts of acute inflammation
Excessive suppuration
what is specific chronic inflammation?
Arises de novo
Persistent exposure to agent
what is chronic granulomatous inflammation?
subset of specific chronic inflammation
what is an example of acute inflammation progressing into chronic inflammation?
gingivitis to periodontitis
what type of chronic inflammation do autoimmune diseases come under?
specific
when does chronic inflammation normally arise?
from acute inflammatory disease when the immune system not sufficient to eradicate stimulus
what is the infiltrate in non-specific chronic inflammation?
tissue macrophages, T cells and B cells
what is non- specific chronic inflammation characterised by?
a dynamic balance between tissue destruction and repair
what are the subcategories within specific chronic inflammation?
non-granulomatous or granulomatous
what is specific chronic inflammation characterised by?
excessively activated macrophages
non-immunological specific chronic inflammation induced by?
- foreign body reactions
- inert noxious material eg silica
immunological specific chronic inflammation induced by?
Infective organisms that grow in cells
Hypersensitivity reactions
Autoimmune reactions
Infection by fungi, protozoa or parasites
what is an autoimmune diease?
- Examples of specific chronic inflammation
- Unwanted response to body’s own cells and tissues or commensal bacteria
- Loss of tolerance to self antigens or commensal bacteria
- Multiple mechanisms of tolerance usually prevent autoimmunity
- Recall the positive and negative selection
- Sustained immune response (chronic inflammation) generates cells and molecules that destroy tissues
rheumatoid arthritis
production of PAD and protease enzymes which drive peptide citrullination leading to loss of tolerance
what are the predominant cell types in chronic granulomatous inflammation?
modified activated macrophages (epitheloid macrophages)
- giant cells
- B and T cells
what are the immunological causes of chronic granulomatous inflammation?
delayed hypersensitivity type reaction or invading pathogens
what are the non-immunological causes of chronic granulomatous inflammation?
foreign body in tissue
what are the ways in which macrophages cause tissue injury?
Toxic oxygen metabolites
Proteases
Neutrophil chemotactic factors
Coagulation factors
AA metabolites
Nitric oxide
what are the ways in which macrophages cause tissue repair?
Process of fibrosis
Growth factors
(PDGF,FGF,TGF beta)
Fibrogenic cytokines
Angiogenesis factors (FGF)
Remodelling collagenases
what is orofacial granulomatosis?
- an example of chronic granulomatous inflammation
- granulomas in soft tissue of oral cavity
- if intestinal crohns it is termed oral crohns
- no intestinal crohns- termed orofacial granulomatosis
