Chronic Inflammation Flashcards
What is chronic inflammation?
A chronic response to injury with associated fibrosis. It overlaps with host immunity and, unlike acute inflammation, it’s heterogenous, not stereotyped and less is known about it.
How does chronic inflammation arise?
It could be from an acute insult and resulting inflammation which is severe, so turns into chronic inflammation (if resolution not possible), or chronic insult causing inflammation and scarring.
It arises if the change is too severe to be resolved quickly, or De Novo (autoimmune/chronic infections/chronic ‘low level’ irritation), or develops alongside acute inflammation (in severe persistent/repeated irritation).
Chronic inflammation is characterised most importantly by the type of cells present, how does this compare to acute inflammation?
In chronic inflammation, fewer neutrophils and more macrophages and lymphocytes are seen than in acute inflammation. There is much more of a variable appearance in the former.
Macrophages:
Derived from blood _________, important in acute and chronic inflammation with various levels of ________. Functions: phagocytosis, _____________ and ___________ antigens to the immune system and synthesis of ___________ proteins, blood _________ factors and proteases, control of other cells by ________ release.
Monocytes Activity Processing Presenting Complement Clotting Cytokine
Lymphocytes aka ‘chronic inflammatory cells’, have what function?
Complex, mainly immunological - B cells differentiate to produce antibodies and mature in the bone marrow and T cells are involved in control and some cytotoxic functions. Plasma cells are differentiated, antibody producing B cells, presence of which usually implies considerable chronicity.
How do the cells of chronic inflammation appear microscopically?
Macrophages are large with a bean shaped nucleus.
Lymphocytes have a large nucleus with little cytoplasm.
Plasma cells have an open nucleus wi clumps of chromatin seen around the periphery.
Eosinophils stain bright pink and have a belonged nucleus.
When are eosinophils seen?
After allergic reactions, parasite infestations (polymorphism from bacteria and lymphocytes for viruses) and in some tumours.
Fibroblasts and myofibroblasts make collagen and are recruited by what?
Macrophages.
What are Giant cells?
Multinucleate cells made by fusion of macrophages in frustrated phagocytosis (to help them cope).
Many types of Giant cell are recognised and the type may help with diagnosis, name three and describe when they are seen?
Langhans - tuberculosis (horseshoe of nuclei around periphery).
Foreign body type (multiple irregular aggregates of nuclei - more disorganised).
Touton - present in fat necrosis (organised central part of cell with foamy cytoplasm).
Name 4 effects of chronic inflammation and give examples of where these may occur.
Impaired function e.g. Chronic inflammatory bowel disease, rarely increased function as with mucus secretion.
Fibrosis e.g. Gall bladder - chronic cholecystitis, chronic peptic ulcers, cirrhosis.
Atrophy (reduction in tissue size) e.g. Gastric mucosa, adrenal glands.
Stimulation of immune response with macrophage-lymphocyte interactions.
What is chronic Cholecysitis?
Inflammation of the gall bladder - tall stones, fibrotic wall, repeated attacks of acute inflammation lead to chronic inflammation (repeated obstruction ).
What is Inflammatory bowel disease?
Idiopathic inflammatory disease affecting the large and small bowel. Patients present with diarrhoea, rectal bleeding and other symptoms. The two main types are Crohn’s disease and ulcerative colitis.
What’s the difference between Crohn’s disease and Ulcerative Colitis?
UC is superficial with symptoms of IBD, whereas Crohn’s disease is transmural, leading to strictures and fistulae.
List some common causes of cirrhosis.
Alcohol, infection with HBV, HCV, immunological, fatty liver disease, drugs and toxins.
