chronic inflammation Flashcards
inflammation definition
it’s a defensive process against local tissue damage. It involves a complex reaction of blood vessels, plasma components, blood cells, and connective tissue
causes of chronic inflammation
- persistence of infection
- prolonged exposure to insult
- auto-immunity
how long can chronic inflammation last?
from a few months up to tens of years
what characterizes the course of chronic inflammation?
alternating exacerbations and remissions
which cells are present in the focus of chronic inflammation?
mononuclear cells such as lymphocytes, plasmocytes, and macrophages. Neutrophils are added during exacerbations.
what type of inflammation occurs during chronic inflammation?
productive inflammation, with an exudative reaction added during exacerbations
what is essential in chronic inflammation?
the presence of fibrosis
which cells play a role in chronic inflammation?
lymphocytes, macrophages, plasma cells, eosinophils, mast cells
what are the morphological features of chronic inflammation?
infiltration, tissue destruction, healing
which cells are involved in the chronic inflammatory response?
lymphocytes, macrophages, and plasma cells
What can macrophages transform into during chronic inflammation?
Epithelioid cells and multinucleated giant cells.
general features of chronic inflammatory response
necrosis and attempts and healing
necrosis in chronic inflammation
due to cell death in the lesion’s center caused by micro-organisms, endarteritis, and delayed hypersensitivity.
What are the attempts at healing in chronic inflammation?
Proliferation of endothelial cells to form blood and lymphatic channels, proliferation of fibroblasts, collagen formation, and accumulation of lymphocytes and plasma cells.
Healing after Chronic Inflammation:
- Replacement of functioning tissue by fibrous tissue (fibrosis)
- Adhesions in serosal cavities
- Stricture formation (can obstruct normal flow within passage because of the scar tissue)
what is granulomatous inflammation?
an infection that develops when phagocytosis is persistently stimulated
what causes granulomatous inflammation?
it develops due to the presence of inherently indigestible material, persistent infection, or chronic stimulation of macrophages
what are the main cells involved in granulomatous inflammation?
epithelioid macrophages
what can epithelioid macrophages fuse to become?
syncytial multinucleated giant cells, such as langerhans giant cells and foreign body giant cells
how are granulomas further subdivided?
according to whether they show necrosis: necrotizing granulomas (TB) and nonnecrotizing granulomas (sarcoidosis)
what are the 4 components of granulomatous inflammation?
fibroblasts, lymphocytes, histiocytes, and giant cells
what bacterium causes tuberculosis?
Tuberculosis is caused by the tubercle bacillus, usually the hominis strain, but can also be caused by bovis and various atypical mycobacteria.
What occurs in the first stage of tuberculosis infection?
The first infection leads to a transient acute inflammatory reaction.
What characterizes the early tubercle granuloma in the lung during tuberculosis?
The early tubercle granuloma in the lung contains giant cells, epithelioid cells, lymphocytes, and peripheral fibroblasts.
What is a Ghon focus?
A Ghon focus is the formation of several granulomas in the lung during tuberculosis.
What is a Ghon complex?
A Ghon complex consists of a subpleural focus in the lung and the development of granulomas in regional lymph nodes.
What are the three possible courses of tuberculosis after the development of delayed hypersensitivity?
- Healing by fibrosis
- Progression to a chronic form
- Disseminated tuberculous granulomas throughout the body (miliary spread)
What can chronic tuberculosis lead to?
- Healing, leaving a scar
- Progression, which may lead to bronchial erosion, cavitation, bronchopneumonia, or miliary spread
What bacterium causes syphilis?
Syphilis is caused by the spirochaete Treponema pallidum.
What happens during primary syphilis?
- Initial infection and multiplication at the site of entry.
- Spirochaetes enter regional lymph nodes.
- Spirochaetes enter many tissues, multiply, disseminate, and sensitize tissues.
- A primary sore or chancre forms at the site of entry within 2-4 weeks of initial infection.
What are the clinical features of secondary syphilis?
- Low-grade pyrexia
- Lymphadenopathy
- Skin rashes
- Snail track ulcers
What characterizes tertiary syphilis?
- Gummata - localized lesions most common in the hard palate, liver, and testis.
- Diffuse lesions occur in the cardiovascular system, nervous system, and skeletal system.
