GEP (Life Protection) Week 5 Flashcards
What are the 4 types of chronic inflammation?
- Non-specific
- Autoimmune
- Chronic suppurative
- Chronic granulomatous
Define chronic inflammation?
This is where inflammation persists for weeks, months or longer. It may occur from acute inflammation or from the outset. It is more likely to cause tissue destruction and heal with irreversible scarring rather than regeneration.
3 process occurs simultaneously
-Persistent tissue injury and destruction
-Ongoing inflammatory response to limit the damage
-Attempts to organise and heal by fibrosis (scarring)
Describe the different response of the innate and adaptive immune response to inflammation?
What is a granuloma?
This is an aggregate of activated (epithelioid) macrophages, which have formed when a causeative agent cannot be removed. This granuloma is formed by a ring of macrophage, TH1 cell and others walling the site of inflammation to stop the spread.
Composition of granuloma:
-Macrophages
-Lymphocytes: mainly T-cells & some B-cells
-Fibroblasts, connective tissue (collagen)
-Necrotic tissue
How many types of hypersensitivity is there?
There are 5 types of hypersensitivity
Describe the different types of hypersensitivity (1,2,3,4)
Describe the different types of hypersensitivity (1,2,3,4) continued.
Describe type 5 hypersensitivity?
Type 5 hypersensitivity is technically classified as type 2 but given different calssification because of their antigen-mediated stimulatory/inhibitory effect.
Except 2 exceptions:
graves and myasthenia gravis are type 2 hypersensitivity.
What is the definition and aetiology of Tuberculosis?
-TB is the infection of mycobacterium tuberculosis.
-It is spread by inhalation of infectious droplets released when coughing
-There needs to be a prolonged contact for transmission.
-Aerobic rod-shaped bacilli, with a high oxygen demand, so usually infect the upper lobes of the lung
-‘Acid fast’ when using the Ziehl-Neelsen stain.
Mycobacteria are called acid-fast bacilli because they are rod-shaped bacteria (bacilli) that can be seen under the microscope following a staining procedure in which the bacteria retain the color of the stain after an acid wash (acid-fast).
Brief Epidemiology of TB
-1 of the Top 10 causes of death worldwide
-1.7-2 billion people have latent TB worldwide.
-Significant mortality from co-infection with HIV
-40% of UK cases occur in London.
Describe the pathophysiology of TB?
What is a ghon focus
It is a small focus of granulomatous inflammation, which may become visible on a chest X-ray if it grows large enough or if it calcifies. A Ghon focus usually heals without further trouble, but in some patients tuberculosis spreads from it via the lymphatics, the air spaces, or the bloodstream.
What is a ghon complex
A ghon complex= ghon focus + ipsilateral mediastinal lymph nodes
Describe the natural history of TB infection
What are the clinical signs and differential for TB
Differentials
-Lung cancer
-COVID
-Pneumonia
-Sarcoidosis
-Lymphoma
-Other!
What are the extrapulmonary manifestations?
-CNS - TB meningitis (headache, neck stiffness, vomiting), reduced consciousness, focal neurological signs)
-Lymph node TB - enlarged, firm, non-tender cervical lymph nodes
-Genitourinary TB
-Pericardial TB - pericardial effusion, constrictive pericarditis
-Bone - Pott’s disease, spinal pain, often localised
-GI - mostly affects ileocecal region, causes abdo pain, bloating and obstruction