76R. Pneumonia and TB overview Flashcards
what is the definition of pneumonia
Infection of the lung parenchyma, involving the distal airspaces with inflammatory exudation
what are the 3 ways we classify pneumonia
- morphology
- clinical setting
- organism
Fluid filled airspaces leads to what
consolidation
what so we mean when we say classification on clinical setting?
Community acquired Vs
Hospital acquired
what are the 2 morphological patterns in pneumonia
lobar pneumonia and bronchopneumonia
what is lobar pneumonia - what is it due to and who is it normally in
confluent consolidation
due to streptococcus pneumoniae
usually in healthy young adults
what is bronchopneumonia - what does it look like
Patchy consolidation, varied organisms, often in pre existing disease contexts
what organisms can be the cause of bronchopneumonia
streptococcus pneumonae
haemophilus influenezae
staphylococcus aureus
anaerobes
coliforms (like e.coli)
what are the complications of pneumonia
- fibrous scarring
-empyema
-lung abscess - Bronchiectasis
define TB
Tuberculosis is a bacterial infection (Mycobacterium Tuberculosis) that effects the lungs and is spread through inhaling tiny droplets from coughs or sneezes
describe primary TB
initial exposure and 5 years after.
mainly stays in the lung
gets phagocytosed and brought to lymph nodes at the hilar and then granulomas kill the disease off
describe secondary TB
reactivation or reinfection in someone with some immunity
usually stays localised in the apices of the lung but can spread if not controlled to the airways and blood stream
what are the 2 types of primary TB
Ghon focus and Ghon complex
describe ghon focus
area either upper of lower lobe or lower of upper lobe that has a small area of infection (of TB)
describe Ghon complex
Ghon Focus plus enlarged hilar lymph nodes with granulomas inflammation
name the 2 types of secondary TB
fibrosing and cavitating Apical lesion
Haematogenous Dissemination
describe fibrosing and cavitating apical lesions
upper part of lung (apices) lesions become fibrotic/scarred and get cavities. These cavities harbour bacteria
describe haematogenous dissemination
the spread of secondary TB into the blood
what does haematogenous dissemination lead to
miliary TB
what is Miliary TB
TB infecting foci on other ogans such as Liver and spleen. Looks like tiny dots/millet seeds
what is a hallmark sign of secondary TB
cavities which harbour bacteria in the lungs
what stain is a special staining technique used to identify mycobacteria, such as those causing tuberculosis.
Ziehl -Neelsen
