What are the common microorganisms found in the respiratory tract?
- Viridans streptococci
- Neisseria spp
- Candida spp
What are the less common microorganisms found in the respiratory tract?
- Streptococcus pneumonia
- Streptococcus pyogenes
- Haemophillus influenza
What natural defences does the respiratory tract have to protect against infection?
- Cough and sneezing reflex
- Muco-ciliary clearance mechanisms
- Respiratory mucosal immune system
What are the muco-ciliary clearance mechanisms?
- Ciliated columnar epithelium
- Nasal hairs
What are the components of the respiratory mucosal immune system?
- Lymphoid follicles of the pharynx and tonsils
- Alveolar macrophages
- Secretory IgA and IgG
What are the main upper respiratory tract infections?
- Rhinitis (common cold)
- Ottitis media
What is otitis media?
Inflammation of the middle/inner ear
What are URTs most commonly caused by?
What viruses commonly cause URT infections?
- Respiratory syncytial virus (RSV)
Other than virally, what else can cause URTs?
What is bacterial super-infection common with?
- Otitis media
What can URTs caused by bacterial super-infection lead to?
- Brain abscess
What is pneumonia?
General term denoting inflammation of gas-exchanging region of the lung
What is pneumonia usually due to?
Infection, bacterial or viral
What is pneumonia an infection of?
The lung parenchyma
What is pneumonitis?
Inflammation of the gas-exchanging region of the lung due to causes other than infection, such as physical or chemical damage
What is lobar pneumonia?
Pneumonia localised to a particular lobe(s) of the lung
What is lobar pneumonia most often due to?
What is bronchopneumonia?
Pneumonia that is diffuse and patchy
What path does infection take in bronchopneumonia?
It starts in the airways, and spreads to adjacent alveoli and lung tissue
What causes bronchopneumonia?
- Streptococcus pneumoniae
- Haemophilus influenza
- Staphylococcus aureus
What is aspiration pneumonia?
Aspiration of food, drink, saliva, or vomit that leads to pneumonia
Who is more likely to develop aspiration pneumonia?
- Individuals with altered levels of consciousness
- Individuals with problems swallowing
Why may individuals have an altered level of consciousness?
- Drug or alcohol abuse
Why may an individual have problems swallowing?
Nerve or oesophageal damage
What organisms are involved in aspiration pneumonia?
- Oral flora
What is interstital pnuemonia?
Inflammation of the intersticium of the lung
What becomes inflamed in interstitial pneumonia?
- Alveolar epithelium
- Pulmonary capillary endothelium
- Basement membrane
- Perivascular and perilymphatic tissues
What is chronic pneumonia?
Inflammation of the lungs that persists for an extended period of time
What common bacteria cause pneumonia?
- Haemophilus influenzae
- Klebsiella pneumoniae