Respiratory tract infections and immunity Flashcards
What do respiratory infections often display?
Progressive symptomology.
What medications are risk factors for pneumonia?
- Inhaled corticosteroids
- Immunosuppressants (e.g. steroids)
- Proton pump inhibitors
What are the bacterial causes of community acquired pneumonia? (5)
- Streptococcus pneumoniae (40-50%)
- Myxoplasma pneumoniae
- Chlamydia pneumoniae
- Staphylococcus aureus
- Haemophilus Influenzae
What bacteria cause ventilator associated pneumonia?
- Pseudomonas aeruginosa (25%)
- Staphylococcus aureus (20%)
- Enterobacter
What examples of bacteria that cause atypical pneumonia? (3)
- Mycoplasma pneumoniae
- Chlamydia pneumoniae
- Legionella pneumophilia
What mechanisms of damage are there in pneumonia?
- Inflammation and swelling of alveoli
- fluid builds up and cells infiltrate
How do we grade potential bacterial pneumonia?
CRB/CURB-65 scoring (1 point per item)
- Confusion
- Respiratory rate → >30 breaths a min
- Blood pressure → <90 systolic and/or 60 mmHg diastolic
- 65 → 65 years old or older
What do we add to CRB-65 / CURB-65 in a hospital?
Urea → 7 mmol/L
What antibiotics are there for bacterial pneumonia? (2 main types)
- Penicillins - prevent transpeptidation → gram positive
- Macrolides e.g. clarithromycin- bind to the bacterial ribosome to prevent protein synthesis → gram negative
What do opacities on lung X ray mean?
Fluid build up due to bacterial or viral pneumonia
How does respiratory epithelium act as first line of defence against pathogens? (5 ways)
What kind of antibody is common in upper respiratory tract?
IgA,
High frequency of IgA-plasma cells
What kind of antibody is common in lower respiratory tract?
IgG
- Thin walled alveolar space allows transfer of plasma IgGs into alveoli
What is a potential issue with too much IgG?
Too much inflammation and damage in exchange surfaces
What is the leading cause of infant hospitalisation in developed world?
Respiratory syncytial virus (RSV)
