Lower respiratory tract infection Flashcards
What constitutes the lower respiratory tract?
Anything below the larynx!
What are the predisposing factors to LRTI?
- Loss/suppression of cough reflex
- Ciliary dysfunction e.g. primary ciliary dyskinesia
- Mucus dysfunction e.g. CF
- pulmonary oedema
Immunodeficiency - Macrophage function inhibition e.g. smoking
What are the main fungi that cause LRTIs and who do they infect most?
Immunocomprised
- aspergillus spp
- candida spp
- pneumocytitis jiroveci
What is bronchitis?
Inflammation and oedema of bronchi and trachea
What are the main symptoms of bronchitis?
dry cough, dyspnoea, tachypnoea
What is the main cause of bronchitis?
Viruses e.g. rhinovirus, adenovirus, influenza
Are bacterial causes of acute bronchitis common?
NO - mainly viruses but can be by
- M pneumoniae
- B pertussis
- H influenza
What are the diagnoses and treatment of acute bronchitis?
usually, mild self limiting disease
- supportive treatment
- O2 for co- morbidities
What is the definition for chronic bronchitis?
Sputum producing cough on most days for 3 months of 2 consecutive years (which is not attributable to another cause)
What is the main cause of chronic bronchitis?
Smoking, pollution, allergen - exogenous irritants (not infection)
What is bronchiolitis?
Inflammation and oedema of the bronchioles
Who does bronchiolitis effect the most?
Paeds (2-10 months)
What is the main cause of bronchiolitis?
RSV
How is bronchiolitis diagnosed?
- Chest x-ray
- FBC
- Microbiological analysis (nasopharyngeal aspirate)
What is pneumonia?
Inflammation of the most distal airways (formation of inflammatory exudate i.e. pus)
Name the two anatomical patterns of pneumonia; what do they look like
- Bronchopneumonia - patchy
- Lobar pneumonia - large part or entire lobe
What is the most common cause for lobar pneumonia?
S Pneumoniae
Name the 4 types of pneumonia
- Community acquired pneumonia (CAP)*
- Hospital acquired pneumonia (HAP) (48hrs after admission - diff. organisms to CAP)
- Ventilator acquired pneumonia (48hrs after ventilation/ET intubation)
- Aspirate pneumonia abnormal entry of food/fluid/stomach acid into LRT
What are the main modes of pneumonia acquisition?
- Person-to-person
- Own commensal bacteria
- Environment
- Animals
What are the typical organisms for pneumonia?
S Pneumoniae H Influenzae S Areus Moraxella catarrhalis Klebsiella pneumoniae
What are the major symptoms of pneumonia?
Productive cough (bloody)
RAPID ONSET
(fevers, rigor, pleuretic chest pain etc)
What are the major SIGNS of pneumonia?
Tachycardia, hypotensive, consolidation
What are the atypical bacterial that cause pneumonia?
- Mycoplasma pneumoniae - associated with nephropathy (e.g. Guinean-Barre, peripheral neuropathy)
- legionella pneumonia - water works/AC/showers - fever, D&V, confusion
- Chlamoydophila pneumoniae
- Chlamoydophila psittaci - birds
What patients are affected by primary viral pneumonia?
Patients with pre-existing cardiac/lung disorders - primary = rare
What non-microbiological investigations would you perform for investigating pneumonia?
- Chest X-ray
- Bloods - FBC,U&E,CRP, LFTs
- Obs - BP, pulse, oximetry
What microbiological testing should we conduct?
- Sputum gram stain and culture
- Blood culture
- Legionella urinary antigen
- Pneumococcal urinary antigen
- PCR (e.g. influenza) and serology e.g. chlymydophila sp. mycoplasma pneu
How do we assess pneumonia?
CURB65 (1 point for each!)
C= confusion
U = urea above 7mmol
R= respiratory rate above 30
B= Blood pressure (low)
65 = above 65yrs
How do we prevent LRTIs
Pneumococcal vaccinations (S. pneumoninae)
Flu vaccines
