Respiratory Tract Infections Flashcards
How do we divide RTIs?
Upper and lower
What are the URTIs?
o Sinusitis
o Tonsillitis
What are the LRTIs?
- Bronchitis
- Pneumonia
- Empyema
- Bronchiectasis
- Lung abscess
What do we get RTIs?
- 18yo female; fever, cough and malaise
- Diagnosed with flu by GP (no ABx given)
- Attended A&E with…
- T 38C
- 87% sats on room air
- Chest clear, RR 24
- Bloods (WCC 40.8, Neut 36.3, CRP 63)
CXR → double heart border (‘Sail’ sign)
densely consolidated and collapsed lower lobe
- 18yo female; fever, cough and malaise
- Diagnosed with flu by GP (no ABx given)
- Attended A&E with…
- T 38C
- 87% sats on room air
- Chest clear, RR 24
- Bloods (WCC 40.8, Neut 36.3, CRP 63)
What is the most likely organism?
Streptococcus pneumoniae
What is happening?
- Alpha-haemolytic and optochin-sensitive
- Gram-positive cocci (chains and pairs)
What percentage of.community-acquired pneumonia is strep. pneumoniae responsible for?
30-50%
What does acute onset of strep. pneumonia cause?
- Severe pneumonia
- Fever and rigors
- Lobar consolidation
What is strep pneumonia almost always sensitive to?
- Almost always penicillin-sensitive
- Penicillin-resistance strains may be imported from Southern Europe
Define pneumonia.
inflammation of the lung alveoli
What is the mortality of pneumonia?
Patients are sick with a mortality of 5-10%
20-40% admitted to hospital
How does pneumonia present?
- Fever
- Cough
- Abnormal CXR
- Pleuritic chest pain
- SoB
How do we classify pneumonia?
- Community-acquired
- Hospital-acquired/nosocomial (i.e. ventilator-associated)
What are the underlying factors behind pneumonia that need to be considered?
- Pre-existing lung disease
- Immunocompromise
- Geography, seasons, epidemics
- Travel, exposure to animals
Why is no microbiological ID made in most cases of CAP?
this is often due to difficulty obtaining a good sputum sample and because of early treatment with antibiotics
What are the main organisms causing CAP?
- Streptococcus pneumoniae
- Haemophilus influenzae
- Moraxella catarrhalis
- Staphylococcus aureus
- Klebsiella pneumoniae
How do pathogens causing CAP differ by age?
What are the causative organisms of CAP?
- TYPICAL (85%)
- Streptococcus pneumoniae
- Haemophilus influenzae
- ATYPICAL (15%)
- Legionella
- Mycoplasma
- Coxiella burnetii (Q fever) from exposure to farm animals
- Hepatitis
- Chlamydia psittaci (Psittacosis) from exposure to birds
- Splenomegaly, rash, haemolytic anaemia
What are the symptoms of CAP?
- SoB
- Cough ± sputum
- Fever
- Rigors
- Pleuritic chest pain
- Malaise, N&V
What are the signs of CAP?
- Pyrexia
- Tachycardia
- Tachypnoea
- Cyanosis
- Bronchial breathing
- Crackles
- Dullness to percussion/tactile vocal fremitus
What investigations should be done on CAPs?
- FBC, U&E, CRP
- BCs, Sputum MC&S
- ABGs
- CXR
What scoring system do we use to assess severity of CAP?
- Confusion
- Urea > 7 mmol/L
- RR > 30
- BP < 90 systolic, < 60 diastolic
- 65+ years
2 = consider admitting
2-5 = manage as severe / consider ITU
Define bronchitis.
inflammation of medium-sized airways
Who is bronchitis usually seen in?
Smokers
How does bronchitis present?
- Cough
- Fever
- Increased sputum production
- Increased shortness of breath
What does a CXR usually show for bronchitis?
Normal
What organisms cause bronchitis?
- Viruses
- Streptococcus pneumoniae
- Haemophilus influenzae
- Moraxella catarrhalis
What is the tx for bronchitis?
- Bronchodilation
- Physiotherapy
- Antibiotics
- 56yo man; flu-like illness
- Presented with cough, fever, haemoptysis, pyrexia (but not severely unwell)
- What organism would you suspect?
- Strep pneumonia
- H. influenzae
- Staph aureus
- Klebsiella
Cavitation on X ray
H. influenzae