Lower Respiratory Tract Infections 2 Flashcards
what are the main problems associated with LRTIs?
Acute Bronchitis COPD Exacerbations Pneumonia Empyema Lung Abscess Bronchiectasis
What is acute bronchitis?
A viral infection causing inflammation of trachea & main airways
How does bronchiectasis relate to LRTIs?
It dilates the airways making patients more prone to infection
How common/severe is pneumonia?
5-11 per 1000 people
22-42% requires hospitalisation
5.7-12% mortality in the hospitalised patients
Symptoms of Pneumonia?
Malaise Fever Pleuritic Chest Pain (sharp) Cough Purulent (infected) Sputum Dyspnoea Headache
Why is it difficult to diagnose pneumonia?
Its initial symptoms are very vague and fit other LRTIs.
What are the signs of pneumonia?
- Pyrexia
- Tachypnoea
- Central Cyanosis
- Dullness on Percussion of the affected Lobes
- Bronchial Breath Sounds
- Inspiratory Crackles
- Increased Vocal Resonance
How does increased vocal resonance occur in pneumonia?
Consolidation of the lobe leads to increased vocal resonance.
How do we investigate Pneumonia?
Serum Biochem, FBC (Infection)
CRP (shows inflammation)
CXR (shows degree of consolidation)
Blood Culture (picking out specific pathogen in feverish patients)
Sputum Microscopy/Culture (picking out pathogen)
Throat Swab (for Atypical Pathogens e.g. Viruses)
Urinary Legionella Antigen (To check for Legionnaires disease)
What is legionnaires?
A serious lung infection caused by legionella bacteria.
What are the most common causes of Penumonia?
Strep. Pneumoniae (Gram +ve, Pneumococcus) [36%] H. Influenzae [10.2%] Legionella [0.4%] Staph. Aureus [0.8%] Viruses [13.1%] Mycoplasma Pneumoniae [1.3%] Chlamydia Psittaci [1.3%]
Why dont the common causes of pneumonia add up to near 100%?
In the majority of cases the causative microorganism isnt found.
Which pneumonia causing organisms are atypical?
Chlamydia Psittaci
Mycoplasma Pneumoniae
How would strep Pneumoniae appear under gram staining & Microscopy?
Purple
Balls (cocci) forming chains
What scale do we use to score the severity of penumonia?
The CURB 65 scale. Each letter + 65 stands for a criteria. The number they score determines how to respond.
What are the criteria of the CURB 65 scale?
C - Confusion U - Blood Urea>7 R - Respiratory Rate>30 B - Diastolic BP<60 65 - Age>65 yrs
Do we hospitalize a 0 CURB65 score?
Assume low risk and treat in the community
Do we hospitalise a curb65 score of 1-2?
Usually need hospital level treatment
Do we hospitalise a CURB65 score of 3-5?
Assume a high risk of death and admit to ITU
How do we treat a CURB65 score of 0-1?
Amoxycillin or Clarithromycin/Doxycycline