Bacterial RT Infections Flashcards
What is the mortality rate of bacterial RT infections?
8-14%
30% in ICU
Who most commonly gets bacterial RT infections?
Extremes of age
What is the pathogenesis of bacterial RT infections?
- Pathogens overcome the immune system due to:
- Large innoculum
- Increased virulence
- Host defense defect
What are the typical pathogens which cause bacterial RT infections?
- Moraxella catharralis
- Haeophilus influenzae
- Streptococcus pneumoniae
What are the atypical pathogens which cause bacterial RT infections?
- Legionella. pneumoniae
- Chlamydia. pnaeumoniae
- Mycoplasma. pneumoniae
What is the number one cause of community acquired pneumonia?
S. Pneumoniae
What are the risk factors for S. Pneumoniae?
- Cancer
- Asthma
- Alcohol
- Smoking
Describe the clinical symptoms of s. pneumniae?
- Abrupt Onset
- Cough
- Fever
- Pleuritic chest pain
What is pictured here?
Chest XR of someone with S. pnuemoniae RT infection
What clinical findings would be present with s. pneumoniae infection?
- Dull percussions
- Coarse crepitations
- Increased vocal resonance
Describe resistance of s. pneumoniae to penicillin?
- Asia
- North America
- Southern Europe
What can S. Pneumoniae be treated with if the patient has a penicilin allergy?
- Macrolides
- Clarithromycin
- Tetracyclines
- Doxycycline
When is a person most likely to become infection with Haemophilus influenzae?
- Older people
- Underlying lung disease
Describe the clinical presentation of H. influence respiratory tract infection?
- Abrupt onset
- Cough
- Fever
- Pleuritic chest pain
Describe the clinical findings of H. influenzae respiratory tract infection?
- Dull percussions
- Coarse crepitations
- Increased vocal resonance
What is the first line treatment for H. influenzae respiratory tract infections?
Amoxicillin
What should someone with H. influenzae be treated with if there was a risk of beta lactamase?
- Co-amoxiclav
- Macrolides (clarithromycin)
- Tetracyclines (doxycicline)
Describe mycoplasma pneumoniae?
- Smallest free living bacterium
- Lack of cell wall
- Difficult to grow
Describe the spread of mycoplasma pneumoniae?
- Droplet spread (sneezing)
- Seasonal incidence
- Autumn
- Winter
How is M. pneumoniae diagnosed?
- Serology
- PCR
- sputum
- throat swab
How is L. pneumophila diagnosed?
- Culture
- Serology
- Urinary antigen test
How should L. pneumophila be treated?
- Macrolides (clarithromycin)
- Quinolones (ciprofloxacin)
- Tetracyclines (doxycicline)
What is it important to cover with a history in someone with pneumoniae?
- Symptoms
- Past medical history
- Epidemiology
- travel
- ill contacts
- water exposure
Name the categories of investigations into patients with pneumoniae?
- Blood tests
- Imaging
- Microbiology
What blood tests should be performed on someone with pneumonia?
- FBC
- U&Es
- ABGs
What microbiology tests should be performed on someone with pneumonia?
- Blood cultures
- Sputum culture
- Throat swab
- Urine legionella antigen
What imaging should be performed on someone with pneumonia?
- CXR
- ECG
How would someone with pneumonia be managed?
- Airway, breathing, circulation
- Antibiotics?
- Admission to hospital?
- CURB65
- Sepsis?
- Hypoxia?
What is important about H. influenza?
The general population are vaccinated against it (Hib)
What does Hib cause?
Epiglottitis
Which H. Influenza strains cause pneumonia?
- All of them apart from Hib
- (vaccine does not protect against pneumonia)
Where does H. Influenza colonise?
What does this mean for what it infects?
Colonises the upper RT
Causes infections around about this area
Name some infections which H. Influenza can cause due to colonised the upper RT?
- Sinusitis
- Pneumonia
- Otitis media
- Conjuctivitis
How will people present with M. pneumonia?
- Tired
- Fever
- Headache
What is an atypical pneumonia?
- Very non-specific presentation
- Chest x-ray will show lung consildation
Name some complications of M. pneumonia?
- Guillain-Barre
- Reactive arthritis
- Haemolysis (cold)
How can you be infected by legionella pneumophilia?
What is a major factor which helps diagnose legionella?
- Contaminated water systems
- Soil and compost
Complete patient history
Describe the presentation of legionella pneumophilia?
- Atypical presentation
- Headache
- Tiredness
- Fever
Describe the CURB65 scoring system?
- C - Confusion
- U - Urea > 7
- R - RR >= 30
- B - BP, diastolic <60 or systolic <90
- 65 - Age over 65 years old
Severe pneumonia if they have score >2
What defines severe pneumonia regardless of CURB65 score?
- Multilobar consolidation on CXR
- and/or
- Hypoxia on room air
Describe the qSOFA criteria for sepsis?
- Altered mental status
- Systolic BP < 100 mmHg
- RR > 22 breaths/min
What clinical assessments can be used with a patient who has pneumonia?
- CURB65 score
- Sepsis qSOFA
- Multilobar consolidation on CXR/Hypoxia on room air
