Pneumonia and Respiratory Tract Infections Flashcards
What are the 3 ways pneumonia can be acquired?
Community
Hospital
Ventilator
Define bronchitis
Inflammation and swelling of the bronchi
Define bronchiolitis
Inflammation and swelling of the bronchioles
Define pneumonia
Inflammation and swelling of the alveoli
In pneumonia how is gas exchange impaired?
Via infiltration of cells or fluid leakage
Why is pneumonia more concerning than bronchitis or bronchiolitis?
It impairs gas exchange (so o2 uptake and co2 removal are impaired)
What is the first immune cell thats recruited in pneumonia?
Neutrophils
What do neutrophils release when they are recruited to the lungs in pneumonia?
Chemokines like IL-8
What does neutrophils releasing chemokines do?
Causes recruitment of other inflammatory cells
What is the name of the specialised resident immune cell that alveoli have?
Alveolar macrophage
What are alveolar macrophages?
Specialised immune cells that reside in the alveoli
How is prolonged pneumonia different to acute pneumonia?
There is a switch from innate to adaptive immune system
Accumulation is now of lymphocytes (mainly t cells) at site of inflammation
What is the main infectious bacteria that causes pneumonia?
Streptococcus pneumoniae
Describe steptococcus pneumoniae
It is gram positive
It is extracellular
It is opportunistic
What antibiotics is strep pneumoniae susceptible to?
Beta lactams
How do beta lactams work?
They bind proteins in the bacterial cell wall and prevent transpeptidation so the bacteria cannot replicate
What is chlamydia pneumoniae resistant to?
Penicliin
How is chlamydia pneumoniae treated?
By using a macrolide that inhibits the 50s ribosomal subunit stopping protein synthesis
What is walking pneumonia?
Atypical bacteria causing a milder pneumonia that is more prolonged in terms of symptoms due to slower replication rates
What are some risk factors for pneumonia development?
Under 2 yrs or over 65 yrs Smoking Alcoholism Poverty Inhaled corticosteroids Immunosuppressants Proton pump inhibitors Medical conditions eg asthma, COPD, heart disease, liver disease, diabetes, HIV, malignancy
What scoring system is used to assess the severity of pneumonia and decide course of treatment?
CRB severity score
What supportive treatment is used for pneumonia if other things aren’t working?
Mechanical ventilation
When are steroids given in viral pneumonia?
When progression is severe, if they are given before when disease is mild immune clearance of the virus will be suppressed
When are anti virals effective in viral pneumonia? Why?
Early as early damage is virus mediated, late damage is immune mediated
