Lower Respiratory Tract Infections Flashcards
What does the lower respiratory tract contain?
Trachea, primary bronchi and lungs
What are the main causes of respiratory tract infections?
Bacteria
Viruses
Fungi
Protozoa
What are the 2 main types of pneumonia?
Community acquired pneumonia
Hospital Acquired pneumonia
What are the features of community acquired pneumonia?
Mainly in young and old
many cases idiopathic
gram negative
secondary to another RT infection
What are the symptoms of pneumonia?
sudden onset of chills, followed by fever/chest pain/productive cough
raised WBC count
thick sputum, rusty colour, purulent
How do you treat pneumonia?
Community acquired - beta lactam agent and macrolide
CURB score assessment - 5 point score (confusion, urea high, high resp rate, low blood pressure) and if more than 3 high death risk
What is atypical pneumonia?
not due to strep pneumonia
doesn’t respond to beta lactam
insidious onset, normal CXR, subclinical infection
Which forms of pneumonia are typical and which are atypical?
Typical - S. pneumoniae, H.influenza, group A strep
Atypical - C pneumoniae, L pneumophilia, M.tuberculosis, Myocplasma
What is streptococcus pneumoniae?
Typical more and more prevalent AKA pneumococcus colonises upper respiratory tract identifiable features: gram stain of sputum negative alpha haemolytic, bile soluble sputum
What is mycoplasma pneumoniae?
atypical droplet transmission neurological diagnosis - CXR patchy bilateral bronchopneumonia difficult to culture antibodies produced against patients own RBCs IgM test serology PCR
What is legionella penumophilia?
atypical small gram negative bacteria distinctive orange/yellow slow growth clinical signs - confusion, muscle ache, pneumonia, renal failure
What is chlamydia pneumoniae?
person to person spread
atypical
co-pathogen in coronary artery disease
What is pneumocystis pneumonia?
important cause of pneumonia in severely immunocompromised
How is pneumonia diagnosed?
history and clinical exam
chest x ray, blood count, blood cultures
sputum
What are some pneumonia complications?
pleural effusion
emphysema
lung abscess
What is fever?
caused by coxiella burnetiid
transmitted through infected animals
causes atypical pneumona
What is tuberculosis?
chronic
respiratory but can affect any organ almost
primary infection = may inhale infected droplets from cough or sneeze
mycobacteria caused - aerobic, non-motile, straight/curved, fatty acid cell wall
What is clinically important about TB mycobacteria?
Resistant to drying, antibiotics, alcohol and alkalis, hydrophobic, impermeable to standard stains
What are some common LRTIs?
bronchitis
bronchiolitis
pneumonia
influenza
What are some symptoms of acute bronchitis?
sore throat, fatigue, stuffy/runny nose, fever, body aches, vomiting, diarrhea
How is acute bronchitis managed?
educate about lack of antibiotic use
encourage fluid intake and humidity
recommend analgesics, antitussives and antipyretics
Define pneumonia
Inflammation of the alveoli in either one or both lungs
Alveoli become inflamed & fill up with fluid
Common pathogen: Bacteria or virus
Elderly & the very young: Greatest risk
What are the symptoms of pneumonia?
headache, fever, weakness, dry cough, nasal congestion, chills, sore throat, sweating, muscle aches
What is the pathophysiology of pneumonia?
injury-> inflammation -> innate immunity -> alveolar injury
How is pneumonia diagnosed?
sputum culture urine test PCR CT scan complete blood count
How is pneumonia prevented?
- improve indoor air quality
- drink safe water, good sanitation, frequent hand washing with soap
- good nutrition
- recognise danger signs and seek help quickly
- routine immunisations (pertussis, measles)
- exclusive breastfeeding for first 6 months
How is pneumonia treated?
home care advice
oral amoxicillin
first dose antibiotic and referral to facility for injectable antibiotic
supportive therapy
