Respiratory Tract Infections Flashcards
Name three main groups of respiratory tract infections
Upper respiratory tract infections
Bronchitis
Pneumonia
What anatomy is affected in upper respiratory tract infections?
pharynx, larynx, trachea
Which are mainly caused by bacteria / viruses?
- Upper respiratory tract infections
- Bronchitis
- Pneumonia
Upper respiratory tract infections
- viral
- if bacterial - may be quinsy, acute sinusitis
Bronchitis
- viral (90%)
Pneumonia
- bacterial
What treatment is recommended for viral upper respiratory tract infections?
No specific treatment. Rest
Which upper respiratory tract infections are more serious?
Bacterial ones, eg quinsy, acute sinusitis
What is quinsy?
upper respiratory tract infection
caused by bacteria
a peritonsillar abcess
follows tonsillitis
What are symptoms of quinsy?
unilateral sore throat
painful to swallow (odynophagia)
systemic upset / feel unwell
hot potato voice
What is treatment for quinsy?
surgical insertion and drainage (of abcess)
antibiotics
What causes acute sinusitis?
Often viral, sometimes bacterial
What are symptoms of acute sinusitis?
facial pain, headache, toothache
fever, malaise, nasal symptoms, post-nasal drip
What is a complication of acute sinusitis?
Brain abcess
therefore ensure acute sinusitis is treated properly
What is treatment for acute sinusitis?
Antibiotics is severe / persistant
What are common upper respiratory tract infections in children?
Acute epiglottitis
Croup
What causes acute epiglottitis?
Haemophilus influenzae B
What is prevention for acute epiglottitis?
vaccination for haemophilus influenzae B
What is croup?
acute obstructive laryngo-tracheo-bronchitis
What causes croup?
virus
Why are children more at risk of fatal respiratory tract infections?
they have narrower airways - easier to block if issue
What is main symptom in children with upper respiratory tract infections?
Stridor - inspiratory sound (because in upper airway, therefore sound made in larynx)
Which disease should you never examine the patient’s throat / mouth?
Children with acute epiglottitis
- risk of actue fatal upper airway abstruction
- ie block airway when airway tipped backwards
What should you do as a dentist if suspected acute epiglottitis?
- admit to hospital
- DO NOT examine throat
What are symptoms of acute epiglottitis?
fever, drooling (hard to swallow), stridor
- in a child
Name the lobes in left / right lung?
Left = upper and lower lobe
Right = upper, middle and lower lobe
What is best treatment for bronchitis?
Rest and fluids
Takes 12-13 days to recover (same if AB taken)
If COPD, asthmatic:
- give AB
Why should pt with COPD be given AB for bronchitis?
They have a lower respiratory reserve.
ie our airways are wider, therefore we have a higher reserve if we become ill and our airways narrow.
What are main causes of bronchitis?
H. influenzae
S. pneumoniae
What are symptoms of bronchitis?
cough and spit
What medication is given for bronchitis?
Amoxycillin or Clarithromycin
If allergy, give Doxycycline
Why aren’t AB given for all respiratory tract infections?
- increase cost / resistance / side effects
What is the main worry about NOT giving AB to treat a respiratory tract infection?
If it’s pneumonia - could be rapidly fatal if not diagnosed / treated
What is pneumonia?
acute respiratory illness
involving alveoli - fill with organisms, exudate = lung consolidation
often bacterial
What are lower respiratory tract infections?
Bronchitis
Pneumonia
Why can pneumonia be rapidly fatal?
Impaired gas exchange
Bacteraemia - sepsis - kidney / lung damage
What does histology look like in pneumonia?
alveoli filled with cells, not air
What does xray look like in pneumonia?
White clouds where alveoli filled
Air filled bronchi still visible
Shadowing
What are symptoms of pneumonia?
Cough, PLUS:
- tachypnoea
- pleuritic pain (esp on inhalation, sharp pain)
- new focal signs in chest (abnormal sounds)
esp if systemically unwell (fever, rigor, tachycardia, sweating)
Why can pleuritic pain be an issue in pneumonia?
Bacteria has travelled from
alveoli - pleura - pleuritic space
When should treatment for respiratory tract infections start?
ASAP (before organism is known - tests may not be conclusive)
How can organisms be identified in respiratory tract infections?
- sputum culture (high sensitivity, low specificity)
- blood culture (high specificity, low sensitivity)
- bronchoalveolar lavage / percutaneous aspirate - rare
- antibody titres (retrospective)
What is bronchoalveolar lavage?
- insert bronchoscopy tube into lungs
- squirt fluid into small part of lung
- collect this fluid for analysis
- rare, but used in lung disease diagnosis
What is percutaneous aspirate?
- needle access via skin into lungs
- aspirate sample of lung using needle
- analysis sample to diagnose lung disease
What is an antibody titre?
- test that measures antibodies in blood
- used in lung disease diagnosis
What specific symptoms relate to different organisms causing pneumonia?
NONE!
There are no symptoms / signs / xray changes associated with different pneumonia-causing organisms.
Organisms present often depends on method of disease contraction
- community acquired
- hospital acquired
- aspiration pneumonia
- immunocompromised
How can pneumonia be acquired?
- community acquired
- hospital acquired
- aspiration pneumonia
- immunocompromised
What is aspiration pneumonia?
If pt is unconscious, they can inhale vomit.
- no cough reflex
- organism often from oral cavity
What % bacteria / viruses cause community acquired pneumonia?
Streptococcus pneumoniae 60-75% Haemophilus influenzae 4-5% Legionella Sp 2-5% Chlamydia Sp 7-16% Mycoplasma pneumoniae 5-18%
Viruses 4-12%
Is streptococcus pneumoniae gram +ve / -ve?
gram +ve
Which community acquired organisms can penicillin combat?
Strep. pneumoniae
Haemophilus influenzae
Which community acquired organisms can clarithromycin combat?
Atypical organisms:
Legionella Sp
Chlamydia Sp
Mycoplasma pneumoniae
Which groups of antibiotics and specific antibiotics are used in treatment of community acquired pneumonia?
Penicillin
- benzylpenicillin
- amoxycillin
Macrolides
- erythromycin
- clarithromycin
Which bacteria are penicillins most effect against?
Streptococcus pneumoniae
Which bacteria are macrolides most effect against?
Atypical organisms:
Legionella Sp
Chlamydia Sp
Mycoplasma pneumoniae
What type of antibiotic would you give a young child with respiratory tract infection?
Macrolides (clarithromycin / erythromycin)
- young ppl usually have atypical organisms.
What is a good combination of antibiotics to give in community acquired pneumonia treatment and why?
amoxycillin and clarithromycin
- covers range of bacteria causing community acquired pneumonia
- amoxycillin is well absorbed and has a broader spectrum
