INFECTIONS OF THE RESPIRATORY SYSTEM Flashcards
What factors make children more susceptible to the effects of respiratory tract infection than adults?
More compliant chest wall
Fatiguability of respiratory muscles
Increased mucous gland concentration
Poor collateral ventilation
Low chest wall elastic recoil
What is the medical name for the common cold?
Acute nasopharyngitis
What is the main virus to cause acute nasopharyngitis in children?
Rhinovirus
In a child with pharyngitis or tonsillitis, what signs might point to the infective organisms being bacterial rather than viral?
Purulent exudate
Lymphadenopathy
Severe pain
What are the complications of pharyngitis and tonsillitis?
Retropharyngeal abscess
Peritonsillar abscess (quinsy)
Poststreptococcal glomerulonephritis
Rheumatic fever
What are the indications for tonsillectomy?
The indications for tonsillectomy are controversial. NICE recommend that surgery should be considered only if the person meets all of the following criteria:
- Sore throats are due to tonsillitis (i.e. not recurrent upper respiratory tract infections)
- The person has five or more episodes of sore throat per year
- Symptoms have been occurring for at least a year
- The episodes of sore throat are disabling and prevent normal functioning
Other established indications for a tonsillectomy include:
- Recurrent febrile convulsions secondary to episodes of tonsillitis
- Obstructive sleep apnoea, stridor or dysphagia secondary to enlarged tonsils
- Peritonsillar abscess (quinsy) if unresponsive to standard treatment
What are the organisms responsible for acute otitis media?
Viral:
- RSV
- Influenza
Bacteria:
- Pneumococcus
- H. influenzae
- group B streptococci
- Moraxella catarrhalis
What are the clinical features of otitis media?
Sore ear
Fever
Vomiting
Distress
Remember that only older toddlers will localize pain to their ear. Therefore ear drums should be checked in all febrile children.
Hearing loss is only really associated with otitis media with effusion
What will examination of the ear reveal in someone with acute otitis media?
Red eardrum Loss of light reflex Bulging eardrum Perforation might have occurred Purulent discharge
Why might someone have hearing loss as a result of otitis media?
In those prone to URTIs, it is common for middle ear fluid to persist (effusion), causing a conductive hearing loss and an increased susceptibility to re-infection.
Why might an effusion of the middle ear occur without otitis media?
Poor eustachian tube ventilation due to enlarged adenoids or allergy.
How do you treat middle ear effusions?
Normally it will clear by itself.
If it is persistent it can be surgically drained through grommet insertion.
What is the medical name for croup?
Acute laryngotracheobronchitis
What is the organism that most commonly causes croup?
Parainfluenza virus
What is the peak age of incidence for croup?
Second year of life
What are the clinical features of croup?
Coryza Fever Barking cough Stridor Typically worse at night
What is the important differential to think about when a child presents with features of croup?
Acute epiglottitis
How do we treat croup?
CKS recommend giving a single dose of oral dexamethasone 0.15mg/kg to all children regardless of severity. Otherwise management is usually supportive and most children will improve within 24 hours.
A child will need hospitalisation if:
- Under 12 months old
- Severe systemic illness (however, must consider acute epiglottitis)
- Signs of fatigue or respiratory failure
In these cases dexamethasone 0.15mg/kg or nebulised budenoside 2mg has been shown to have benefits.
What is the scoring system that separates the severity of croup into mild, moderate and severe?
Westley scoring system
What are the clinical features of diphtheria infection?
Sore throat Fever Lymphadenopathy Respiratory distress (stridor) Thick, grey material covering back of throat
How common is diphtheria infection?
The vaccination programme has made it very rare for children born and raised in the UK to become infected, however, it is still endemic in some countries and imported cases do occur.
What is the organism responsible for acute epiglottitis?
Haemophilus influenzae type B
What is the peak age group for developing acute epiglottitis?
1-6 years old
What are the clinical features of acute epiglottitis?
Rapid onset Intensely painful throat Fever Unable to speak or swallow Muffled voice Soft inspiratory stridor
Child is normally sat up with an open mouth to maximise airway. This may cause drooling.
How do you manage a child with acute epiglottitis?
This child is severely unwell and their airway may close at any point. In light of this, they should not be examined and blood should not be taken as any distress can precipitate the closing of the airway.
The child needs to be managed in the resuscitation room. A senior ENT paediatrician and an anaesthetist should be present for examination and intubation under general anaesthetic.
Once the airway is secured, bloods should be taken for culture and IV cefuroxime (3rd generation) should be started.
Intubation is not usually required for longer than 48 hours.
How common is acute epiglottitis?
Vaccination against H. influenzae type B has meant that it is very rare.
What are the organisms that cause bacterial tracheitis?
S. aureus
H. influenzae
Streptococci
Neisseria
What are the clinical features of bacterial tracheitis?
Systemically unwell Fever Respiratory distress Stridor Hoarse voice No drooling (in contrast to acute epiglottitis)
How do you manage a child with bacterial tracheitis?
As with acute epiglottitis, you need to secure the airway and any add stress to the child may lead to the airway completely closing, therefore you should not examine the throat or take blood. The airway should be secured by an anaesthetist and paediatric ENT consultant.
What pathogens are most likely to cause a pneumonia in a neonate?
Most likely - Group B streptococci
Less likely:
- E. coli
- Chlamydia trachomatis
- Listeria monocytogenes
What pathogens are most likely to cause a pneumonia in an infant?
Most likely - Viruses - RSV, adenovirus
Less likely:
- S. pneumoniae
- H. influenzae
- Bordetella pertussis
What pathogens are most likely to cause a pneumonia in a child?
Most likely:
- S. pneumoniae
- H. influenzae
- Group A strep
Less likely:
- Mycoplasma pneumoniae (over 5 years of age)
What are the clinical features of pneumonia in children or infants?
Fever
Breathlessness
Cough (may not appear productive but will be wet)
Pain coughing
Decreased breath sound (less clear in infants)
Dullness to percussion (less clear in infants)
Bronchial breathing (less clear in infants)
Crackles
Effusion
What investigations would you do in a child who presents with signs and symptoms consistent with pneumonia?
Blood cultures
FBC
CRP
Nasopharyngeal aspirate
X-ray should only be done in children if there is a failure to respond to treatment or if complications such as effusion are suspected.
What would suggest a bacterial pneumonia rather than a viral one?
Polymorphonuclear leucocytosis
Lobar consolidation
Pleural effusion
What are the first line antibiotics for a child with a mild - moderate pneumonia?
Penicillin
What are the antibiotics used for a child with a severe pneumonia?
Cefuroxime and flucloxacillin
What antibiotics are indicated for a child with pneumonia caused by mycoplasma?
Clarithromycin
What are the complications of pneumonia in children?
Pleural effusion
Empyema
If a child has recurrent or persistent pneumonia, what underlying causes might you suspect?
Inhaled foreign object
Congenital abnormality of the lungs
Cystic fibrosis
Tuberculosis
What is the pathogen most commonly associated with bronchiolitis?
RSV (respiratory syncytial virus)
What is the peak incidence age for bronchiolitis?
3-6 months
Why do babies tend not to get bronchiolitis before 3 months of age?
Maternal IgG provides protection to newborns
What are the less common causes of bronchiolitis?
Mycoplasma
Adenoviruses
What are the risk factors that make bronchiolitis a more serious problem?
Bronchopulmonary dysplasia - prematurity
Congenital heart disease
Cystic fibrosis
Down syndrome
What are the clinical features of bronchiolitis?
Coryzal symptoms Fever Dry cough Respiratory distress Wheezing Chest hyperinflation Bilateral fine inspiratory crackles Feeding difficulties due to dyspnoea
What investigations might be done in a baby with signs consistent with bronchiolitis to confirm the diagnosis?
Immunofluorescence of nasopharyngeal secretions may show RSV
What signs would make you think that a baby was suffering only a mild case of bronchiolitis and how would they be managed in this case?
Continuing to feed well
Resp rate of less than 40
Minimal intercostal recession
SpO2 of more than 92%
Managed at home - regular review
What signs would make you think that a baby was suffering a moderate case of bronchiolitis and how would they be managed in this case?
Difficulty feeding
Moderate tachypnoea (more than 40 but less than 60)
Marked intercostal recession
SpO2 of 92% or less
Admit to hospital
Nasopharyngeal aspirate to confirm RSV and hence place in side room
O2 via nasal cannulae or head box
Fluids IV or nasogastrically
What signs would make you think that a baby was suffering a severe case of bronchiolitis and how would they be managed in this case?
Resp rate >70
Recurrent episodes of apnoea
Severe recession
Hypoxia in air
Admit to ICU or HDU
High concentration inspired O2
Intubation and assistive ventilation for respiratory failure or recurrent severe apnoea
IV fluids
What are the complications of bronchiolitis?
A subset are more likely to develop asthma
What is the medical name for whooping cough?
Pertussis
What is the organism responsible for whooping cough?
Bordetella pertussis
How is whooping cough spread and what is the incubation period?
7-10 days
Over what period is a child suffering from whooping cough infectious?
7 days after exposure to 3 weeks after onset of paroxysmal cough
What is the whooping aspect of whooping cough?
The whoop is the inspiratory phase where the child suddenly gasps for air as they cannot control the cough.
What are the clinical features of whooping cough?
Paroxysmal cough with an inspiratory ‘whoop’ which is worse at night
Child may go blue and vomit due to intensity of cough
Nosebleeds and subconjunctival haemorrhage may occur after vigorous coughing.
How do you diagnose whooping cough?
A marked lymphocytosis (over 15.0 x 10^9/L) is characteristic
Pernasal swab - Organism can be cultured
How do you treat whooping cough?
Erythromycin given early in disease eradicates the organism and reduces infectivity but does not shorten duration of disease.
What are the complications of whooping cough?
Pneumonia
Convulsions
Apnoea and death
Bronchiectasis
