Respiratory

Question 1

5 causes of acute cough

Answer 1

1. Upper respiratory tract infection, tonsillitis, pharyngitis
2. Laryngitis
3. Bronchiolitis, pneumonia
4. Asthma
5. Pertussis, foreign body

Question 2

5 causes of chronic cough

Answer 2

1. Asthma
2. Postnasal drip – repeated coryza, allergic rhinitis, and sinusitis
3. Infection – TB, mycoplasma, psittacosis
4. Uncommon – post pertussis, foreign body, recurrent aspiration
5. Rare – CF, lung collapse, Kartagener syndrome, extrinsic compression of trachea/bronchus by enlarged heart, glands or tumour

Question 3

5 causes of acute stridor

Answer 3

1. Acute laryngotracheobronchitis (croup)
2. Foreign body
3. Acute epiglottitis
4. Uncommon – glandular fever, measles
5. Rare – retropharyngeal abscess, vascular rings

Question 4

Draw a table compairing Epiglottitis, Croup and foreign body clinical features

Answer 4

Question 5

Signs of respiratory distress

Answer 5

• Tracheal tug
• Recession – sternal, subcostal, intercostal
• Nasal flare, head bob
• Count respiratory rate over 30 seconds minimum

Question 6

Croup

Answer 6

• Definition - Inflammation of the upper airway, larynx and trachea (usually triggered by a virus)
• Aetiology - most commonly caused by parainfluenzea,
• peak incidence in winter
• clinical features - (gradual onset, preceded by corzya and fever, barking cough, hoarse voice, stridor, chest recession )
• Risk factors ( pre-existing narrowing of upper airways, previous admissions with severe croup, young age)
• Assesment of severity - See attached
• investigations - minimal
• Treatment - minimal handling, keep with carer, treat mild croup with steroids alone dexamethasone 0.15mg/kg, moderate with steroids alone unless worsens and treat with nebulised adrenaline
• Consider discharge when: Stridor free at rest, AND four hours post adrenaline or 30 minutes post oral steroids
• Parental advice - condition caused by a viral infection, the virus leads to swelling of the voice box (larynx) and windpipe (trachea), General pain relief advice, worsening advice to return if child is struggling to breath, looks very sick, childs lips are blue or child starts to drool. Croup isn’t a virus its a reaction to a virus, so children cannot catch or spread croup,. However, the virus that causes croup can be spread from person to person so while they are unwell they should be kept away from school and childcare. Can last for 3-4 days

Question 7

Epiglottitis

Answer 7

• Definition -
• Aetiology- haemophilus influenza type B prior to vaccination now post vaccination era = streptococcus pyogenes, streptococcus pneumonia, staph aureus
• Clinical features
  
  • Rapid onset over few hours
  • Intensely painful throat – prevents swallowing, speaking, causes drooling & pooling of secretions in the throat
  • Ill toxic febrile child
  • Stridor- later finding in epiglottisi and can seuggest near complete airway obstruction
  • Child sits upright with open mouth to maximise airway/ hyperextension of the neck
  • cough uncommon
• Diagnosis -
  
  • ​clinical diagnosis
  • gold standards is direct visualisation
  • lateral neck xray= enlarged epiglottis protruding from the anterior wall of hypopharynx enlarged epiglottis or “thumb sign”
• Management ​
  
  • Examination under anaesthetic – with anaesthetist, paediatricians, ENT surgeon
  • Intubation – usually no longer than 48 hours
  • Blood cultures then IV antibiotics eg cefuroxime, ceftriaxone

Question 8

Bacterial tracheitis

Answer 8

• Definition - invasive exudative bacterial infection of the soft tissues of the trachea, resulting in a thick, purulent exudate which causes symptoms of upper airway obstruction
• Aetiology - S. aureus - most commonly isolated pathogen, others include - S. pneumonia, s Pyogenes, Moraxella, non- typeable haemophillus
• Epidemiology - more common than epiglottis in vacinnated population mean age 5-7,
• Clinical presentation - Often viral prodrome, brassy cough, high fever and toxicity, respiratory distress, patient can lie flat, does not drool, and does not have dysphagia
• Diagnosis - xrays are not required - lateral neck xray showing steeple sign of the subglottic trachea
• Management - Usual treatment for croup ineffective, IV antibiotics (ceftriaxone), supportive including endotracheal intubation pus seen below the cords during ETT

Question 9

Bacterial causes of respiratory tract infections

Answer 9

Bacteria

Streptococcus pneumonia (+other strep)

Haemophilus influenza

Bordetella pertussis (causes whooping cough)

Mycoplasma pneumonia

Mycobacterium tuberculosis

Question 10

Classifcication of respiratory infections

Answer 10

• According to the level of respiratory tree most involved:
  
  • Upper respiratory tract infection
  • Laryngeal/tracheal infection
  • Bronchitis
  • Bronchiolitis
  • Pneumonia

Question 11

Viral causes of respiratory infections

Answer 11

Viruses (most common)

Respiratory syncytial virus

Rhinovirus

Parainfluenza

Influenza

Adenovirus

Question 12

Types of upper respiratory tract infections

Answer 12

• Common cold (coryza)
• Sore throat (pharyngitis, including tonsillitis)
• Acute otitis media
• Sinusitis

Question 13

The Common Cold

Answer 13

• Aetiology - Viral infection
  
  • >200 Rhinovirus, coronavirus, RSV
  • Spread by direct contact, inhalation of small particles, deposition of large particles
• Epidemiology - common early autum until late spring, young children have 6-8 colds per year
• Clinical features
  
  • Clear/mucopurulent nasal discharge, nasal blocking, fever, cough
  • Usually lasts for 1 week, 10% can last for two weeks
• DDx
  
  • ​
  • Allergic rhinitis = prominent itching and sneezing, nasal eosinophilia
  • Vasomotor rhinitis = may be triggered by irritants, weather changes, spicy food
  • Rhinitis medicamentosa = hx of decongestant use
  • FB = unilateral, foul smelling discharge; bloody secretions
  • Sinusitis = presence of fever, headache or facial pain or periorbital edema, or persistence of rhinorrhoea for more than 14 days
  • Streptococcosis = mucopurulent discharge that excoriates the nares
  • Pertussis = onset of persistent or severe paroxysmal cough
  • Congenital syphilis = persistent rhinorrhoea with onset in the first 3 months of life
• Management
  
  • Symptomatic eg Paracetamol, self-limiting condition

Question 14

Sinusitis

Answer 14

• Key points
  
  1. Common cold results in self-limiting rhinosinusitis
     
     1. 0.5-2% of viral URTI are complicated by acute bacterial sinusitis
  2. Typically ethmoidal and maxillary sinuses are present at birth, but only the ethmoidal sinuses are pneumatized
  3. Maxillary sinuses are not pneumatized until 4 years of age
  4. Sphenoidal sinuses present by age 5, frontal sinuses develop at age 7-8
  5. Ostia draining the sinuses are narrow (1-3mm) and drain into the ostiomeatal complexes in middle meatus
     
     1. Paranasal sinuses normally sterile, maintained by mucociliary clearance system
  6. Classification = acute (<30 days), subacute (1-2 months), chronic (>3 months)
• Etiology (Bacterial)
  
  1. Streptococcus pneumoniae (30%)
  2. Non-typeable Haemophilus influenzae (20%)
  3. Moraxella catarrhalis (20%)
• Risk factors
  
  1. Viral URTI, allergic rhinitis and cigarette smoke exposure
  2. Immune deficiencies – particularly antibody production (IgG, IgG subclasses, IgA), phagocyte dysfunction
  3. Cystic fibrosis, ciliary dysfunction
  4. Other – GERD, anatomic defects (eg. cleft palate), nasal polyps, cocaine abuse, nasal FB
  5. Immunosuppression or BMT predisposes to severe fungal sinusitis (aspergillus, mucor); Cx by intracranial extension
• Clinical manifestations
  
  1. Symptoms
     
     1. Nasal discharge (purulence of little significance)
     2. Nasal obstruction
     3. Maxillary toothache
     4. Unilateral facial pain
     5. Headache; can be worsened leaning forward
     6. Fever
  2. Signs
     
     1. Inflamed nasal mucosa
     2. Pus extending from the middle meatus
     3. Maxillary transillumination (over 9y)
     4. Associated middle ear children
  3. Difficult to diagnose in young children – persistent nasal discharge >10 days is the predominant symptom
• DDX = allergic rhinitis, nasal foreign body, infected adenoids, structural abnormality, pertussis
• Investigations
  
  1. CT = imaging modality of choice
     
     1. Air-fluid levels, opacification and mucosal thickening may be seen however non-specific
     2. NOT used routinely, indicated if
        
        1. Failed medical management
        2. Possible orbital/intracranial complication
        3. Surgery being contemplated
  2. Culturing nasal secretions NOT helpful; sinus puncture for culture is gold standard but rarely done
• Treatment
  
  1. 1^st line = amoxicillin for 10 days
  2. 2^nd line = augmentin
  3. If orbital/intracranial signs = IV antibiotics
  4. Steroid sprays, decongestants and antihistamine treatment have shown NO benefit
  5. Surgery rarely needed
• Complications
  
  1. Orbital cellulitis
  2. Intracranial complications = cerebral abscess, cavernous sinus thrombosis, meningitis, encephalitis, subdural/epidural empyema
  3. Osteomyelitis of the frontal bone = Pott puffy tumour

Question 15

Tonsilitis/ Viral Pharyngitis

Answer 15

• Definition - Pharynitis = inflammation of the pharynx
• Aetiology - Infectious (viral, bacterial), environmental exposures, contact with caustic substances, May be involved in systemic inflammatory conditions (periodic fever, aphthous stomatitis, pharyngitis, adenitis (PFAPA) syndrome, KD IBD, SJS, SLE
• Assessment ​
  
  • Evidence of complications (voice changes, drooling, stridor, trismus torticollis, facial swelling) OR child appears severely unwell à consider potential airway threats [epiglottitis or bacterial tracheitis, retropharyngeal or lateral pharyngeal abscess, peritonsillar abscess, EBV]
  • Risk factors (Indigenous, previous acute rheumatic fever, immunosuppression) à swab + commence antibiotics for GAS
  • Requires hospitalisation (dehydration or severe pain) à swab + commence antibiotics
  • If no conditions met à discharge without antibiotics
• Viral pharyngitis - influenza parainfluenza, adenoviruses, coronviruses, enterovirusus
  
  • Gingiovostomatitis + ulcerating vesicles à HSV; can infection for last 14 days
  • Papuloveiscular lesions or ulcerations in posterior oropharynx à Herpangina caused by enteroviruses
    
    1. HFM disease vesicles or ulcers throughout the oropharynx, vesicles on the palms and soles
    2. Coxsackie A16 + A6, Enterovirus 71 (enterovirus most common in summer)
  • Concomitant conjunctivitis à adenovirus
  • Pharyngeal erythema + Koplik spots à measles
  • Splenomegaly + hepatomegaly à EBV
• Clinical features
  
  • Sore throat, fever, constitutional upset
  • Purulent exudate, fever, tender lymphadenopathy and absence of cough (Centor criteria) suggest bacterial infection
• Treatment
  
  • Supportive management

Question 16

Bacerial pharyngitis - other than GAS

Answer 16

• Rare
• F. necrophorum pharyngitis can rarely cause Lemierre syndrome = internal jugular vein septic thrombophlebitis
  
  1. 80% of Lemierre’s syndrome are called by this bacterium
  2. Patients present with fever, sore throat, exudative pharyngitis, and/or peritonsillar abscess
  3. Symptoms persist and patients develop neck pain and swelling, pt often appears toxic
  4. CXR often shows multiple cavitatory nodules, often bilateral and accompanied by pleural effusion
  5. Fatality of 4-9%

Question 17

GAS pharyngitis/ tonsilitis

Answer 17

• Key points
  
  1. Uncommon before 2- 3 years of age; peak 5-15 years
  2. Most prevalent in winter and spring
  3. Readily spread among siblings
  4. Colonisation can result in asymptomatic carriage OR acute infection
• Pathogenesis
  
  1. M protein important GAS virulence factor that facilitates resistance to phagocytosis
  2. Encoded by the emm gene and determines M type
  3. M protein is immunogenic; an individual can experience multiple types of GAS pharyngitis in a lifetime because natural immunity is M specific
• Clinical manifestations
  
  1. Incubation period of 2-5 days
  2. Rapid onset sore throat and fever
  3. Pharynx red, tonsils enlarged often covered with exudate; may be petechiae on the soft palate and posterior pharynx +/- strawberry tongue
  4. Enlarged and tender anterior cervical LN often present
  5. Associated headache, abdominal pain and vomiting
  6. Rash associated with scarlet fever
     
     1. Patients with GAS that produce streptococcal pyrogenic exotoxin A, B or C
     2. Characteristically fine, red, papular; begins on face then generalised
     3. Circumoral pallor
     4. Blanching, increased in skin creases (Pastia’s lines)
     5. Erythema fades in a few days and then typically peels like sunburn
     6. Sometimes sheet-like desquamation around the free margins of finger nails
  7. Diarrhoea, cough, coryza, ulcerations, croup/laryngitis/hoarseness, conjunctivitis – NOT features of GAS
• Investigations
  
  1. Throat swab + culture
  2. Serology – ASOT + Anti-DNAse B
• Treatment
  
  1. Antibiotics
     
     1. Oral phenoxymethylpenicillin
     2. 2^nd line – cephalexin
     3. Anaphylaxis – roxithromycin
     4. Poor compliance – benzathine pencilin G
     5. NOTE:
        
        1. Antibiotic treatment prevents ARF – highly effective when started within 9 days of illness onset
        2. Does NOT prevent against post-strep GN
  2. Analgesia
     
     1. Corticosteroids – can be very effective
• Post-streptococcal complications
  
  1. Post-streptococcal GN
  2. Post-streptococcal reactive arthritis
  3. PANDAs
• Recurrent pharyngitis
  
  1. Due to = re-infection with same M type if specific Ab has not developed, poor compliance with oral antibiotic therapy, resistance, infection with a new M type

Question 18

Tonsillectomy and Adenoidectomy Indicators

Question 19

Retropharyngeal Abscess and Lateral Pharyngeal Abscess

Answer 19

• Key points
  
  1. Occurs most commonly in children < 3-4 years of age (as retropharyngeal nodes involute after 5 years of age)
  2. Boys > girls; 2/3 of patients have hx of recent ear, nose or throat infection
  3. Usually polymicrobial – GAS, oropharyngeal anaerobic bacteria, Staph aureus
• Pathogenesis
  
  1. Retropharyngeal and lateral pharyngeal LN drain the mucosal surfaces of the upper airway and digestive tracts are located in the retropharyngeal space.
  2. Localized infection of oropharynx –> Nodes infected, which then can progress through 3 stages: cellulitis, phlegmon, abscess –>LN in the deep neck spaces communicate – allowing bacteria from cellulitis or node abscess to spread to other nodes
• Microbiology
  
  1. Usually polymicrobial
  2. The predominant bacterial species are Streptococcus pyogenes (GAS), Staphylococcus aureus (including MRSA), and respiratory anaerobes
• Clinical manifestations
  
  1. Symptoms
     
     1. Sore throat, neck pain
     2. Fever, irritability and reduced oral intake
     3. Drooling
     4. Neck stiffness, torticollis and refusal to move neck
     5. Muffled voice, stridor, respiratory distress, OSA
  2. Signs
     
     1. Bulging posterior pharyngeal wall <50% of infants
     2. Cervical lymphadenopathy
     3. Bulge of lateral pharyngeal wall with medial displacement of tonsil – for lateral pharyngeal abscess
• DDx = epiglottitis, FB, meningitis, lymphoma, haematoma, vertebral osteomyelitis
• Investigations
  
  1. Lateral neck X-ray
     
     1. Prevertebral space is increased in depth compared with the anteroposterior measurement of the adjacent vertebral body
     2. Children <5 years
        
        1. Retropharyngeal space usually HALF the width of the adjacent vertebral body
        2. Considered widened if it is greater than a full vertebral body at C2 or 3 when the spine is properly extended
  2. CT with contrast – imaging modality of choice
• Management
  
  1. Incision and drainage – usually required
  2. IV antibiotics
• Complications
  
  1. Airway obstruction
  2. Aspiration pneumonia
  3. Mediastinitis
  4. Thrombophlebitis of the internal jugular vein and erosion of the carotid artery sheath

Question 20

Peritonsillar Cellulitis/ And or Abscess = Quinsy

Answer 20

• Key points
  
  1. Relatively common compared to deep neck infections
  2. Caused by bacterial invasion through the capsule of the tonsil à cellulitis and/or abscess formation
  3. Typically adolescent with recent history of pharyngitis
• Clinical manifestations
  
  1. Symptoms
     
     1. Sore throat, fever
     2. Trismus and dysphagia
  2. Signs
     
     1. Asymmetric tonsillar bulge with displacement of the uvula; diagnostic but may be difficult to identify
• Investigations
  
  1. CT if unclear clinical diagnosis
• Treatment
  
  1. Incision + drainage
  2. Antibiotic therapy

Question 21

Acute Otitis media

• Clinical features
• pathogens
• treatment
• complications

Answer 21

• Clinical features
  
  • Pain in ear, fever, irritability, pulling at affected ear
  • Tympanic membrane: red, bulging, loss of normal light reflection +/- perforation of eardrum with visible pus
• Pathogens
  
  • Viral – RSV
  • Bacterial – pneumococcus , haemophilus influenza, group B strep, Moraxella catarrhalis
• Treatment
  
  • Paracetamol for pain
  • Amoxicillin – shortens duration
• Complications
  
  • Otitis media with effusion (glue ear) conductive hearing loss and ear ache, interference with speech development
  • Mastoiditis
  • Meningitis

Question 22

Otitis Media with effusion

• Causes
• Clinical features inside th ear
• complications
• Treatment

Answer 22

• Caused by mucus in the middle ear
• Effusion of fluid in middle ear is very common after URTI
• Usually short lived and not considered pathological unless fluid has been there for at least 3 months
• Causes conductive hearing loss; signs of infection are absent
• Tympanic membrane – dull and retracted, yellow or grey in colour
• If persistent grommet insertion