TABLE 1

Diagnostic methods and strategy for suspected AW diseases

Least invasive Most invasive
Clinical indicesLung function testsImagingNot or minimally invasive biologic tests/proceduresMore invasive procedures
• Prematurity
• Age at onset of symptoms
• Initial clinical picture
• Patient age
• Acute/chronic
• Time of the year

  • - September (rhinovirus)#

  • - End of year (RSV)#

  • - Start and end of year (influenza)#

• Efficacy of past treatments
• Lung or bone marrow transplant
• Probability scores available

  • - Colom and Teper (obliterative bronchiolitis)

  • - PICADAR score (PCD)

• Algorithm available (PCD)
• Neonatal screening (CF)
• Therapeutic trial

  • - Antibiotics (protracted bacterial bronchitis)

  • - Regular asthma therapy (asthma)

  • - Systemic steroids, long-term or IM (asthma with obstruction not reversible by SABA)

• Spirometry (obstructive or mixed pattern)
• Plethysmography, Raw (suspected distension)
• Rrs, Ros, Rint (↑)
• FeNO

  • - Lower AW ↑ (asthma)

  • - Nasal ↓ (PCD)

• AW BHR
• BD reversibility
• Lung clearance index (CF, PCD)		• Chest X-ray
• Inspiratory and expiratory films (inhaled foreign body)
• Contrast medium; videofluoroscopic swallowing study (tracheo-oesophageal fistula; chronic aspiration)
• CT scan (various, severe disease, CF, non-CF bronchiectasis, TB)

  • - Mosaic pattern (obliterative bronchiolitis)

• CT scan + virtual endoscopy (foreign body, stenosis, obstruction)
• CT scan + contrast

  • - Vascular anomalies

  • - Haemoptysis (embolisation of bronchial or systemic arteries)

• MRI (bronchiectasis, AW malformations, haemangiomas)
• MRI + contrast (vascular abnormalities)
• MRI + ventilation (hyperpolarised gas) and perfusion studies (CF, BPD)
• Octreotide scans, PET scans (tumours; may be negative in carcinoids)		• Blood

  • - RAST tests (allergy)

  • - Immune screen (bronchiectasis)

  • - Genetic tests (CF, PCD)

  • - Serology (infections)

  • - Cotinine

• Sputum

  • - Microbiology (CF, TB)

  • - Inflammatory markers (asthma, CF)

• Naso- and oro-pharyngeal swabs

  • - Virology

  • - Mycoplasma pneumoniae

  • - Chlamydia pneumoniae

• Gastric aspirates
• Nasal brushing (PCD)
• Skin

  • - Skin prick and patch tests (allergy)

  • - Sweat test (CF)

• Urinary cotinine
• Hair cotinine
• Saliva

  • - Cotinine

  • - Genetic tests

• Bronchoscopy

  • - Direct vision (foreign body, AW malformations)

  • - EBUS (older children)

  • - Dynamic (tracheo-bronchomalacia)

  • - Swallow studies (aspiration syndromes)

  • - Bronchoalveolar lavage (asthma, bronchiectasis, CF, protracted bacterial bronchitis, chronic aspiration (lipid-laden macrophages))

  • - Lower AW brushings (PCD)

  • - Biopsy (asthma, TB), tumours (carcinoids: risk of bleeding)

• Surgery (AW malformations, localised bronchiectasis)

  • #: in Europe (Northern Hemisphere). In brackets are indicated the diseases for which the clinical index/test/procedure is frequently concerned. AW: airway; RAST: radioallergosorbent test; EBUS: endobronchial ultrasonography; CF: cystic fibrosis; Raw: airway resistance; Rrs: respiratory resistance; Ros: respiratory resistance measured by oscillometry; Rint: interrupter respiratory resistance; PCD: primary ciliary dyskinesia; FENO: fractional exhaled nitric oxide; CT: computed tomography; RSV: respiratory syncytial virus; TB: tuberculosis; BHR: bronchial hyperreactivity; BD: bronchodilator; MRI: magnetic resonance imaging; BPD: bronchopulmonary dysplasia; PET: positron emission tomography; IM: intramuscular; SABA: short-acting beta-agonist.