Asthma in Children: Diagnosis and Management

Initial Clinical Assessment

• Key Symptoms:

  • Wheezing, cough, breathlessness, chest tightness.
  • Symptoms worsen with triggers (e.g., exercise, cold air, allergens).
  • Personal or family history of asthma or allergic rhinitis.

• Physical Examination:

  • Look for expiratory polyphonic wheeze.
  • A normal examination does not exclude asthma.
  • Immediate treatment for acutely unwell children.

Objective Tests for Diagnosis (Ages 5-16)

• FeNO Test: Diagnose asthma if FeNO ≥ 35 ppb.
• Bronchodilator Reversibility (BDR) with Spirometry: Diagnose if FEV1 increases by ≥12% after bronchodilator use.
• Peak Expiratory Flow (PEF) Variability: ≥20% variation over 2 weeks suggests asthma.
• Additional Tests:
  • Skin prick test for house dust mite or total IgE levels.
  • If blood eosinophils > 0.5 x 10⁹/L, asthma is likely.
  • If unclear, refer to a specialist.

Diagnosis in Children Under 5

• Trial of Treatment Approach:

  • 8-12 week trial of low-dose ICS + SABA (reliever).
  • If symptoms improve, stop treatment and review after 3 months.
  • If symptoms return, restart ICS and reassess in 12 months.
  • Refer to a specialist if asthma is uncontrolled on moderate-dose ICS and LTRA trial fails.

• Refer preschoolers with:

  • 2+ emergency admissions for wheeze in 12 months.
  • Hospitalisation due to asthma symptoms.

Management of Asthma

Pharmacological Treatment (Ages 5-11)

• Step 1: Low-dose ICS (twice daily) + SABA as needed.
• Step 2: If uncontrolled, switch to low-dose MART.
• Step 3: If still uncontrolled, increase to moderate-dose MART.
• Step 4: If still uncontrolled, add LTRA or switch to ICS/LABA combination.

Pharmacological Treatment (Ages 12+)

• Step 1: Start with low-dose ICS/formoterol as needed.
• Step 2: If highly symptomatic, switch to low-dose MART.
• Step 3: If uncontrolled, increase to moderate-dose MART.
• Step 4: If still uncontrolled:
  • Check FeNO and eosinophils.
  • If elevated, refer to a specialist.
  • If normal, add LTRA or LAMA.

Key Points:

• Do not prescribe SABA alone without ICS.
• Ensure correct inhaler technique at every review.
• Consider lowest environmental impact inhaler with correct technique.
• Provide self-management plans and educate families.

Bronchiolitis: Viral Causes, Supportive Care, and Prevention

Overview

• Common viral infection in infants under 2 years old.
• Caused by:
  • Respiratory Syncytial Virus (RSV) (most common).
  • Human rhinovirus, coronavirus, adenovirus, metapneumovirus.
• Highly contagious via coughs, sneezes, and surfaces.

Symptoms and Progression

• Early Symptoms (First 1-3 Days):

  • Runny nose, sneezing, mild cough, mild fever (38°C).

• Severe Symptoms (Days 3-5):

  • Respiratory distress: Tachypnea, retractions, grunting, cyanosis.
  • Auscultation findings: Wheezing, crackles, rhonchi.
  • Severe cases: Hypoxia, apnoea (especially in preterm infants).
  • Course: Symptoms peak at 48-72 hours, improving over 7-14 days.

Management

• Supportive Care (No specific antiviral treatment):

  • Monitor hydration: Offer frequent feeds.
  • Control fever: Paracetamol/Ibuprofen.
  • Use nasal saline to clear secretions.
  • Humidified oxygen for SpO2 < 90%.
  • Nebulised hypertonic saline may reduce symptoms in hospitalised patients.

• Avoid routine use of:

  • Beta-agonists (salbutamol).
  • Corticosteroids.
  • Antibiotics (unless bacterial infection suspected).

Prevention

• Prevent RSV Spread:

  • Frequent handwashing.
  • Avoiding crowded places during RSV season.
  • Keeping sick individuals away from infants.

• High-Risk Infants:

  • Monthly palivizumab injections (RSV prophylaxis) in October-March for:
    • Preterm infants.
    • Infants with chronic lung disease or congenital heart disease.

Cystic Fibrosis (CF): Pathophysiology and Multidisciplinary Management

Pathophysiology

• Autosomal recessive disorder caused by CFTR gene mutations.
• Defective CFTR protein → impaired chloride transport → thick mucus secretions.
• Affects multiple organs:
  • Lungs: Mucus plugging → bronchiectasis, recurrent infections.
  • Pancreas: Blocked ducts → pancreatic insufficiency, malabsorption.
  • Intestines: Meconium ileus, distal intestinal obstruction syndrome (DIOS).
  • Liver: Biliary cirrhosis, cholestasis.

Clinical Features

• Respiratory: Chronic cough, recurrent lung infections, wheezing.
• Gastrointestinal: Fatty stools (steatorrhoea), failure to thrive, meconium ileus.
• Other Signs: Finger clubbing, nasal polyps, infertility.

Diagnosis

• Sweat Chloride Test:
  • ≥ 60 mmol/L = Confirmed CF.
  • 30-59 mmol/L = Indeterminate.
  • < 30 mmol/L = Unlikely CF.
• Genetic Testing: Identifies CFTR gene mutations.

Management (Multidisciplinary Approach)

Airway Clearance

• Chest physiotherapy (twice daily).
• Inhaled dornase alfa (DNase) + hypertonic saline.
• Bronchodilators for wheezing.
• Oxygen therapy if hypoxic.

Infection Control

• Prophylactic antibiotics (flucloxacillin) for infants.
• Inhaled antibiotics (e.g., tobramycin) for chronic Pseudomonas infections.
• Oral azithromycin for exacerbation reduction.
• Avoid cross-infection in CF patients.

Nutritional Support

• High-calorie, high-fat diet.
• Pancreatic enzyme replacement therapy (PERT).
• Vitamin A, D, E, K supplements.

CFTR Modulator Therapy

• Ivacaftor, lumacaftor, elexacaftor-tezacaftor-ivacaftor for specific CFTR mutations.

Monitoring & Prevention

• Annual lung function tests (spirometry).
• Regular chest X-rays & sputum cultures.
• Liver & diabetes screening (CF-related diabetes risk).

Conclusion

Understanding paediatric respiratory disorders is crucial for early diagnosis and effective management. Asthma, bronchiolitis, and cystic fibrosis require specific diagnostic tests, tailored management, and ongoing monitoring to prevent complications and improve quality of life.

References

1. Children’s Health of Orange County (CHOC). (n.d.). 7 Common Respiratory Diseases in Children. Retrieved from https://choc.org/news/7-common-respiratory-diseases/

2. National Institute for Health and Care Excellence (NICE). (2023). Asthma: Diagnosis, Monitoring, and Chronic Asthma Management (NG245) – Recommendations. Retrieved from https://www.nice.org.uk/guidance/ng245/chapter/Recommendations

3. Smith, R. A., & Brown, M. J. (2022). Overview of Respiratory Diseases. In StatPearls. StatPearls Publishing. Retrieved from https://www.ncbi.nlm.nih.gov/books/NBK441959/

4. NHS. (n.d.). Bronchiolitis: Symptoms, Causes, and Treatment. Retrieved from https://www.nhs.uk/conditions/bronchiolitis/

5. TeachMePaediatrics. (n.d.). Cystic Fibrosis: Overview and Management. Retrieved from https://teachmepaediatrics.com/respiratory/lower-respiratory-tract/cystic-fibrosis/

6. Simon, R. H., & Andrews, D. R. (2021). Cystic Fibrosis. In StatPearls. StatPearls Publishing. Retrieved from https://www.ncbi.nlm.nih.gov/books/NBK493206/