🫁 Chapter 2: Cough

Nelson's Pediatric Symptom-Based Diagnosis | Acute · Chronic · Pertussis · Croup · Asthma · Foreign Body · Cystic Fibrosis

🔍 Pediatric Cough: Key Concepts

📊 Acute Cough (<4 weeks)
Viral URI most common. Croup (barking cough, stridor), bronchiolitis (wheezing, RSV), pneumonia (fever, tachypnea), pertussis (paroxysmal + whoop).
🔄 Chronic Cough (>4 weeks)
Consider asthma (nocturnal, exercise-induced), GERD (postprandial, nocturnal), sinusitis, foreign body, cystic fibrosis (digital clubbing, steatorrhea), habit cough (absent during sleep).
⚠️ Pertussis (Whooping Cough)
Paroxysmal cough with inspiratory whoop, post-tussive emesis, lymphocytosis. Diagnosis: PCR or culture. Tx: azithromycin, supportive care. Prevent with Tdap.
💧 Croup (Laryngotracheobronchitis)
Barking seal-like cough, inspiratory stridor, worse at night. Usually viral (parainfluenza). Mild: humidified air. Moderate-severe: dexamethasone + racemic epinephrine.
🧬 Cystic Fibrosis
Chronic productive cough, recurrent pneumonia, P. aeruginosa, bronchiectasis, pancreatic insufficiency, elevated sweat chloride. Newborn screen + CFTR mutation.
🚩 Red Flags
Hemoptysis, stridor, dysphagia, digital clubbing, failure to thrive, cough since birth, persistent focal wheeze (foreign body).

💡 Key Takeaway: Acute cough is usually viral, but chronic cough (>4 weeks) warrants investigation: asthma, GERD, sinusitis, foreign body, or CF. First morning sputum, chest X-ray, spirometry, and sweat test are key diagnostic tools.

🩺 Clinical Approach to Cough: Step-by-Step Algorithm

🔹 Step 1: Differentiate acute (<4 weeks) vs chronic (≥4 weeks)
• Acute: viral URI, croup, bronchiolitis, pneumonia, pertussis.
• Chronic: asthma, GERD, sinusitis, postnasal drip, foreign body, CF, habit cough.
🔹 Step 2: Red flags requiring urgent evaluation
• Stridor, drooling, toxic appearance → epiglottitis/croup.
• Acute onset choking + unilateral wheeze → foreign body aspiration.
• Hemoptysis, cyanosis, respiratory distress.
🔹 Step 3: History & cough characteristics
• Barking cough → croup.
• Paroxysmal + whoop + posttussive emesis → pertussis.
• Nocturnal, exercise-induced → asthma.
• After meals, supine → GERD.
• Productive, chronic purulent sputum → CF, bronchiectasis.
🔹 Step 4: Diagnostic testing
• Chest X-ray (pneumonia, foreign body, hyperinflation).
• Spirometry (asthma, obstruction).
• Sweat chloride test for CF (suspicious: clubbing, steatorrhea, Pseudomonas).
• Barium swallow (aspiration, vascular ring).
• Bronchoscopy (foreign body, airway anomaly).
🔹 Step 5: Management pearls
• Asthma: inhaled corticosteroids + bronchodilators.
• GERD: lifestyle, prokinetics, H2 blockers/PPI.
• CF: airway clearance, pancreatic enzymes, antibiotics for exacerbations.
• Pertussis: azithromycin, isolation.
• Habit cough: suggestion therapy, distraction.