Is pertussis characterized by a wet cough?

Pertussis Cough Characteristics: Dry, Not Wet

Pertussis is characterized by a dry, paroxysmal cough, not a wet or productive cough. 1

Clinical Presentation and Cough Characteristics

Pertussis (whooping cough) progresses through three distinct phases, each with specific cough characteristics:

1. Catarrhal Phase (1-2 weeks)

   • Initial symptoms resemble a common cold
   • Mild, intermittent cough
   • Rhinorrhea, mild sore throat, minimal or no fever
   • Patients are highly infectious during this phase 1

2. Paroxysmal Phase (4-6 weeks)

   • Distinctive dry, spasmodic cough
   • Series of rapid coughs followed by a characteristic inspiratory "whoop"
   • Posttussive vomiting common
   • No significant sputum production 1

3. Convalescent Phase (2-6 weeks or longer)

   • Gradual resolution of symptoms
   • Decreasing frequency of coughing paroxysms
   • Persistent dry cough that can last for months 1

Key Diagnostic Features

The classic pertussis cough has several distinguishing characteristics:

• Paroxysmal nature: Rapid succession of coughs without intervening inhalation 1
• Inspiratory whoop: High-pitched sound when gasping for breath (more common in children; may be absent in adults) 1
• Posttussive vomiting: Vomiting after coughing episodes 1
• Absence of significant sputum production: Unlike many respiratory infections, pertussis does not typically produce excessive mucus 1

Age-Related Variations

• Infants: May present with apnea and minimal cough; whooping sound less common 1
• Adults and previously vaccinated individuals: May have milder presentation without classic whoop 1, 2
• Elderly: Often present with prolonged cough without other classic symptoms 1

Clinical Implications

Understanding the dry nature of pertussis cough is important for:

1. Differential diagnosis: Distinguishing pertussis from other respiratory infections that typically present with productive coughs
2. Early recognition: Identifying pertussis during the catarrhal phase when antibiotic treatment is most effective 3
3. Infection control: Implementing appropriate isolation measures for patients with suspected pertussis 4

Complications Related to Cough

The forceful, paroxysmal coughing in pertussis can lead to:

• Pneumothorax
• Rib fractures (up to 4% of adults)
• Urinary incontinence (common in women)
• Subconjunctival hemorrhage
• Cough syncope (loss of consciousness in up to 6% of adults)
• Hernias
• Weight loss and sleep disturbance 1

Management Considerations

Recognizing the dry, paroxysmal nature of pertussis cough is crucial for appropriate management:

• Antibiotics (macrolides preferred) are most effective when initiated early but primarily prevent transmission rather than alleviate symptoms once cough is established 3, 2
• Symptomatic treatment of cough is often unsatisfactory
• Vaccination remains the most effective prevention strategy 3

The characteristic dry, paroxysmal cough of pertussis, often accompanied by the inspiratory whoop and posttussive vomiting, is a key diagnostic feature that helps distinguish it from other respiratory infections that typically present with wet, productive coughs.