A 3-month-old female infant from rural Maharashtra presents with a 2-week history of paroxysmal cough that has progressively worsened. The mother reports that the cough is non-productive, occurs in clusters, and is followed by a high-pitched inspiratory sound. The infant has had no fever. On examination, she appears well between coughing episodes but becomes cyanotic during paroxysms. She has not received any vaccinations. Nasopharyngeal aspirate PCR is positive for Bordetella pertussis. What is the most appropriate immediate management?

Explanation

## Pertussis Management in Infants **Key Point:** Pertussis in infants <6 months requires hospitalization, close monitoring, and antibiotic therapy. Supportive care is as critical as antimicrobial therapy. ### Clinical Context This 3-month-old presents with classic pertussis: paroxysmal cough with post-tussive whoop, cyanosis, and confirmed B. pertussis on PCR. At this age, pertussis carries high morbidity and mortality risk due to: - Immature airway reflexes - Risk of apnea and respiratory failure - Potential for secondary bacterial pneumonia - Nutritional compromise from feeding difficulty ### Management Strategy | Component | Rationale | |-----------|----------| | **Hospitalization** | Infants <6 months require close observation for apnea, hypoxia, feeding intolerance | | **Oxygen/Monitoring** | Continuous pulse oximetry, supplemental O₂ if SpO₂ <92%, apnea monitoring | | **Azithromycin** | First-line antibiotic; 10 mg/kg/day × 5 days eliminates nasopharyngeal carriage and reduces transmission | | **Supportive nutrition** | NG feeding if coughing interferes with oral intake | | **Avoid cough suppressants** | Codeine/dextromethorphan contraindicated; they worsen mucus retention | **High-Yield:** Antibiotics in pertussis do NOT shorten the paroxysmal phase (which lasts 2–8 weeks) but DO reduce infectivity and prevent complications. Erythromycin is an alternative if azithromycin unavailable, but azithromycin is preferred due to better tolerability. **Clinical Pearl:** The "whooping" sound may be absent in infants <6 months; instead, they present with apnea, gasping, or cyanotic episodes. Do not be misled by absence of whoop. ### Why Supportive Care Is Essential Infants with pertussis are at high risk for: - Apneic episodes (can be life-threatening) - Hypoxia and secondary pulmonary hypertension - Failure to thrive - Seizures from hypoxia or metabolic derangement Hospitalization with continuous monitoring is standard of care for all infants <6 months with pertussis, regardless of severity at presentation. [cite:Park 26e Ch 8]