Model Answer
0 min readIntroduction
Acute respiratory infections (ARIs) are a leading cause of morbidity and mortality in children under five years of age, particularly in developing countries. The clinical presentation of fever, cough, and difficulty breathing, especially in an unimmunized child, necessitates a broad differential diagnosis. A preceding maculopapular rash significantly narrows down the possibilities, pointing towards infections like measles, rubella, or varicella, which can be complicated by secondary bacterial pneumonia. This case presents a 2-year-old with concerning signs of severe respiratory distress, demanding prompt and accurate diagnosis and intervention.
Differential Diagnosis
The clinical picture suggests several possibilities:
- Measles: Highly contagious viral illness, characterized by fever, cough, coryza, conjunctivitis, and a maculopapular rash. Secondary bacterial pneumonia is a common complication.
- Pneumonia (Bacterial/Viral): Inflammation of the lungs, presenting with fever, cough, rapid breathing, and chest indrawing. Can be primary or secondary to a viral infection.
- Bronchiolitis: Common viral infection affecting the small airways, typically seen in infants, causing wheezing and respiratory distress.
- Croup: Viral infection causing inflammation of the upper airway, leading to a characteristic barking cough and stridor.
- Pertussis (Whooping Cough): Highly contagious bacterial infection, characterized by paroxysmal coughing fits.
Most Probable Diagnosis: Measles complicated by Pneumonia
Given the history of a maculopapular rash preceding the respiratory symptoms by approximately 7 days, measles is the most likely diagnosis. The unimmunized status of the child significantly increases the risk of measles infection. The subsequent development of fever, cough, and severe respiratory distress (SpO2 88%, chest indrawing, nasal flaring, bronchial breath sounds, and crepitations) strongly suggests secondary bacterial pneumonia, a frequent and serious complication of measles.
Investigations
- Complete Blood Count (CBC): To assess for leukocytosis (suggestive of bacterial infection) or leukopenia (common in viral infections).
- Chest X-ray: To confirm the presence of pneumonia and assess its extent (lobar, interstitial).
- Measles IgM antibody test: To confirm the diagnosis of acute measles infection.
- Nasopharyngeal swab for Respiratory Viral Panel (RVP): To rule out other viral causes of respiratory illness, such as RSV or influenza.
- Blood Culture: If sepsis is suspected.
- Arterial Blood Gas (ABG): To assess the severity of respiratory compromise and guide oxygen therapy.
Management
Initial Stabilization
- Oxygen Therapy: Maintain SpO2 >90% using supplemental oxygen (nasal cannula, mask).
- Intravenous Fluids: Correct dehydration with appropriate fluid resuscitation.
- Monitoring: Continuous monitoring of vital signs (heart rate, respiratory rate, SpO2, temperature).
Specific Treatment
- Vitamin A: Measles is associated with Vitamin A deficiency. Administer age-appropriate dose of Vitamin A (as per WHO guidelines).
- Antibiotics: Broad-spectrum antibiotics should be initiated empirically to cover common bacterial pathogens causing pneumonia (e.g., ampicillin/sulbactam or ceftriaxone).
- Antipyretics: Paracetamol or ibuprofen to manage fever.
- Nebulization: If wheezing is present, consider nebulized bronchodilators (e.g., salbutamol).
Supportive Care
- Nutritional Support: Ensure adequate caloric intake.
- Isolation: Measles is highly contagious; implement appropriate isolation precautions.
- Monitoring for Complications: Closely monitor for complications such as encephalitis, diarrhea, and secondary bacterial infections.
Conclusion
This case highlights the importance of vaccination in preventing potentially life-threatening infections like measles. The presentation strongly suggests measles complicated by pneumonia in an unimmunized child. Prompt diagnosis, appropriate investigations, and timely initiation of treatment, including vitamin A supplementation and antibiotics, are crucial for improving the child’s prognosis. Public health initiatives focusing on increasing vaccination coverage are essential to reduce the burden of measles and its complications.
Answer Length
This is a comprehensive model answer for learning purposes and may exceed the word limit. In the exam, always adhere to the prescribed word count.