Which of the following promotes an inflammatory response of chemical pneumonitis?

• A. Meconium aspiration syndrome
• B. Pneumonia
• C. Retained lung fluid
• D. Transient tachypnea of the newborn

Answer: (A)

Meconium aspiration syndrome promotes an inflammatory response of chemical pneumonitis because meconium acts as a chemical irritant when inhaled into the newborn lungs. Its components, including bile salts and pancreatic enzymes, injure the alveolar epithelium and airway mucosa, triggering an inflammatory cascade that increases permeability, causes edema, and impairs surfactant function. This chemical injury leads to alveolar inflammation and patchy atelectasis, hallmarks of chemical pneumonitis.

In contrast, pneumonia is primarily infection-driven inflammation, while transient tachypnea of the newborn and retained lung fluid stem from delayed clearance of fetal lung fluid and edema without the chemical irritant injury that defines chemical pneumonitis.