A preterm neonate at 28 weeks gestation develops progressive respiratory distress from birth with grunting, subcostal retractions and central cyanosis. CXR shows bilateral diffuse ground-glass opacity with air bronchograms. The deficit responsible is:
- A Meconium aspiration
- B Surfactant deficiency (dipalmitoylphosphatidylcholine) ✓
- C Group B Streptococcal pneumonia
- D Pulmonary hypoplasia
Explanation
Respiratory distress syndrome (RDS/HMD) in preterm neonates results from deficiency of surfactant, primarily dipalmitoylphosphatidylcholine (DPPC). Surfactant reduces alveolar surface tension, preventing atelectasis. Its absence leads to progressive atelectasis, reduced compliance and the classic CXR pattern of bilateral reticulogranular (ground-glass) opacification with air bronchograms. Meconium aspiration occurs in term/post-term births with thick meconium. GBS pneumonia can mimic RDS but has an infectious context. Pulmonary hypoplasia is associated with oligohydramnios (Potter sequence).
Reference: Ghai Essential Pediatrics, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.