<prompt> Primary cause of hyaline membrane disease isPrematurityOxygen toxicityAlveolar inflammationSurfactant deficiency  <response>: Ans. d Surfactant deficiency. Ref. Nelson, Textbook of Paediatrics, 18th731HYALINE MEMBRANE DISEASE Common in premature, IDM and infants delivered by caesarean section. Clinically manifests shortly after birth dyspnoea and cyanotic attacks. X-ray chest shows ground glass mottling. As HMD progresses, influx of plasma renders the lungs more radio-opaque, reticulogranular shadowing becomes more confluent ground glass haziness is seen with loss of clarity of diaphragm heart. Mortality 33 Hyaline membrane is a homogenous eosinophilic membrane plastering the alveolar ducts and terminal bronchiole in HMD. Rx .-Timely steroids, exogenous surfactant therapy and oxygen not 100 are useful in treatment. 