Hyaline Membrane Disease of Newborn Infants Its etiology and significance. Pulmonary hyaline membrane and congenital alveolar dysplasia*

Abstract

Summary 1) Hyaline membrane disease, as a pathological entity was studied histologically and biochemically. Histochemical tests routinely available, failed to reveal specific identifiable characteristics between hyaline membrane and other interalveolar foreign amorphous matter. 2) Observation from our experimental results on rabbits and from autopsied materials of newborns and others, disclosed that hyaline membrane is a pattern of membranous alveolar lining and is derived from any source of inflammatory exudate, edema fluid and probably from aspirated amniotic sac content. 3) Hyaline membrane and congenital alveolar dysplasia (Mac Mahon) are of distinctly different entities. Hyaline membrane is a foreign matter precipitated over the basement membranes of terminal air spaces, while the latter is a developmental defect of distal respiratory structures.