Spontaneous occurrence of localized pulmonary interstitial and endolymphatic emphysema in infancy.

Two infants are described with persistent pulmonary interstitial and endolymphatic emphysema of the localized, bullous type, occurring apparently spontaneously. Roentgenographically, the process simulated congenital lobar emphysema in the first patient and bilateral post-infectious pneumatoceles in the second. The histologic features of the lesion were identical to those seen in localized pulmonary interstitial emphysema caused by positive pressure ventilation in newborns with hyaline membrane disease.