Pulmonary interstitial Glycogenosis – a systematic analysis of new cases

Background: Pulmonary interstitial glycogenosis (PIG) is a rare interstitial lung disease in children. The clinical hallmark is a rapid onset with respiratory distress and hypoxemia shortly after birth in the absence of an infectious cause or a surfactant dysfunction syndrome. The diagnosis can only be made by lung biopsy. The histopathological pattern defining PIG can exist in diffuse or patchy distribution. Only few cases have been reported. Not much is known on clinical features, outcomes, CT imaging and histopathology. Methods: The clinical course, CT-scans and tissue samples of children diagnosed with PIG were collected and systematically re-analysed by clinicians, radiologists and pathologists all specialized in interstitial lung diseases in children. All data were uploaded into the Kidslungregister for follow up. Results: 11 children diagnosed with PIG were included in this study. All presented with respiratory distress shortly after birth. More than half of the children were diagnosed with additional abnormalities, especially congenital heart defects. The CT-scan of the lungs showed mainly groundglass opacities, consolidations and septal thickening. Of interest each tissue sample had signs of reduced alveolarization. The prognosis was favourable in almost all cases. When systemic glucocorticosteroids were given a fast improvement was noticed. Conclusion: PIG is a interstitial lung disease in infants with mostly favourable outcome. As alveolar growth retardation was present in all subjects this can support a theory of an underlying maturation delay. In all infants with congenital heart defects and unexplained respiratory distress an interstitial lung disease due to PIG should be considered.