title: An infant with pulmonary interstitial glycogenosis: clinical improvement is associated with improvement in the pulmonary diffusion capacity.
abstract: Pulmonary interstitial glycogenosis (PIG) is an idiopathic interstitial lung disease of infants. The underlying pulmonary pathophysiology of PIG has not been well characterized. Herein we report a term-gestation infant who presented with persistent tachypnea and hypoxia. A chest CT scan demonstrated a diffuse ground glass appearance and lung biopsy demonstrated increased alveolar septae cellularity with glycogen-containing cells, consistent with a diagnosis of PIG. At 3 months of age, pulmonary function testing included: pre- and post-bronchodilator forced expiratory flows using the raised-volume technique and the ratio of pulmonary diffusing capacity for carbon monoxide to alveolar volume (DLCO /VA ). He was prescribed 5 days of oral prednisolone (2mg/kg/day) and pulmonary function testing (PFT) was repeated at 5, 13, and 20 months of age. Initial PFTs demonstrated reduced forced vital capacity (FVC: Z-score = -2.36) and an increased ratio of forced expiratory volume in 0.5 sec to FVC (FEV0.5/FVC: Z-score = 1.15) with no significant change following an inhaled bronchodilator. There was also a marked reduction in DLCO /VA (Z-score = -4.74) compared to age-matched controls. Follow-up demonstrated progressive clinical improvement as well as an increase in Z-FVC and normalization of DLCO /VA . Our in vivo physiological findings are consistent with previous reports that symptom resolution correlated with histological thinning of the alveolar septae upon repeat lung biopsy. The restrictive lung disease we observed is consistent with expected reduced compliance of an alveolar interstitial lung process like PIG, whereas the absence of a reduction in FEV0.5/FVC confirms the absence of obstructive airway disease.
authors: Department of Pediatrics, Riley Hospital for Children, Indiana University School of Medicine, Indianapolis, Indiana.
authors: Zarmina
authors: Z
authors: Ehsan
authors: Gregory S
authors: GS
authors: Montgomery
authors: Christina
authors: C
authors: Tiller
authors: Jeffrey
authors: J
authors: Kisling
authors: Daniel V
authors: DV
authors: Chang
authors: Robert S
authors: RS
authors: Tepper
mesh_terms: D001944:Breath Tests; D002248:Carbon Monoxide; D018450:Disease Progression; D005541:Forced Expiratory Volume; D005938:Glucocorticoids / Q000627:therapeutic use; D006008:Glycogen Storage Disease / Q000175:diagnosis / Q000188:drug therapy / Q000503:physiopathology*; D006801:Humans; D007223:Infant; D008168:Lung / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology*; D017563:Lung Diseases, Interstitial / Q000175:diagnosis / Q000188:drug therapy / Q000503:physiopathology*; D008297:Male; D011239:Prednisolone / Q000627:therapeutic use; D011653:Pulmonary Diffusing Capacity; D014057:Tomography, X-Ray Computed; D014797:Vital Capacity
chemical_list: D005938:Glucocorticoids; D002248:Carbon Monoxide; D011239:Prednisolone
keywords: pulmonary diffusion capacity; pulmonary interstitial glycogenosis