Enaud, Laurent; Hadchouel, Alice; Coulomb, Aurore; Berteloot, Laureline; Lacaille, Florence; Boccon-Gibod, Liliane; Boulay, Vincent; Darcel, Francoise; Griese, Matthias; Linard, Mélinée; Louha, Malek; Renouil, Michel; Riviere, Jean-Pierre; Toupance, Bruno; Verkarre, Virginie; Delacourt, Christophe; de Blic, Jacques:
Pulmonary alveolar proteinosis in children on La Reunion Island: a new inherited disorder?
In: Orphanet Journal of Rare Diseases
Background: Pulmonary alveolar proteinosis (PAP) is very rare in children. Only a few small series have been published, with little information about long-term progression. The objective of our study was to describe the clinical, radiological and pathological features, and the long-term course of PAP in a cohort of 34 children from La Reunion Island. Methods: Data were retrospectively collected from medical files. Radiological and pathological elements were reviewed by two pediatric radiologists and three pathologists, respectively. Results: Thirteen cases were familial and 32/34 (94%) cases were family connected. Disease onset occurred in the first six months of life in 82% of the patients. Thoracic computed tomography scans showed the typical "crazy-paving" pattern in 94% of cases. Respiratory disease was associated with a liver disorder, with the detection of liver enlargement at diagnosis in 56% of cases. The course of the disease was characterized by frequent progression to chronic respiratory insufficiency, accompanied by the appearance of cholesterol granulomas and pulmonary fibrosis. Overall prognosis was poor, with a mortality of 59% and an overall five-year survival rate from birth of 64%. Whole-lung lavages were performed in 21 patients, with no significant effect on survival. Liver disease progressed to cirrhosis in 18% of children, with no severe complication. Conclusions: PAP in children from la Reunion Island is characterized by an early onset, associated liver involvement, poor prognosis and frequent progression to lung fibrosis, despite whole-lung lavages treatment. The geographic clustering of patients and the detection of many familial links between most of the cases strongly suggest a genetic etiology, with an autosomal recessive mode of inheritance.