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Published on: October 19, 2013
Pulmonary alveolar proteinosis in infants
1Department of Paediatrics, Aomori Central Hospital, Higashi-Tsukurimichi, Japan.
Insights
Elevated surfactant protein A in bronchial alveolar lavage fluid may aid in diagnosing infantile pulmonary alveolar proteinosis (PAP) in siblings. This finding suggests a potential diagnostic marker for this rare lung condition.
Area of Science:
- Pulmonology
- Genetics
- Biochemistry
Background:
- Pulmonary alveolar proteinosis (PAP) is a rare lung disease characterized by surfactant accumulation.
- Investigating infantile forms of PAP is crucial for understanding disease mechanisms and diagnosis.
Observation:
- Two siblings presented with infantile pulmonary alveolar proteinosis (PAP) without congenital respiratory distress.
- Histological analysis revealed surfactant protein staining in lung tissue.
- Molecular analysis confirmed messenger RNA expression for surfactant protein B (SP-B), ruling out SP-B defects typical of congenital PAP.
Findings:
- Elevated concentrations of surfactant protein A (SP-A) were observed in the bronchial alveolar lavage (BAL) fluid of one patient.
- The absence of SP-B defects suggests a non-congenital form of PAP.
Implications:
- Elevated SP-A in BAL fluid may serve as a diagnostic clue for infantile PAP.
- Further research into SP-A's role could refine diagnostic strategies for PAP.
- Understanding familial PAP cases can illuminate genetic and molecular underpinnings.
Unlabelled:
We investigated the histological and molecular characteristics of pulmonary alveolar proteinosis (PAP) in two siblings (a brother and sister) who did not exhibit respiratory distress at birth but who each developed symptoms during infancy. Histological analysis of lung specimens showed positive staining for surfactant proteins in both patients. The polymerase chain reaction revealed expression of messenger RNA for surfactant protein B (SP-B) in the lung specimens. No defect in SP-B which is characteristic of the congenital form of PAP was observed. The concentration of surfactant protein A (SP-A) in bronchial alveolar lavage (BAL) fluid was elevated in patient 1 suggesting the BAL concentration of SP-A may be a clue to the diagnosis of this form of PAP.
Conclusion:
The accumulation of surfactant protein A in two siblings with an infantile form of pulmonary alveolar proteinosis could be a clue to the diagnosis.
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