Autoimmune pulmonary alveolar proteinosis in an adolescent girl with rapidly progressive dyspnea

Autoimmune pulmonary alveolar proteinosis (PAP) is a rare disease, especially in pediatrics, but important to consider, as it may avoid unnecessary and/or invasive investigations and delayed diagnosis. This case report highlights an adolescent girl with rapid onset dyspnea but an unremarkable physical exam and initial testing. However, due to a high index of suspicion, a chest computed tomography (CT) scan was done, revealing a "crazy paving" pattern, which then prompted expedited assessment. This finding, however, is not as specific as often discussed and has a broad differential diagnosis, which will be reviewed in detail as part of this case. Furthermore, this report demonstrates a diagnostic approach for PAP that avoids lung biopsy, previously considered to be required for diagnosis of PAP, but is increasingly becoming unnecessary with more advanced blood tests and understanding of their sensitivity and specificity. Additionally, management strategies for PAP will be briefly discussed.