DON'T SWEAT IT: A CASE OF PID-LUNG DISEASE MISDIAGNOSED AS CYSTIC FIBROSIS

Abstract

<h3>Introduction</h3> Chronic lung disease in primary immunodeficiency is common and contributes to significant morbidity and mortality. Bronchiectasis has a broad differential which includes Cystic Fibrosis and several other disease processes. In patients with primary immunodeficiency, this inflammatory destruction of airway walls is a complication of recurrent pneumonia and immune dysregulation. <h3>Case Description</h3> A 16-year-old boy from Bangladesh with history of Cystic Fibrosis (CF) was referred by pulmonology for management of known hypogammaglobulinemia. Patient came to the United States for treatment of CF-associated severe lung disease. His course in Bangladesh had been complicated by multiple episodes of sinopulmonary infections and failure to thrive secondary to severe diarrhea and pancreatic insufficiency. He had been initially diagnosed with CF in 2019 in Thailand with positive sweat chloride test with additional finding of hypogammaglobulinemia. Chest CT at our institution showed severe bronchiectasis with multifocal consolidations and ground glass opacities consistent with CF. Our immunological evaluation revealed agammaglobulinemia with IgG <109, IgA <2, IgM <5, as well as B-cell and T-cell lymphopenia. Pulmonology then performed repeat sweat chloride testing and genetics which were both negative for CF. GI evaluation revealed evidence of colitis with no pancreatic insufficiency. Patient's history could all be explained by primary immunodeficiency (PID). PID gene panel was unrevealing and whole exome sequencing is pending. Following his diagnosis, patient was managed with IVIG, prophylactic antibiotics, and enteral feeds with great improvement. <h3>Discussion</h3> This case illustrates the importance of early recognition of primary immunodeficiency, especially in resource-poor areas. Hypogammaglobulinemia should be on the differential for childhood-onset bronchiectasis.