Benralizumab for Prednisone-Dependent Eosinophilic Asthma Associated With Novel STAT3 Loss of Function Mutation

Some severe asthmatic patients experience frequent bacterial respiratory tract infections, which contribute significantly to their disease burden, and often are attributed to their use of systemic corticosteroids and comorbid bronchiectasis. We report a case of a 58-year-old woman who had prednisone-dependent asthma and exacerbations with intense mixed eosinophilic and neutrophilic bronchitis. Autosomal dominant hyper-IgE syndrome, which is a primary immunodeficiency characterized by elevated IgE, eosinophilia, and recurrent infections, caused by a novel pathogenic mutation in STAT3 was identified as the cause of her airway disease. We believe that this is the first report of the demonstration of an IL-5 driven eosinophilia that is associated with a STAT3 mutation that was treated successfully with an anti-IL5 biological.