D1.325 - Autoantibodies to interferon-gamma: clinical features, treatment outcomes, and in-vitro monitoring of disease

Autoantibodies against interferon-gamma (IFNg) impair the IFN-g/interleukin-12 (IL-12) pathway. Due to the under-recognition and lack of reliable testing of the disease, patients are met with profound delays in diagnosis and treatment. Using only clinical manifestations as markers of disease status is not ideal as symptoms tend to only present when infections are already severe and disseminated. No treatment guidelines are currently available for this disease. 

Patients with confirmed autoantibodies to IFNg were included in the study. Patient information, including basic demographic data, medical history, laboratory investigations and data, and subsequent progress were collected for analysis. The study explores the effectiveness of using phosphorylation of STAT1 as functional evaluation of the autoantibodies. We also assess the use of rituximab treatment in this disease. 

Patient characteristics between major reported cohorts were compared. We present the longest published follow-up data to date. Serial monitoring of laboratory parameters can predict reinfections and treatment failures. Rituximab treatment significantly reduced hospitalizations. 

We present a comprehensive review of patients with anti-IFNg autoantibodies in Hong Kong.  Continuous in-vitro monitoring allows individualized tailoring of treatment and long-term management.