In 2018, the immunology laboratory at Hospices civils de Lyon developed a measure of the activation of the type 1 interferon pathway and has since been using it routinely. It has been certified as a reference medical biology laboratory for this test: the expression score in blood of six interferon-stimulated genes (ISGs).
- In 2022, the laboratory carried out 2004 ISG expression score measurements at the request of the Reference Centres for Autoimmune and Inflammatory Diseases at the university hospitals of Lyon (n=784), Paris (n=526) and Lille (n=197).
- Most of the patients were women (1.8 per man) and under 20 years of age.
- The reason for ordering the measurement, 46% of which came from paediatric services, was to help with diagnosis or to monitor disease activity.
- The rate of positive results ranged from 86% for monogenic type 1 interferonopathies to 40% for neuroinflammatory syndromes and/or cerebral calcifications.
