[Recurrent atypical mycobacterial infections in the adult: think of autoantibodies against interferon-gamma !]. / Infections récurrentes à mycobactéries atypiques chez l'adulte : attention aux autoanticorps anti-interféron-gamma!

INTRODUCTION: Disseminated non-tuberculosis mycobacterial infections are associated with a defect of the cellular immune response. They have been mainly reported in AIDS patients. Cases related to the presence of anti-interferon-γ autoantibodies are rare. CASE REPORT: We report a non HIV-infected 45-year-old Thai woman, with a past medical history of Graves' disease. She presented with recurrent disseminated and severe non-tuberculous mycobacterial infections that were related to the production of anti-interferon-γ autoantibody. The diagnosis was suspected in the presence of a negative interferon-γ release assay (IGRA) including with the positive control, and evidenced by the identification of specific antibodies. CONCLUSION: Anti-interferon-γ autoantibody production is a rare cause of non tuberculous mycobacterial infection. Such a mechanism should be suspected in non HIV-infected patients and especially in those having an Asiatic ethnicity or an associated immune disorder. A negative IGRA (including with the positive control) is a reliable diagnostic tool and should be completed with the identification of specific autoantibodies.