Infections due to various atypical mycobacteria in a Norwegian multiplex family with dominant interferon-γ receptor deficiency

Background. Atypical mycobacteria can cause systemic infections in patients with certain types of immunodeficiency. Methods. Clinical samples were decontaminated and cultured to assess the presence of mycobacterial species. Gene sequencing was performed to reveal interferon-gamma receptor 1 ( IFN- gamma R1) deficiency. Results. The index patient received a diagnosis of dominant IFN- gamma R1 deficiency during treatment for a serious infection due to atypical mycobacteria. She belongs to a Norwegian multiplex family comprising 3 generations and 5 patients with dominant IFN- gamma R1 deficiency. Four of these patients have been treated with tuberculostatics because of extensive infection due to atypical mycobacteria, such as Mycobacterium avium-intracellulare, Mycobacterium scrofulaceum, Mycobacterium bovis (bacille Calmette-Guerin), Mycobacterium bohemicum, and Mycobacterium gordonae. Two of the patients have also received subcutaneous injections of IFN-gamma. One family member with the deficiency has not received treatment and is still healthy at 13 years of age. Conclusions. Serious infection due to atypical mycobacteria should initiate a search for primary immunodeficiencies, particularly IFN- gR1 deficiency. Treatment with IFN-gamma should be started when serious infection due to atypical mycobacteria is verified and dominant partial IFN-gamma R1 deficiency is suspected.