Atypical Phenotype of Predominant Autoimmune Cytopenia and Impaired Perforin Expression in XMEN Syndrome

X-linked immunodeficiency with magnesium defect, Epstein-Barr virus (EBV) infection, and neoplasia (XMEN) is caused by a pathogenic variant in the magnesium transporter 1 (MAGT1) gene. The defect leads to impaired N-glycosylation which affects various immune processes. In this study, we described the disease course, clinical features and laboratory parameters observed in six patients from three families diagnosed with XMEN syndrome.