The most common autoimmune manifestation was cytopenia (17.8%); the most common cytopenia was immune thrombocytopenia, reported in 10 out of 95 patients (10.5%), followed by autoimmune haemolytic anaemia (n=3, 3.1%) and autoimmune neutropenia (n=3, 3.1%); almost all patients with autoimmune cytopenia had splenomegaly (15 out of 17; 88%)There was no statistically siginificant difference in CD3+, CD8+, CD4+CD25highCD127low T reg, CD19, CD19hiCD21loCD38lo, and follicular T helper cells in CVID patients with or without autoimmune manifestations. This evidence concerns the gene CD19 and Splenomegaly.