The following models were proposed: (a) Mannina et al.: hypersplenism, polyarthritis, and FVC less than 80% resulting in an area under the curve (AUC) of 0.9267 [14]; (b) Hartono et al. splenomegaly, autoimmune cytopenia (AITP or AIHA), low serum IgA (<13 mg/dL), and CD21low > 5% [63]; (c) Cinetto et al.: splenomegaly, autoimmune cytopenia (AITP or AIHA), CD21low percentage and DLCO with an AUC of 0.9861 [28]; (d) Cabanero-Navalon et al. proposed splenomegaly, lymphadenopathy, low CD8+ cells in peripheral blood and high Baumann’s CVID-ILD radiologic score with an AUC of 0.969 [64]. Here, CD8A is linked to polyarticular arthritis.