CD4 and severe combined immunodeficiency: However, only four patients displayed a severe reduction in CD4+ (<200 cells/mm3) and/or CD4 naive cells (20 cells/mm3), thus fulfilling the criteria for the diagnosis of Late-Onset Combined Immunodeficiency (LOCID) [10]: 3/17 patients in the NR group, 1/18 in the IgG-R and none in IgG/igA-R group.