We present a 21-year-old man with common variable immunodeficiency (CVID) and a phenotype of immune dysregulation similar to CTLA-4 haploinsufficiency characterized by autoimmune cytopenia, inflammatory bowel disease (IBD), lymphoproliferation (GLILD), autoimmune encephalitis, and humoral deficiency requiring multiple immunosuppressants (Figure 1). Here, CTLA4 is linked to common variable immunodeficiency.