STAT3 and hyper-IgM syndrome: Among the manifestations of immune dysregulation, inflammatory arthritis has emerged as an important yet underrecognized complication that may occur across multiple IEI categories, including humoral immunodeficiencies (such as X-linked agammaglobulinemia, hyper-IgM syndrome, common variable immunodeficiency, and others), complement deficiencies, disorders of immune dysregulation (STAT3 gain of function mutation, CTLA4 and LRBA haploinsufficiency), and combined immunodeficiencies.