T-B+ severe combined immunodeficiency due to CD3delta/CD3epsilon/CD3zeta

A rare T-B+ severe combined immunodeficiency characterized by a T cell-negative, B cell-positive, natural killer (NK) cell-positive immune phenotype. Patients present in infancy or early childhood with recurrent infections. Clinical manifestations may vary in severity depending on the underlying molecular defect, resulting in early death without bone marrow transplantation in some patients.