Successful Stem Cell Transplantation in a Girl with DOCK 2 Deficiency

Introduction The dedicator of cytokinesis 2 (DOCK2) protein deficiency is a very rare, combined immunodeficiency characterized by early-onset lymphopenia, recurrent infections, and lymphocyte dysfunction. The only cure is hematopoietic stem cell transplantation. Result Here, we report a case of an 8-month-old girl who was admitted for severe chronic diarrhea related to chronic inflammatory colitis. The immune assessment showed hypogammaglobulinemia and a decrease in T cells. Genetic study confirmed the diagnosis of DOCK2 deficiency. She underwent haploidentical stem cell transplantation at 10 months. Conditioning regimen was based on Busilvex and fludarabine. Cyclosporine and MMF were used for graft-versus-host prophylaxis. The child is currently asymptomatic after two years of transplantation. Conclusion DOCK2 deficiency is a rare cause of very early-onset inflammatory bowel disease. Early diagnosis and appropriate treatment are fundamental to improve post-HCST prognosis.