Reticular dysgenesia is a very rare, autosomal recessive immunodeficiency classified within the severe combined immunodeficiencies (SCID). This disorder is caused by a hematopoietic stem cell defect that results in absence of granulocytes, macrophages, and lymphocytes. It is characterized by lymphoid and thymic hypoplasia with absent cellular, lymphopenia, congenital agranulocytosis, and humoral immunity functions. Affected individuals die by overwhelming infections within a few days or weeks after birth. To date, only few dozens of cases have been described worldwide.