distribution of primary immunodeficiency disorders diagnosed in a tertiary referral center, tehran, iran (2006-2013)

background: primary immunodeficiency disorders (pid) are a group of hereditary disorders characterized by an increased susceptibility to severe and recurrent infections, autoimmunity, lymphoproliferative disorders, and malignancy. objective: to evaluate the demographic and clinical data of pid patients diagnosed in a referral pediatric hospital. method: all pid cases with a confirmed diagnosis, according to the criteria of international :union: of immunological societies, who were referred to the children’s medical center in tehran, iran, between march 2006 and march 2013 were enrolled in this retrospective cohort study. results: three-hundred and seven pid patients were investigated. predominantly antibody deficiencies were the most common group of pid observed in 118 cases (38.4%), followed by the well-defined syndromes with immunodeficiency in 52 (16.9%), congenital defects of phagocyte in 45 (14.7%), combined immunodeficiencies in 36 (11.7%), autoinflammatory disorders in 34 (11.4%), immune dysregulation in 11 (3.6%), complement deficiencies in 7 (2.3%), and defects in innate immunity in 3 (1%). selective iga deficiency was the most prevalent disorder which affected 46 individuals (14.9%). the median diagnostic delay was 15 months. conclusion: increased awareness and availability of diagnostic tests could result in the better recognition of more undiagnosed pid cases and a decrease in diagnostic delay.