title: Primary immunodeficiency diseases in Northern Iran.
abstract: BACKGROUND
  Primary immunodeficiency diseases (PID) are a heterogeneous group of inherited disorders, characterised by recurrent severe infections, autoimmunity and lymphoproliferation. Despite impressive progress in identification of novel PID, there is an unfortunate lack of awareness among physicians in identification of patients with PID, especially in non-capital cities of countries worldwide.
  
  
  RESULTS
  This study was performed in a single-centre paediatric hospital in Northern Iran during a 21-year period (1994-2015). Ninety-four patients were included in this study. The majority of cases had antibody deficiencies (37.23%), followed by well-defined syndromes with immunodeficiency in 16 (17.02%), phagocytic disorders in 15 patients (15.95%), complement deficiencies in 15 patients (15.95%), immunodeficiencies affecting cellular and humoral immunity in nine patients (9.57%), disease of immune dysregulation in three (3.19%), and defects in intrinsic and innate immunity in one (1.06%).
  
  
  CONCLUSIONS
  It seems that there are major variations in frequency of different types of PID in different regions of a country. Therefore, reporting local data could provide better ideas to improve the local health care system strategists and quality of care of PID patients.
authors.affiliation: Noncommunicable Pediatric Diseases Research Center, Babol University of Medical Sciences, Babol, Iran; Primary Immunodeficiency Diseases Network (PIDNet), Universal Scientific Education and Research Network (USERN), Babol, Iran.
authors.forename: I
authors.initials: I
authors.lastname: Mohammadzadeh
authors.affiliation: Noncommunicable Pediatric Diseases Research Center, Babol University of Medical Sciences, Babol, Iran; Primary Immunodeficiency Diseases Network (PIDNet), Universal Scientific Education and Research Network (USERN), Babol, Iran.
authors.forename: B
authors.initials: B
authors.lastname: Moazzami
authors.affiliation: Department of Pediatrics, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran.
authors.forename: J
authors.initials: J
authors.lastname: Ghaffari
authors.affiliation: Research Center for Immunodeficiencies, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran; Primary Immunodeficiency Diseases Network (PIDNet), Universal Scientific Education and Research Network (USERN), Tehran, Iran.
authors.forename: A
authors.initials: A
authors.lastname: Aghamohammadi
authors.affiliation: Research Center for Immunodeficiencies, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran; Department of Immunology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran; Network of Immunity in Infection, Malignancy and Autoimmunity (NIIMA), Universal Scientific Education and Research Network (USERN), Boston, MA, USA. Electronic address: rezaei_nima@tums.ac.ir.
authors.forename: N
authors.initials: N
authors.lastname: Rezaei
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007153:Immunologic Deficiency Syndromes / Q000453:epidemiology* / Q000276:immunology; D007223:Infant; D007231:Infant, Newborn; D007492:Iran; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D055815:Young Adult
keywords: Combined immunodeficiencies; Frequency; Hypogammaglobulinaemia; Phagocyte defects; Primary immunodeficiency diseases