title: Recurrent macrophage activation syndrome associated with heterozygous perforin W374X gene mutation in a child with systemic juvenile idiopathic arthritis.
abstract: BACKGROUND
  Recurrent macrophage activation syndrome (MAS) is rarely reported.
  
  
  OBJECTIVE
  To describe recurrent MAS in a 2.5-year-old girl with systemic juvenile idiopathic arthritis and heterozygous perforin mutation, which may have a role in the patient's first recurrence despite use of the HLH-2004 treatment protocol.
  
  
  METHODS
  In the presented case, MAS was initially controlled after the addition of etoposide to the treatment regimen. However, recurrence occurred 6.5 months after cessation of the HLH-2004 protocol. Subsequent recurrences may have occurred because of the family's noncompliance with treatment.
  
  
  CONCLUSIONS
  The patient's extremely high serum ferritin level (267,054 ng/mL) and the recurrent course of MAS may have been because of the coexistence of juvenile idiopathic arthritis and heterozygous perforin W374X mutation. We suggest to search for mutations in HLH genes in recurrent MAS cases.
authors.affiliation: Division of Pediatric Hematology, School of Medicine, Hacettepe University, Ankara, Turkey. suleunal2003@hotmail.com
authors.forename: Sule
authors.initials: S
authors.lastname: Unal
authors.forename: Gunay
authors.initials: G
authors.lastname: Balta
authors.forename: Hamza
authors.initials: H
authors.lastname: Okur
authors.forename: Selin
authors.initials: S
authors.lastname: Aytac
authors.forename: Mualla
authors.initials: M
authors.lastname: Cetin
authors.forename: Fatma
authors.initials: F
authors.lastname: Gumruk
authors.forename: Seza
authors.initials: S
authors.lastname: Ozen
authors.forename: Aytemiz
authors.initials: A
authors.lastname: Gurgey
mesh_terms: D001171:Arthritis, Juvenile / Q000150:complications / Q000235:genetics* / Q000503:physiopathology; D002675:Child, Preschool; D005260:Female; D006801:Humans; D055501:Macrophage Activation Syndrome / Q000209:etiology / Q000235:genetics* / Q000503:physiopathology; D009154:Mutation; D054353:Perforin / Q000235:genetics*
chemical_list: D054353:Perforin