Macrophage activation syndrome as part of systemic juvenile idiopathic arthritis: diagnosis, genetics, pathophysiology and treatment

Genes Immun. 2012 Jun;13(4):289-98. doi: 10.1038/gene.2012.3. Epub 2012 Mar 15.

Abstract

Macrophage activation syndrome (MAS) is a severe, frequently fatal complication of systemic juvenile idiopathic arthritis (sJIA) with features of hemophagocytosis leading to coagulopathy, pancytopenia, and liver and central nervous system dysfunction. MAS is overt in 10% of children with sJIA but occurs subclinically in another 30-40%. It is difficult to distinguish sJIA disease flare from MAS. Development of criteria for establishing MAS as part of sJIA are under way and will hopefully prove sensitive and specific. Mutations in cytolytic pathway genes are increasingly being recognized in children who develop MAS as part of sJIA. Identification of these mutations may someday assist in MAS diagnosis. Defects in cytolytic genes have provided murine models of MAS to study pathophysiology and treatment. Recently, the first mouse model of MAS not requiring infection but rather dependent on repeated stimulation through Toll-like receptors was reported. This provides a model of MAS that may more accurately reflect MAS pathology in the setting of autoinflammation or autoimmunity. This model confirms the importance of a balance between pro- and anti-inflammatory cytokines. There has been remarkable progress in the use of anti-pro-inflammatory cytokine therapy, particularly against interleukin-1, in the treatment of secondary forms of MAS, such as in sJIA.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Adrenal Cortex Hormones / pharmacology
  • Animals
  • Antirheumatic Agents / pharmacology
  • Arthritis, Juvenile / genetics
  • Arthritis, Juvenile / immunology
  • Arthritis, Juvenile / physiopathology*
  • Child
  • Cyclosporine / pharmacology
  • Disease Models, Animal
  • Humans
  • Interleukin 1 Receptor Antagonist Protein / pharmacology
  • Macrophage Activation Syndrome / diagnosis*
  • Macrophage Activation Syndrome / drug therapy*
  • Macrophage Activation Syndrome / genetics*
  • Macrophage Activation Syndrome / immunology
  • Macrophage Activation Syndrome / physiopathology*
  • Mice
  • Mutation
  • Receptors, Interleukin-1 / antagonists & inhibitors
  • Receptors, Interleukin-1 / drug effects
  • Receptors, Interleukin-1 / immunology
  • Receptors, Interleukin-10 / antagonists & inhibitors
  • Receptors, Interleukin-10 / immunology
  • Toll-Like Receptor 9 / immunology

Substances

  • Adrenal Cortex Hormones
  • Antirheumatic Agents
  • Interleukin 1 Receptor Antagonist Protein
  • Receptors, Interleukin-1
  • Receptors, Interleukin-10
  • Toll-Like Receptor 9
  • Cyclosporine