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Macrophage activation syndrome in children with systemic-onset juvenile chronic arthritis

Shinji Kounami1, Megumi Yoshiyama, Keiko Nakayama

  • 1Departmentof Pediatrics, Wakayama Medical University, Kimiidera, Wakayama City, Japan. nami@mail.wakayama-med.ac.jp

Acta Haematologica
|April 2, 2005
PubMed

Insights

Macrophage activation syndrome (MAS) in children with systemic-onset juvenile chronic arthritis (SOJCA) requires prompt diagnosis. Urinary beta2-microglobulin (beta2MG) is a sensitive indicator, and cyclosporin A (CSP) treatment leads to rapid recovery.

Area of Science:

  • Pediatric Rheumatology
  • Immunology
  • Hematology

Background:

  • Macrophage activation syndrome (MAS) is a severe, life-threatening complication in pediatric rheumatic diseases.
  • Systemic-onset juvenile chronic arthritis (SOJCA) is a primary condition associated with MAS.
  • Early diagnosis and intervention are critical for managing MAS due to its high fatality rate.

Purpose of the Study:

  • To assess the clinical features of MAS in children with SOJCA.
  • To identify sensitive biologic markers for MAS diagnosis.
  • To evaluate the efficacy of cyclosporin A (CSP) in treating MAS.

Main Methods:

  • Retrospective analysis of nine MAS events in five pediatric patients with SOJCA.
  • Monitoring of clinical symptoms including fever, platelet, and white blood cell counts.
  • Measurement of urinary beta2-microglobulin (beta2MG), serum beta2MG, and soluble interleukin-2 receptor levels.

Main Results:

  • MAS diagnosis was indicated by persistent fever and decreased blood cell counts.
  • Elevated urinary beta2MG levels proved to be a sensitive diagnostic marker for MAS.
  • Serum beta2MG and soluble interleukin-2 receptor levels were also elevated, reflecting hyperactivated immunity.
  • Four of five patients treated with cyclosporin A (CSP) showed rapid and complete recovery.
  • One patient not treated with CSP succumbed to respiratory failure.

Conclusions:

  • Urinary beta2MG is a valuable biomarker for early MAS detection in pediatric rheumatic diseases.
  • Cyclosporin A (CSP) demonstrates significant efficacy in treating MAS, leading to rapid clinical improvement.
  • CSP should be considered a first-line therapeutic agent for MAS in children with SOJCA.

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