Nationwide survey of hemophagocytic lymphohistiocytosis in Japan

Int J Hematol. 2007 Jul;86(1):58-65. doi: 10.1532/IJH97.07012.

Abstract

Hemophagocytic lymphohistiocytosis (HLH), a disorder of the mononuclear phagocyte system, can be classified into two distinct forms: primary HLH (FHL) and secondary HLH. To clarify the epidemiology and clinical outcome for each HLH subtype, we conducted a nationwide survey of HLH in Japan. Since 799 patients were diagnosed in 292 institutions of Japan between 2001 and 2005, the annual incidence of HLH was estimated as 1 in 800,000 per year. Among them, 567 cases were actually analyzed in this study. The most frequent subtype was Epstein-Barr virus (EBV)-associated HLH, followed by other infection- or lymphoma-associated HLH. Age distribution showed a peak of autoimmune disease- and infection-associated HLH in children, while FHL and lymphoma-associated HLH occurred almost exclusively in infants and the elderly, respectively. The 5-year overall survival rate exceeded 80% for patients with EBV- or other infection-associated HLH, was intermediate for those with FHL or B-cell lymphoma-associated HLH, and poor for those with T/NK cell lymphoma-associated HLH (<15%). Although this nationwide survey establishes the heterogeneous characteristics of HLH, the results should be useful in planning prospective studies to identify the most effective therapy for each HLH subtype.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Age Factors
  • Autoimmune Diseases
  • Child
  • Child, Preschool
  • Epstein-Barr Virus Infections / complications
  • Epstein-Barr Virus Infections / epidemiology*
  • Female
  • Health
  • Humans
  • Infant
  • Japan / epidemiology
  • Lymphohistiocytosis, Hemophagocytic / complications
  • Lymphohistiocytosis, Hemophagocytic / epidemiology*
  • Lymphohistiocytosis, Hemophagocytic / virology
  • Lymphoma, B-Cell / complications*
  • Lymphoma, B-Cell / epidemiology
  • Male
  • Middle Aged
  • Survival Analysis