title: Prognostic factors and outcomes of adults with hemophagocytic lymphohistiocytosis.
abstract: OBJECTIVE
  To describe the prognostic factors and outcomes of adults with hemophagocytic lymphohistiocytosis (HLH), a rare disorder caused by pathologic activation of the immune system.
  
  
  METHODS
  The study population consisted of a consecutive cohort of adult (age ≥18 years) patients treated at Mayo Clinic in Rochester, Minnesota, from January 1, 1996, through December 31, 2011, in whom a diagnosis of HLH was suspected and subsequently confirmed by retrospective review using the HLH-04 diagnostic criteria.
  
  
  RESULTS
  Of 250 adult patients suspected of having HLH, 62 met the HLH-04 diagnostic criteria and were included in the final analysis. The median age was 49 years (range, 18-87 years), and 42 (68%) were male. The underlying cause of HLH was malignant tumor in 32 patients (52%), infection in 21 patients (34%), autoimmune disorder in 5 patients (8%), and idiopathic disease in 4 patients (6%). After a median follow-up of 42 months, 41 patients (66%) had died. The median overall survival of the entire cohort was 2.1 months. The median overall survival of patients with tumor-associated HLH was 1.4 months compared with 22.8 months for patients with non-tumor-associated HLH (P=.01). The presence of a malignant tumor and hypoalbuminemia were significant predictors of inferior survival on multivariate analysis.
  
  
  CONCLUSIONS
  In this large series of adults with secondary HLH treated at a single tertiary care center, patients with low serum albumin levels and tumor-associated HLH had a markedly worse survival. Hemophagocytic lymphohistiocytosis remains elusive and challenging to clinicians who must maintain a high index of suspicion. The recent discovery of several novel diagnostic and therapeutic modalities may improve outcomes of adult patients with HLH.
authors.affiliation: Division of Hematology, Mayo Clinic, Rochester, MN.
authors.forename: Sameer A
authors.initials: SA
authors.lastname: Parikh
authors.affiliation: Division of Hematology, Mayo Clinic, Rochester, MN.
authors.forename: Prashant
authors.initials: P
authors.lastname: Kapoor
authors.affiliation: Division of Hematology, Mayo Clinic, Rochester, MN.
authors.forename: Louis
authors.initials: L
authors.lastname: Letendre
authors.affiliation: Division of Hematology, Mayo Clinic, Rochester, MN.
authors.forename: Shaji
authors.initials: S
authors.lastname: Kumar
authors.affiliation: Division of Hematology, Mayo Clinic, Rochester, MN. Electronic address: wolanskyj.alexandra@mayo.edu.
authors.forename: Alexandra P
authors.initials: AP
authors.lastname: Wolanskyj
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D002423:Cause of Death; D015331:Cohort Studies; D016208:Databases, Factual; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D051359:Lymphohistiocytosis, Hemophagocytic / Q000175:diagnosis* / Q000188:drug therapy / Q000235:genetics / Q000401:mortality*; D008297:Male; D008875:Middle Aged; D015513:Oncogene Proteins / Q000235:genetics; D011379:Prognosis; D016016:Proportional Hazards Models; D035583:Rare Diseases; D012189:Retrospective Studies; D018570:Risk Assessment; D012720:Severity of Illness Index; D016019:Survival Analysis; D055815:Young Adult
chemical_list: D015513:Oncogene Proteins