ABSTRACT
Background: this Syndrom is rare, but aggressive and potentially life-threatening disease most often affects infants from birth to 18 months of age, but cases in older children and adults have been reported
Materials and Methods: cases Report Study in Masih daneshvary Hospital.All related records in this regard were collected from late year
Result: superiority of sexual[Men] and low mortality rate
Conclusions: because HLH is often fatal, one must have a high index of suspicion that patients who present with several of the following: high fevers, maculopapular rash, failure to thrive, central nervous system symptoms, hepatosplenomegaly, lymphadenopathy, cytopenias, coagulopathy, abnormal liver function tests, and high serum ferritin, Sudden decrease of ESR, may have HLH