Hemophagocytic Lymphohistiocytosis in Children

To study the profile of children with Hemophagocytic Lymphohistiocytosis (HLH) in a tertiary care hospital for children.

A retrospective analysis of case records of 52 children diagnossed with HLH was performed.

Of the 52 children 13% (n = 7) had Familial HLH and 87% (n = 45) had secondary HLH (sHLH). Common manifestations were fever (100%), organomegaly (87%), respiratory distress (54%), neurological symptoms (31%) and skin rashes (26.2%). Anemia and thrombocytopenia were present in 51% and 73% respectively. Hyperferritinemia was present in 96% and hypofibrinogenemia in 42% and high lactate dehydrogenase (LDH) in 91%. Bone marrow examination showed hemophagocytosis in 80%. Most common etiology among infections was viral infections (67%), of which Dengue was the most common (52%). Among children with sHLH 51% received supportive care only. Thirty-seven percent (n = 17) received intravenous (IV) immunoglobulin and steroids. Of these 77% (n = 35) recovered completely. Children with familial HLH were initiated on HLH 2004 protocol but all of them expired due to disease progression.

Identifying HLH early and managing it, poses a significant challenge. Prompt recognition and initiation of immunosuppressive therapy is extremely important for the better outcome; hence high clinical suspicion and structured work up including immunological, and genetic studies is required. It may be difficult to differentiate primary and secondary HLH in many instances unless genetic analysis is done. Identification of familial HLH is necessary for early referral to Hematopoietic Stem Cell Transplantation (HSCT). Hence screening for primary HLH needs to be considered in all children with HLH.