Hemophagocytic lymphohistiocytosis: a case series of a Brazilian institution

OBJECTIVE To describe the clinical and laboratory presentation of hemophagocytic lymphohistiocytosis in children treated at a referral institution. METHODS A retrospective descriptive study was carried out of seven children diagnosed with hemophagocytic lymphohistiocytosis between 2010 and 2012. The criteria for diagnosis were those proposed by the Histiocyte Society. When indicated, immunochemotherapy was prescribed according to the HLH94 and HLH2004 protocols of the Histiocyte Society. RESULTS The patients' ages at diagnosis ranged from one month to nine years. All patients had splenomegaly, fever, anemia, thrombocytopenia, hyperferritinemia and hypertriglyceridemia. Bone marrow hemophagocytosis was detected in six patients. In six cases, infectious diseases triggered the syndrome. In two cases, associated with visceral leishmaniasis, remission was achieved after treatment of the underlying infection. Three patients, who had Epstein-Barr-related hemophagocytic lymphohistiocytosis, required treatment with immunochemotherapy. They are alive and in remission; one patient had symptoms of juvenile rheumatoid arthritis and another, who was suspected of having primary hemophagocytic lymphohistiocytosis, entered into remission after bone marrow transplantation. Two deaths (28.6%) occurred in patients with suspected primary hemophagocytic lymphohistiocytosis; one whose clinical picture was triggered by cytomegalovirus infection did not respond to immunochemotherapy and the other died before any specific treatment was provided. CONCLUSION As reported before, hemophagocytic lymphohistiocytosis has a multifaceted presentation with nonspecific signs and symptoms. In secondary forms, remission may be achieved by treating the underlying disease. In the primary forms, remission may be achieved with immunochemotherapy, but bone marrow transplantation is required for cure.