Prolonged fever and pancytopenia in a case of severe dengue may be secondary hemophagocytic lymphohistiocytosis.

The diagnosis of secondary hemophagocytic lymphohistiocytosis (HLH) in the setting of dengue fever is usually challenging but should be kept in mind in patients with persistent fever, pancytopenia, and multiorgan dysfunction. We report a case of severe dengue who had prolonged fever with multiorgan involvement, laboratory features fulfilling the diagnostic criteria of HLH, and had a prompt response with high-dose corticosteroids. Physicians should be aware of this rare clinical syndrome and its variable clinical presentations so that fatal outcomes can be prevented with prompt and appropriate treatment.