Hemophagocytic Lymphohistiocytosis: An Unusual Presentation of Scrub Typhus.

Scrub typhus is an important etiological cause for acute undifferentiated febrile illness in the Asia-Pacific region, including Sri Lanka. It is a mite-borne disease caused by Orientia tsutsugamushi. Hemophagocytic lymphohistiocytosis (HLH) is a rapidly progressive and potentially life-threatening hyperinflammatory syndrome rarely associated with scrub typhus. We herein describe a rare case of scrub typhus complicated by hemophagocytic lymphohistiocytosis in a 40-year-old previously healthy woman who presented with a history of an acute febrile illness. Following the observation of acute deterioration of hematological parameters despite the nature of the febrile illness, the rare association of hemophagocytic lymphohistiocytosis was considered, and this disease association was confirmed by fulfilling six out of eight of the diagnostic criteria of haemophagocytic lymphohistiocytosis. The patient made an uneventful recovery following treatment for the precipitating illness and with supportive care.