Bone marrow findings in severe fever with thrombocytopenia syndrome: prominent haemophagocytosis and its implication in haemophagocytic lymphohistiocytosis
- Namhee Kim1,
- Kye-Hyung Kim2,3,
- Su Jin Lee4,
- Sang-Hyuk Park1,
- In-Suk Kim1,
- Eun Yup Lee1,
- Jongyoun Yi1,3
- 1Department of Laboratory Medicine, Pusan National University School of Medicine, Busan, South Korea
- 2Department of Internal Medicine, Pusan National University Hospital, Busan, South Korea
- 3Biomedical Research Institute, Pusan National University Hospital, Busan, South Korea
- 4Department of Internal Medicine, Pusan National University Yangsan Hospital, Yangsan, Gyeongsangnam-do, South Korea
- Correspondence to Professor J Yi, Department of Laboratory Medicine, Pusan National University School of Medicine, 179 Gudeok-ro, Seo-gu, Busan 49241, South Korea;
- Received 24 September 2015
- Accepted 21 October 2015
- Published Online First 16 November 2015
Aims Severe fever with thrombocytopenia syndrome (SFTS) is an emerging tick-borne disease caused by the SFTS virus; primary manifestations are fever, thrombocytopenia, leukopenia and gastrointestinal symptoms. Before an aetiological diagnosis is made, SFTS patients can undergo bone marrow examination due to cytopenias. Although several studies have reported on bone marrow examination in SFTS patients, most do not provide adequate details. Bone marrow findings in SFTS patients were investigated in this study.
Methods An observational study was conducted in SFTS patients who were hospitalised between 2013 and 2014 in two university hospitals in South Korea. Patients were included in the study if SFTS was confirmed by real-time PCR for the SFTS virus and a bone marrow examination was conducted. The morphologic findings of the bone marrow samples were reviewed.
Results Three cases met the study inclusion criteria. One patient died of multiple organ failure. Haemophagocytosis was evident in the bone marrow samples of all three patients. Histiocytic hyperplasia and haemophagocytosis were more pronounced in the fatal case. One patient was diagnosed as having haemophagocytic lymphohistiocytosis.
Conclusions Haemophagocytosis in the bone marrow of SFTS patients may be common. In SFTS endemic areas, SFTS should be one of the differential diagnoses of fever of unknown origin with haemophagocytosis in the bone marrow.