A Case of Severe Fever With Thrombocytopenia Syndrome Accompanied by Self-Limiting Severe Proteinuria That Inversely Correlated With the Platelet Count

Abstract

We herein present a case of a 68-year-old man who was referred to our hospital for a tick bite accompanied by fever and general malaise. He exhibited typical clinical symptoms such as abdominal pain, diarrhea, and vomiting during hospitalization. A laboratory examination showed progressive thrombocytopenia and leukopenia during the early part of hospitalization. A definite diagnosis of severe fever with thrombocytopenia syndrome (SFTS) was made by a reverse transcription polymerase chain reaction (RT-PCR) from his blood sample in the Tokushima Prefectural Public Health Institute. Proteinuria is generally detected in more than half of patients with SFTS. In the present case, the clinical course showed a clear inverse correlation between self-limiting severe proteinuria and the platelet count during hospitalization. Although it is not currently clear how immunological interactions among the virus, platelets, and immunoglobulins affect the glomerulus or cause proteinuria, our results may contribute to elucidating the pathogenic mechanism of SFTS-associated glomerulonephritis. To the best of our knowledge, this case report is the first to show an inverse correlation between proteinuria and the platelet count in a patient with SFTS.