Abstract:

Objective

To investigatethe clinical characteristics of local cases of severe fever with thrombocytopenia syndrome (SFTS) in Beijing.

Methods

The general condition, epidemiology, clinical symptoms and laboratory indicators of indigenous patients with SFTS admitted to Beijing Ditan Hospital,Capital Medical University from January 2023 to December 2024 were analyzed, retrospectively.

Results

Total of 15 local patients with severe fever complicated with thrombocytopenia syndrome (SFTS) were admitted, comprising 8 males and 7 females.Among these patients, 12 cases recovered, while 3 cases unfortunately died.In 2023, 6 patients were admitted, and all of them recovered.In 2024, 9 patients were admitted, 3 cases of whom died.The average age was (61.0 ± 8.7) years old.The onset of the disease was concentrated from May to September.The main residence areas for the patients included Pinggu, Tongzhou and Mentougou Districts, with 80% (12 cases) being farmers.Three patients (20%) had a clear history of being bitten by ticks, while 4 patients (26.6%) had contact with pet dogs that had been bitten by ticks and 2 patients (13.3%) had contact with sick camels.Among the patients who recovered, 50% (6 cases) had no underlying health conditions, all 3 dead patients had cardiovascular diseases.All 15 patients experienced fever and fatigue, and 73.3% (11 cases) reported digestive symptoms, while 53.3% (8 cases) underwent muscle pain.All 3 dead patients exhibited apparent neurological abnormalities, with 2 of them (66.7%) also showing signs of bleeding.The white blood cell (WBC) ranged (1.0-3.0) × 10⁹/L, one case with the WBC count deceased to 0.9 × 10⁹/L.All patients exhibited thrombocytopenia, and the platelet (PLT) count of 2 patients were less than 30 × 10⁹/L.Additionally, all 15 patients showed varying degrees of organ damage； the urine protein levels of the 3 dead patients ranged from 3+ to 4+, and all had urine occult blood at 3+.The creatinine (Cr) and blood urea nitrogen (BUN) levels were signiflcantly elevated in 2 dead patients.Furthermore, all 15 patients displayed coagulation dysfunction, primarily indicated by elevated D-dimer levels.

Conclusions

The local cases in Beijing were mainly middle-old farmer patients, with the onset of disease from May to September.Their residence was concentrated in the peripheral areas of Beijing.Some patients were in contact with infected animals, such as domestic pet dogs.Patients with old age, cardiovascular underlying disease, abnormal neurological manifestations, bleeding tendency and severe renal impairment may have a poor prognosis.

Key words: Severe fever with thrombocytopenia syndrome, Local cases, Beijing, Clinical characteristics