Pathogen spectrum, clinical traits and exploration of mortality outcome-improving medication regimens in coinfection patients with severe fever with thrombocytopenia syndrome: a multicenter cohort study.

PURPOSE: Using a multicenter clinical data, this study aimed to systematically analyze the clinical characteristics, pathogen spectrum, and independent risk/protective factors for coinfection in SFTS patients; additionally, it sought to explore optimal therapeutic regimens to reduce the case fatality rate of SFTS patients with coinfection.

METHODS

Clinical data of 1,675 patients with SFTS who were hospitalized for the first time, collected from 6 institutions between May 2011 and November 2024, were included and analyzed.

RESULTS

The coinfection group had a significantly higher case fatality rate (24.3% vs. 6.7%, P < 0.001), with the mixed bacterial-fungal infection subgroup showing the highest mortality risk (Log-rank test, P < 0.001). Albumin served as a protective factor against coinfection, with a cutoff value of 32 g/L identified; administering human albumin at this threshold could partially reduce the coinfection rate. Furthermore, on the basis of this protective effect of albumin, the combination of human albumin and corticosteroids was associated with a trend toward improved prognostic survival in coinfected patients.

CONCLUSION

This study found a high proportion of SFTS patients with coinfection, which significantly worsens their clinical prognosis. SFTS currently has no specific therapy; clinical treatment focuses on symptomatic and supportive care, with strict standardization for antibiotics and antifungal use, and attention to patients' nutritional support. Albumin is a key protective factor associated with a lower risk of coinfection in SFTS patients; combined use of human albumin and corticosteroids was associated with a further trend toward better clinical prognosis in coinfected patients.