Severe Fever With Thrombocytopenia Syndrome, AKI, and Mortality

Severe fever with thrombocytopenia syndrome (SFTS) is becoming more common across East Asia, with a prevalence of 14% to 36%. This tickborne virus carries a mortality risk and seems to be associated with renal damage. However, little research has focused on risk factors for and clinical outcomes of acute kidney injury in patients with SFTS. Jin Mi Lee and colleagues sought to fill this gap with a study published in Scientific Reports.

The retrospective cohort study included laboratory data and medical information (including comorbidities, complications, and mortality) of 53 patients diagnosed with SFTS virus infection at Kangwon National University Hospital in South Korea between 2016 and 2020. The average patient age was 66.5 years and 29 (54.7%) were male.

The researchers compared baseline characteristics, clinical features, laboratory factors, and mortality rates of patients with and without AKI. They compared survival of the AKI and non-AKI groups using the Kaplan-Meier method. They also used Cox regression analysis to identify the independent risk factors for in-hospital mortality in patients with SFTS and to identify the population with poor prognosis.

In total, nine (15.1%) patients died of SFTS, and 27 (50.9%) patients experienced AKI. The average time from onset of fever to AKI was 3.6 days, and 24 (88.9%) patients developed AKI within the first week of fever onset. Patients in the AKI group were older than those in the non-AKI group, had a higher prevalence of diabetes, and had a significantly higher mortality rate (29.6% vs 3.8%).

Patients with stages 2 or 3 AKI had a 50% mortality rate compared to those with stage 1, whose mortality rate was 17.6%. Mortality rates were significantly higher for patients with AKI compared to those without AKI (P=.017), according to Kaplan-Meier curves. Cox regression analysis found that elevated serum creatinine levels and leukopenia were significant risk factors for mortality.

The authors concluded, “Taken together, our findings highlight the high incidence of AKI in patients with SFTS and underscore its pivotal role as an early prognostic indicator of AKI severity.”

Source: Scientific Reports