Clinical and laboratory factors associated with scrub typhus and hemorrhagic fever with renal syndrome in Southwestern Korea: A cross-sectional study.

BACKGROUND

Scrub typhus and Hemorrhagic fever with renal syndrome (HFRS) are prevalent infectious diseases in South Korea. This study compared the clinical and laboratory characteristics associated with scrub typhus and HFRS treated at Chosun University Hospital, South Korea.

METHOD/FINDINGS: A retrospective cross-sectional study was conducted by reviewing the medical records of patients diagnosed with scrub typhus and HFRS between 2010 and 2023. Diagnoses were confirmed through molecular and serological testing. A total of 156 patients with scrub typhus and 45 patients with HFRS were included. Among patients with scrub typhus, 136 (87.18%) patients had Boryong strain, 4 (2.56%) had Taguchi strain, 3 (1.93%) had Karp strain, and 1 (0.64%) had Kanda strain. Most cases of scrub typhus and HFRS occurred in individuals aged ≥65 years. The common clinical features of scrub typhus included fever, fatigue, skin rash, and eschar. In contrast, HFRS commonly presented with fever, gastrointestinal symptoms, and hemorrhagic manifestations. The mean hospital stay was significantly longer for HFRS (14.09 ± 7.67 days) compared to scrub typhus (7.89 ± 7.56 days, p < 0.001). A higher proportion of patients with HFRS (15, 33.33%) required intensive care unit admission compared to patients with scrub typhus (14, 8.97%, p < 0.001). Among patients with scrub typhus, the adjusted odds of presenting with a skin rash, eschar, or lymphopenia (<1500/µL) were 1.37 (95% confidence interval [CI]: 1.18-1.59, p < 0.001), 1.25 (95% CI: 1.11-1.40, p < 0.001), and 1.83 (95% CI: 1.34-2.49, p < 0.001), respectively.

CONCLUSIONS

While scrub typhus and HFRS share overlapping clinical features, skin rash, eschar, and lymphopenia were more commonly associated with scrub typhus. Further studies are warranted to characterize clinical features and outcomes of various hantavirus subtypes.