Manifestations and Myocarditis in Hospitalized Adults with Scrub Typhus: A Prospective Cohort Study from South India

Abstract

Background: Scrub typhus is an important cause of acute febrile illness in South India and may produce cardiovascular involvement through endothelial injury, vasculitis and systemic inflammation. However, the burden and clinical impact of myocarditis in adult scrub typhus remain insufficiently characterized.

Materials and Methods: This prospective cohort study included 50 hospitalized adults with confirmed scrub typhus in a tertiary care centre in South India. Demographic details, clinical features, laboratory parameters, illness severity scores, electrocardiographic findings, cardiac biomarkers, echocardiographic parameters, treatment requirements and outcomes were recorded. Myocardial injury was defined by elevated troponin T, while myocarditis was presumed when myocardial injury was associated with global left ventricular systolic dysfunction.

Results: The mean age was 49.41 ± 16.1 years, with female predominance. Fever was universal, breathlessness occurred in 64%, and eschar was present in 40%. The cohort had severe systemic illness, with ICU admission in 60%, ventilatory support in 60%, vasoactive support in 56%, and mortality of 10%. Myocardial injury was observed in 31 patients (62%), myocardial dysfunction in 15 (30%), myocarditis in 11 (22%), diastolic dysfunction in 11 (22%), and pericardial involvement in 26 (52%). Patients with myocarditis had higher SOFA scores, more cardiovascular failure, greater inotropic and ventilatory requirement, and longer hospital stay. Mortality was comparable between groups.

Conclusion: Cardiac involvement is common in hospitalized scrub typhus. Systematic assessment with cardiac biomarkers and bedside echocardiography is useful, especially in patients with shock, respiratory failure or high SOFA score.