Clinical implications of cardiac involvement in Q fever: Findings from a Spanish cohort

Abstract

Introduction

Q fever is a zoonosis caused by Coxiella burnetii. Spain reports the highest incidence in Europe. Its chronic form may present as infective endocarditis, though other cardiac complications have also been described.

Methods

We conducted a retrospective study of patients admitted for Q fever at a tertiary hospital between 2000 and 2023. Only microbiologically confirmed cases were included. Clinical presentation was analyzed, focusing on patients with cardiac involvement.

Results

A total of 42 patients were included (66.6% male, mean age 49.7 ± 20.6 years); 28 (66.7%) had acute Q fever and 14 (33.3%) chronic. Cardiac involvement was identified in 12 patients (28.5%): 7 with infective endocarditis (all chronic), 3 with myocarditis (2 progressed to dilated cardiomyopathy), and 2 with pericarditis. Overall mortality among patients with cardiac involvement was 25%.

Conclusion

Cardiac manifestations in Q fever may be underdiagnosed. In our cohort, cardiac involvement was frequent and associated with high mortality. Clinicians should maintain a high index of suspicion, especially in chronic Q fever or in patients with fever of unknown origin.