Clinical characteristics and outcomes of acute Q fever with and without hepatitis: a retrospective cohort study.

Background: Hepatitis is a variably reported manifestation of acute Q fever; however, its clinical implications remain unclear. This study investigates whether hepatitis is associated with distinct clinical features and outcomes compared to cases without hepatitis.

Methods: Data from a retrospective, single-centre study of adult patients diagnosed with acute Q fever between January 2018 and December 2023 were analysed. Patients with clinical and laboratory evidence of acute infection, defined by positive phase II IgG serology or Coxiella burnetii RT-PCR were included. Patients were categorised into two groups based on the presence or absence of hepatitis, defined as elevated liver transaminases above the upper normal limit. Descriptive comparisons were conducted between the two groups.

Results: 116 patients were included, 87 in the hepatitis group and 29 in the non-hepatitis group. The hepatitis group showed a male predominance (66.7%), while the non-hepatitis group had a higher proportion of females (55.2%) (p = 0.03). Fever was more common in the hepatitis group (85.1%) compared to the non-hepatitis group (65.5%) (p = 0.02). A confirmed diagnosis was more frequent in the hepatitis group (62.1% vs. 27.6%) (p < 0.001). A greater proportion of patients in the hepatitis group received appropriate antibiotic treatment (79.3% vs. 44.8%), with earlier initiation. Despite these differences, complication rates were comparable between groups, and no in-hospital mortality was observed.

Conclusion: Hepatitis is a common manifestation of acute Q fever and is associated with a higher likelihood of confirmed diagnosis and earlier initiation of appropriate antibiotic treatment. Clinical outcomes remain favourable, even in patients with hepatitis.