Chronic Q fever-related complications and mortality: data from a nationwide cohort

Clin Microbiol Infect. 2019 Nov;25(11):1390-1398. doi: 10.1016/j.cmi.2018.11.023. Epub 2018 Dec 10.

Abstract

Objectives: Chronic infection with Coxiella burnetii (chronic Q fever) can cause life-threatening conditions such as endocarditis, infected vascular prostheses, and infected arterial aneurysms. We aimed to assess prognosis of chronic Q fever patients in terms of complications and mortality.

Methods: A large cohort of chronic Q fever patients was assessed to describe complications, overall mortality and chronic Q fever-related mortality. Chronic Q fever-related mortality was expressed as a case fatality rate (number of chronic Q fever-related deaths/number of chronic Q fever patients).

Results: Complications occurred in 166 of 439 (38%) chronic Q fever patients: in 61% of proven (153/249), 15% of probable (11/74), and 2% of possible chronic Q fever patients (2/116). Most frequently observed complications were acute aneurysms (14%), heart failure (13%), and non-cardiac abscesses (10%). Overall mortality was 38% (94/249) for proven chronic Q fever patients (median follow-up 3.6 years) and 22% (16/74) for probable chronic Q fever patients (median follow-up 4.7 years). The case fatality rate was 25% for proven (63/249) chronic Q fever patients and 4% for probable (3/74) chronic Q fever patients. Overall survival was significantly lower in patients with complications, compared to those without complications (p <0.001).

Conclusions: In chronic Q fever patients, complications occur frequently and contribute to the mortality rate. Patients with proven chronic Q fever have the highest risk of complications and chronic Q fever-related mortality. Prognosis for patients with possible chronic Q fever is favourable in terms of complications and mortality.

Keywords: Complications; Coxiella burnetii; Endocarditis; Infected vascular prosthesis; Mortality; Mycotic aneurysm; Q fever.

MeSH terms

  • Abscess / epidemiology*
  • Abscess / mortality
  • Adolescent
  • Adult
  • Aged
  • Aneurysm, Infected / epidemiology*
  • Aneurysm, Infected / mortality
  • Cohort Studies
  • Endocarditis / epidemiology*
  • Endocarditis / mortality
  • Female
  • Humans
  • Male
  • Middle Aged
  • Prosthesis-Related Infections / epidemiology*
  • Prosthesis-Related Infections / mortality
  • Q Fever / complications*
  • Q Fever / mortality*
  • Survival Analysis
  • Young Adult