Q-fever is a zoonosis caused by Coxiella burnetii, an intracellular bacterium. Since the epidemic outbreak of acute Q-fever in Holland nearly 4030 people have been registered with the acute form of the disease. Knowing that only 40% of all infected people develop symptoms, the number of infected people (and potential candidates for chronic Q-fever) are much higher. Chronic Q-fever generally manifest itself after a couple of months or years after the primary infection (in 1-5% of all cases). The clinical presentation can be a life-threatening and frequently underdiagnosed disease, as endocarditis, infected aneurysm and vascular prosthesis or chronic Q-fever related to pregnancy and immunecompromised patients. That's why a screening program is started in the endemic area and trace patients with chronic Q-fever. So eventually, a greater group of patients with chronic vascular Q-fever can be described. In addition, there is still no therapeutic guideline for management of chronic Q-fever in patient with a vascular chronic Q-fever.

Patients with an aneurysm or vascular graft will be screened for chronic Q-fever. Patients with chronic Q-fever will be included in a follow-up program, in which additional research and treatment will start. The initial treatment of patients with chronic Q-fever is doxycycline and hydroxychloroquine for at least 18 months. In addition, patients will be monitored in 3-monthly controls, blood samples and imaging will be done. Parameters as complaints, titers, circulating DNA, grow of aneurysm, complications etc. will be investigated.

Ultimately, the current therapeutic guideline for management of C. burnetii will be evaluated if it can also be applied for patients with vascular chronic Q-fever.

Study design:

Prospective observational survey

Domain:

Patients with an abdominal aneurysm or central vascular reconstruction in an endemic area after an outbreak of acute Q-fever.

Data collection:

In Jeroen Bosch Hospital and Bernhoven Hospital all patients with an aneurysm or central vascular reconstruction will be screened for Q-fever. Other hospitals in Holland will only check for Q-fever, if they suspect a patient of having an infected aneurysm or prosthesis.

A patient with chronic Q-fever will enter a multidisciplinary follow-up program. First, a PET/CT-scan will be provided (question; signs of an infected aneurysm/prosthesis)and chronic Q-fever endocarditis will be excluded. The patients will initially be treated with doxycycline 2 dd 100mg and plaquenil 200mg 3dd for at least 18 months. A 3-monthly follow-up will start, in which bloodsample, ultrasounds and PET/CTscan will be performed. Data will be collected in SPSS for analyses.

Definitions; Past resolved Q-fever: Any IgG phase 2 and IgG phase 1 <1:1024 Chronic Q-fever: IgG phase 1 >= 1:1024

Inclusion Criteria:

• Patients with an aneurysm of the abdominal aorta or iliac arteries of any size.
• Patients with a central vascular reconstruction, such as EVAR, aortic graft and bifurcation graft.

Exclusion Criteria:

- Patients with a recent central vascular reconstruction (after 1-1-2010) due to a stenoses or occlusion

This cohort will be selected from patients with an abdominal aortic disease living in an endemic area after an outbreak of acute Q-fever.