Localizing chronic Q fever: a challenging query

BMC Infectious Diseases

Table 2 Risk factors for developing chronic Q fever in 52 patients with possible, probable and proven chronic Q fever*

	Proven chronic Q fever:	Probable chronic Q fever:	Possible chronic Q fever:
	Number of patients	Number of patients	Number of patients
	(% or range)	(% or range)	(% or range)
Number of patients	18	14	20
Pre-existing valvular disease ^†‡	5 (28%)	4 (29%)	0
Mitral regurgitation	0	2 (14%)	0
Tricuspid regurgitation	0	1 (7%)	0
Bicuspid aortic valve	0	1 (7%)	0
Congenital (not bicuspid aortic valve)	1 (6%)	1 (7%)	0
Rheumatic fever	1 (6%)	0	0
Cardiac valve prosthesis^†	4 (22%)	0	0
Biological aortic prosthesis	3 (17%)	0	0
Biological mitral prosthesis	1 (6%)	0	0
Mechanical aortic prosthesis	1 (6%)	0	0
Known aneurysm	8 (44%)	1 (7%)	0
Abdominal aortic aneurysm	7 (39%)	0	0
Dilated aortic root	1 (6%)	0	0
Cerebral aneurysm	0	1 (7%)	0
Vascular prosthesis	11 (61%)	4 (29%)	0
Abdominal aortic graft	7 (39%)	1 (7%)	0
Thoracic aortic graft	2 (11%)	0	0
PTA, iliacal or renal arteries	1 (6%)	2 (14%)	0
Goretex vascular shunt	1 (6%)	0	0
Coiling of cerebral aneurysm	0	1 (7%)	0
Immunocompromised	1 (6%)	6 (43%)	0
Immunosuppressive therapy	1 (6%)	4 (29%)	0
Myelodysplastic syndrome	0	2 (14%)	0
Co-morbidity ^†	18 (100%)	14 (100%)	8 (40%)
Chronic renal insufficiency	6 (33%)	4 (29%)	1 (5%)
Diabetes	3 (17%)	2 (14%)	4 (20%)
Active malignancy	1 (6%)	4 (29%)	1 (5%)
Systemic sclerosis	1 (6%)	2 (14%)	0
COPD	2 (11%)	3 (21%)	5 (25%)
Other^§	5 (28%)	3 (21%)	3 (15%)

^*Adapted from Wegdam-Blans et al. [15].
^†Multiple predisposing conditions are possible for a patient.
^‡Including cardiac valve prosthesis; valvulopathies were considered clinically significant if ≥ grade II.
^§Including severe peripheral arterial disease, coronary artery bypass graft, congestive heart failure and liver cirrhosis.
Bold texts summarize components of the table.
Abbreviations: PTA Percutaneous transluminal angioplasty, COPD Chronic obstructive pulmonary disease.

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