Imaging of aneurysm-associated vertebral erosion and Coxiella burnetii vascular infection: a multimodality imaging review.

Destructive spinal change that directly abuts an aneurysm or vascular graft should first be read as a vascular sign. The key distinction is noninfectious chronic contained rupture, in which pulsatile pressure or contained hematoma causes smooth vertebral scalloping, versus infected aneurysm or graft, in which contiguous spread produces osteomyelitis or spondylodiscitis. Coxiella burnetii is an important cause of the latter because chronic Q fever can produce indolent, culture-negative vascular infection with adjacent spinal extension. Reported Q fever vertebral osteomyelitis frequently coexists with aneurysmal disease, including 23 of 34 cases (68%) in one review and 24 of 39 cases (62%) in a pooled analysis. This review emphasizes that diagnostic sequence. CTA defines aneurysm morphology, rupture risk, periaortic inflammation, and graft involvement; MRI defines marrow, disc, paravertebral, foraminal, and epidural extension; and FDG-PET/CT is valuable in chronic Q fever because it detects low-grade vascular and osseous inflammation. Indium-111 leukocyte scintigraphy may be less conspicuous in chronic, macrophage-predominant, non-pyogenic infection. An illustrative case shows thoracoabdominal aneurysm-associated T11 erosion in suspected Q fever vascular infection. Recognizing this vascular-spinal pattern can prevent misdiagnosis, guide timely antimicrobial and operative planning, and support follow-up assessment.