A case of aortic abscess and acute kidney injury caused by chronic Q fever

Q fever, caused by Coxiella burnetii, is a global zoonosis characterized by acute self-limiting influenza-like syndrome, pneumonia, hepatitis, or chronic infection. We present a rare case of chronic Q fever complicated by an aortic root abscess and acute kidney injury to highlight diagnostic challenges and therapeutic strategies for such complex presentations. Case description : A 62-year-old farmer previously healthy, presented with fever and heart failure which was alleviated with appropriate antimicrobial treatment, but later developed recurrent fever with hematuria and acute kidney injury. Renal biopsy showed diffuse proliferative glomerulonephritis with exudative features. Immunohistochemical analysis and electron microscopy were negative. A usual infection screen and blood culture failed to determine the source of infection. However, a cardioesophageal ultrasound showed the formation of a pus cavity at the root of the ascending aorta. The Polymerase Chain Reaction (PCR) and serology of Coxiella burnetti turned out positive indicative of Q fever infection. Conclusion : Q fever can be complicated by aortic abscess and acute kidney injury. It is rare for chronic Q fever infection to cause major vascular abscess along with acute kidney injury, and the diagnosis and treatment are often more difficult. The combination of molecular detection, imaging and pathology may be necessary to clinch to diagnosis. In patients with recurrent fever accompanied by multiple organ injuries, Q fever should not be neglected in the differentials. Doxycycline is the first-line treatment for Q infection, but the presence of a perivascular abscess may require surgical intervention. In addition, long-term follow-up of renal function and the risk of recurrence of endocarditis is advised.