Clinical Research Directory

China Aortic Infection and Graft Infection Study: An Ambispective Cohort

Vascular infections are uncommon but severe infections involving the arterial wall, vascular grafts, or endografts, and their diagnosis and management remain challenging. The CAIGIS Cohort is an ambispective observational cohort established at Zhongshan Hospital, Fudan University, to create an integrated clinical research platform and biobank for patients with suspected or confirmed vascular infections. The primary research focus is the diagnosis and characterization of causative pathogens. Conventional microbiological methods and emerging molecular diagnostic technologies will be systematically evaluated, with particular emphasis on blood-based pathogen detection as a form of liquid biopsy and its diagnostic value compared with local tissue or operative specimens. Serial blood samples and tissue specimens, when available, will also be used to investigate biomarkers associated with treatment response and clinical outcomes. Another major focus is the role of molecular imaging, particularly 18F-FDG PET/CT, in the diagnosis and longitudinal assessment of vascular infections. The study will evaluate its diagnostic performance, its added value in patients with inconclusive conventional imaging, and the potential significance of changes in metabolic activity during follow-up for assessing treatment response, residual infection, recurrence, and prognosis. The cohort will further support nested translational studies addressing specific pathogen- and disease-related questions. These include longitudinal characterization of microbial communities in patients with vascular-enteric fistulas; evaluation of the clinical significance and invasive potential of Candida species; investigation of the clinical and biological characteristics of mycobacterial vascular infections; and exploration of pathogen-host interactions within infected vascular tissues. By integrating longitudinal clinical data, microbiological results, molecular diagnostics, PET/CT findings, treatment information, outcomes, and biospecimens, the cohort aims to improve etiological diagnosis, disease stratification, treatment monitoring, prognostic assessment, and understanding of the pathogenesis of vascular infections.