Cat Bite Leading to Thoracic Aortic Endograft Infection and Fatal Haemoptysis

Thoracic aortic graft infection is a rare but life-threatening complication of aortic repair, associated with high mortality due to sepsis, aortic rupture and fistulisation. Typical causative bacteria include Staphylococcus spp., Enterobacteriaceae and Pseudomonas spp. However, atypical microorganisms may be implicated. A 53-year-old patient with a history of thoracic aortic endovascular repair following dissection presented with fever, cough and dyspnoea, initially attributed to non-specific viral illness that led to discharge. Blood cultures later grew Capnocytophaga canimorsus. Subsequent history revealed a recent cat bite, and a fluorine-18 -fluorodeoxyglucose positron emission tomography scan suggested thoracic aortic graft infection. Despite antibiotic therapy and endovascular intervention following a single episode of haemoptysis, fatal haemoptysis occurred. This case highlights the potential for a minor cat bite to cause bacteraemia and catastrophic vascular graft infection. Thorough evaluation, including animal exposure history, and a high index of clinical suspicion are essential in patients with aortic grafts presenting with an infection of unclear origin.

Aortic graft infections carry a high risk of a fatal outcome, making early identification and multidisciplinary management critical.Early fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography scan should be considered when aortic graft infection is suspected despite inconclusive initial imaging.Capnocytophaga canimorsus bacteraemia following a cat bite can cause life-threatening infections, even in immunocompetent patients.