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Deadly case of Pasteurella multocida aortitis and mycotic aneurysm following a cat bite
Dennis Dane Cho1, Yaniv Berliner1, David Carr1
1Dennis Dane Cho, Yaniv Berliner, David Carr, Division of Emergency Medicine, Department of Medicine, University of Toronto, Toronto, ON M4N 3M5, Canada.
Abstract:
Animal bites are frequently encountered in the emergency department (ED). Aortitis leading to mycotic abdominal aortic aneurysm is a rare and potentially deadly complication of Pasteurella multocida (P. multocida) following an animal bite. We present the case of a 68-year-old male who presented to the ED after falling at home. He complained of weakness and abdominal pain. He was in septic shock and was treated empirically with broad-spectrum antibiotics and intravenous fluids. He reported previous antibiotic treatment of a cellulitis secondary to a cat bite injury to his right thumb four weeks prior. Abdominal ultrasound and subsequent computed tomography scan revealed a leaking mycotic abdominal aneurysm that was surgically repaired. Blood cultures and aortic wall tissue cultures grew P. multocida. Given how common animal bite presentations are in the ED, this case highlights the need to consider aortitis and mycotic abdominal aortic aneurysm in an unwell patient with an animal bite.
Insights
A cat bite led to a rare, deadly complication: a mycotic abdominal aortic aneurysm caused by Pasteurella multocida. This case emphasizes considering this severe infection in patients with animal bites presenting with abdominal pain and shock.
Area of Science:
- Infectious Diseases
- Vascular Surgery
- Emergency Medicine
Background:
- Animal bites are common in emergency departments.
- Mycotic abdominal aortic aneurysms are rare but life-threatening complications.
- Pasteurella multocida is a common pathogen associated with animal bites.
Observation:
- A 68-year-old male presented with weakness and abdominal pain, progressing to septic shock.
- He had a recent cat bite treated for cellulitis four weeks prior.
- Imaging revealed a leaking mycotic abdominal aortic aneurysm.
Findings:
- Blood and aortic tissue cultures confirmed Pasteurella multocida infection.
- The mycotic abdominal aortic aneurysm was successfully surgically repaired.
- The patient's septic shock was managed with antibiotics and fluids.
Implications:
- This case highlights the critical need for emergency physicians to consider aortitis and mycotic aneurysms in patients with animal bites, especially those presenting with systemic illness.
- Early recognition and management are crucial for improving outcomes in these rare but severe cases.
- Reinforces the importance of thorough patient history, including recent animal exposures, in the ED setting.
