Introduction: Mycotic pseudoaneurysms are rare but severe sequelae of an arterial wall infection. If undiagnosed and untreated they can lead to significant morbidity and mortality through complications such as arterial rupture or dissection.
Case report: This report details the case of a 64-year-old-male who developed a left common iliac artery mycotic pseudoaneurysm from Proteus mirabilis, which was associated with a prevertebral abscess. The patient presented with isolated, left lower extremity edema and intermittent fevers. The case is unique in both the pathogen (P mirabilis) and in its association with presumed direct arterial wall infection from an adjacent prevertebral abscess.
Conclusion: The obscure presentation highlights the need for a high clinical suspicion of such a diagnosis when a patient presents with a certain constellation of symptoms and the right predisposing risk factors in their history.