Ruptured Abdominal Aortic Aneurysm Presenting as Septic Shock

A patient presented to the emergency department with undifferentiated shock 4 days after discharge from a hospitalization for a lower gastrointestinal bleed. The patient fulfilled 4/4 of the Systemic Inflammatory Response Syndrome criteria and 3/3 of the quick Sequential Organ Failure Assessment criteria on presentation to the emergency department, notably, without a localized source of infection and no localizing symptoms. After admission, the patient's hemoglobin was found to have dropped more than expected after intravenous (IV) fluid administration, suggesting a potential alternative or concurrent etiology of the patient's shock state. A digital rectal and focused assessment with sonography in trauma exam were performed and negative. The patient was then diagnosed with a ruptured infrarenal abdominal aortic aneurysm contained in the retroperitoneum by repeat point-of-care ultrasound. The patient was hemodynamically stabilized and taken for emergent grafting without confirmatory imaging. The patient was later found to also have 4/4 blood cultures positive with methicillin-sensitive Staphylococcus aureus associated with an aortic valvular vegetation and a mycotic aneurysm which contributed to the abdominal aortic aneurysm rupture. This case supports the use of comprehensive point-of-care ultrasound imaging to more rapidly and more definitively differentiate types of shock and etiologies of a shock state which can lead to more timely changes in management and improvement in outcomes.