An Atypical Presentation of Emphysematous Pyelonephritis Complicated by Methicillin-Resistant Staphylococcus aureus Bacteremia.

Emphysematous pyelonephritis is an acute necrotizing infection of the renal parenchyma, collecting system, and surrounding perinephric tissue, characterized by the presence of gas within these locations on imaging. It is associated with high mortality rates and is often found in diabetic patients. We present the case of a 60-year-old female, with a past history of Von Willebrand disease and hypertension, who presented to our emergency department complaining of acute-on-chronic right knee, left hip, and paraspinal lumbar back pain with an increased frequency of falling for approximately one week. She was found to have pursed-lip breathing on physical exam. Due to her vague clinical presentation, this condition was incidentally discovered on initial workup for a pulmonary embolus, found to have extensive air in the left renal collecting system on CT of the chest. Broad-spectrum antibiotics and monitoring of hemodynamics were part of the initial resuscitation with eventual percutaneous nephrostomy tube placement by interventional radiology. Post-operatively, she developed acute respiratory distress syndrome further complicated by methicillin-resistant