A 13-year-old girl with fevers, chills, and rigor for the last 2 weeks presents with the MRI findings shown in Figure A. She undergoes CT-guided biopsy and culture. Final cultures reveal methicillin-resistant staphylococcus aureus (MRSA). She becomes septic and is taken to the operating room for urgent surgical debridement. Which of the following is often associated with this diagnosis and requires close surveillance in the acute setting?