Review Question - QID 210898

A 17-year-old girl presents to the emergency department with a painful rash on her head. She says that she started noticing a rash 2 weeks ago that has gotten worse over time. In addition, she says that she has been very thirsty over the same time period and often needs to urgently use the restroom during the day, which has been disrupting her ability to pay attention in school. Otherwise she says that she has some headaches, but attributes this to migraines that run in her family. She does not take any medications, doesn't smoke, and drinks socially with her friends. On physical exam, a disfiguring red scalp rash is observed and radiographs reveal lytic appearing skull lesions. Further examination and testing would most likely reveal which of the following findings in this patient?