7th August 2020

A 37-year-old lady presents to the emergency department with a 72-hour history of worsening flu-like symptoms

A 37-year-old lady presents to the emergency department with a 72-hour history of worsening flu-like symptoms, including joint pain and a headache. She also complains of sore red eyes, some ulcerations in her mouth cavity and lips, and a widespread rash. She was started on sulfasalazine prescribed for her ulcerative colitis 2 days ago. Otherwise, she does not take any regular medications or supplements. On examination, you notice that she has a high fever of 39°C and widespread atypical targets and purpuric macules over her arms, chest and back. You suspect that she may have developed Stevens-Johnson syndrome.

Which THREE of the following are important investigations for this patient? Select THREE options only.