A 28-year-old female patient comes to clinic for a routine p…
A 28-year-old female patient comes to clinic for a routine physical exam. While gathering her medical history, she reports a previous diagnosis of infectious mononucleosis in her late teens and mentions she has had a vitamin D deficiency because of where she lives. She is also concerned about a family history of autoimmune diseases. Considering the most recent evidence on risk factors for multiple sclerosis (MS), which of the following factors would most likely contribute to her risk of developing MS?