Dr. Affinati received her MD from the University of Illinois College of Medicine. She completed residency training in Internal Medicine at Advocate Lutheran General Hospital (ALGH) and was Chief Resident at ALGH. She currently serves as the Director of Clinical Education at Chicago Medical School. She served as the Internal Medicine Associate Program Director at ALGH from 1998-2018 and the Clerkship Director of Internal Medicine at ALGH from 1998-2025. She served as the Assistant Dean of Clinical Education at Chicago Medical School from 2018-2021, and the Associate Dean of Clinical Affairs from 2021-2025.

A fellow of the American College of Physicians, Dr. Affinati is the recipient of the CMS Outstanding Attending Award in Internal Medicine (2010), the Leonard Tow Humanism in Medicine Award (2014), the Dean's Special Recognition Award (2020, 2023) and the Gold Foundation Champion of Humanistic Care (2021).

Dr. Affinati is certified by the American Board of Internal Medicine.