When transplant surgeon Dinee Simpson sits in a consultation room with a patient, often they're joined by the patient's relatives.

And sometimes, particularly if the patient is black, more than a century of mistrust of the medical community also joins them.

"Patients are very frank with me in telling me they know things are unfair or experimental, and they're the hardest to convince otherwise," she said. "Those are some of the most heartbreaking cases for me."

In some families, a deeply ingrained sense of betrayal, passed down through generations, can permeate doctor visits. It's a product of medical experiments performed on slaves in the 1800s, the 40-year Tuskegee syphilis experiment that denied hundreds of black men a diagnosis or treatment, of quality medical care existing just out of geographic reach.

Simpson understands that, even as she tries to help patients leave it in the past.

Simpson, 40, is the only black, female organ transplant surgeon in Chicago. "I'm here to serve everybody," she said, "But there's a specific population that I feel has a disadvantage. … They need assistance, and I recognize that I can provide some of that assistance just by looking the way I look."

After completing medical school at New York University, Simpson moved to Boston for a medical residency through Harvard University. "I had patients cry," she said. "I had patients hug me. The reaction was incredible, simply because I looked like them. I was just a trainee."

Simpson majored in chemistry at Colgate University. By the time she knew she wanted to go to medical school, it was too late to apply for the following year. So she took a job at a tech startup, which collected data on how consumers looked for health care information online and then provided that data to drug manufacturers. "What I realized is many of the commercials didn't speak to me, didn't speak to my family members," she said. "That's when I realized that health care really needs to speak to people's culture."

Later, as a surgical resident at Boston's Brigham and Women's Hospital, she observed a living donor kidney transplant on her first day. "That sold me," she said. "Later that day, we did a kidney evaluation clinic and saw six patients. All six were African-American. That blew me away."

Black Americans suffer from kidney failure at three times the rate of whites, said the National Kidney Foundation, and make up 35 percent of all patients receiving dialysis for kidney failure, despite making up around 13 percent of the U.S. population.

Now Simpson works in a city whose population is around 33 percent black, and she finds herself engaging in sometimes transformative conversations. "Patients want a physician who will sit down and spend quality time with them," she said. "But we're a species where we first judge with our eyes, for better or worse. So when people see someone who looks like them, particularly when they're in a vulnerable situation, it helps."