UMA PREMAN STOOD UP, pulled aside the pallu of her sari, and showed me a long, sickle-shaped scar on her right abdomen. “32 stitches,” she said. “People say I look young, and I tell them when you lose a kidney you lose ten years.”

Preman is 45 years old, petite and constantly animated. I met her in October, in the office of the Santhi Medical Information Centre—an NGO she founded in 1997, and runs from the ground floor of her house, in a bucolic neighborhood in the temple town of Guruvayur, in central Kerala. She told me her story from behind her desk, reeling off medical facts, sharing jokes, and occasionally breaking tempo to call out to an assistant for a file she wanted me to see. On the walls around us were numerous prize certificates she had received for her social work, including one proclaiming her “Woman of the Year 2014.”

In 1998, in her capacity as a social worker, Preman took an 18-year-old who had fallen from a tree to a hospital in Coimbatore, in Tamil Nadu. Doctors there told her that the patient had suffered “brain death”: he had no electrical function in the brain, but blood was still pumping through his body because he was on life support. In such cases, multiple organs, including the heart, lungs, pancreas, kidneys and liver, can be extracted for transplants. “The neurosurgeon there told me, ‘Uma, why don’t you suggest to the family that he do cadaveric transplantation?’” Preman recalled. The family donated both the young man’s kidneys. “That was my first exposure to transplants.”