A 99-year-old Oregon woman may have died not knowing that many of her organs were not where they should've been.

Rose Marie Bentley is thought to be the oldest person with a rare condition called situs inversus with levocardia, meaning that her heart was in the right place, but her liver and other abdominal organs grew on the left side of her body – the opposite of typical human anatomy.

Medical students at Oregon Health and Science University in Portland discovered Bentley’s condition during a gross anatomy class last spring. Cameron Walker, an assistant professor of anatomy, said his students first noticed that the blood vessels in Bentley’s chest were oddly formed, but didn’t realize the extent of the variation until later in the semester.

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“When we looked at the organs of her abdominal cavity – which has the organs of the digestive tract – they were transposed entirely right to left,” Walker said. “I’d never seen this before and the students were every bit as fascinated.”

Situs inversus with levocardia occurs in about 1 of every 22,000 births and the prognosis is typically poor, according to a study published in the Singapore Medical Journal. There have been just two documented cases of patients with this condition living into their 70s, according to the research.

Walker estimates just one in 50 million people born with Bentley’s condition live long enough to become adults. While this particular organ arrangement is usually associated with serious heart problems, he said Bentley’s heart was mostly in good shape.

Bentley’s family told the university that the only chronic conditions she suffered was arthritis, and despite having three organs removed during her life, only the surgeon who took out her appendix recorded its unusual location in his notes.

Bentley, a mother of five, enjoyed working at her church and at the animal feed store that she ran with her husband James, according to her obituary. Her daughter, Louise Allee, told the university that her mother would’ve loved this attention.

“My mom would think this was so cool,” Allee said. “She would be tickled pink that she could teach something like this. She would probably get a big smile on her face, knowing that she was different, but made it through.”

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