Man with back pain finds out he has 3 kidneys

Having three kidneys is rare, with fewer than 100 cases reported in the medical literature.

A man in Brazil learned he had three kidneys after receiving a CT scan for low back pain. Above, the CT scan showing the man's three kidneys: A normal-appearing kidney on the man's left side, and two kidneys fused at the pelvis.
A man in Brazil learned he had three kidneys after receiving a CT scan for low-back pain. Above, the CT scan showing the man's three kidneys: A normal-appearing kidney on the man's left side, and two kidneys fused at the pelvis.
(Image credit: The New England Journal of Medicine ©2020)

When a Brazilian man went to the doctor complaining of low-back pain, his doctors got a surprise: They discovered that the man had not two, but three kidneys — a very rare condition.

To figure out the cause of the 38-year-old man's severe pain, doctors at the Hospital do Rim in São Paulo, Brazil, performed a CT scan to evaluate the area, according to a report of the case, published Wednesday (May 6) in The New England Journal of Medicine (NEJM).

Latest Videos From
OFFER: Save 45% on 'How It Works' 'All About Space' and 'All About History'!

OFFER: Save 45% on 'How It Works' 'All About Space' and 'All About History'!

For a limited time, you can take out a digital subscription to any of our best-selling science magazines for just $2.38 per month, or 45% off the standard price for the first three months.

Rachael Rettner
Contributor

Rachael is a Live Science contributor, and was a former channel editor and senior writer for Live Science between 2010 and 2022. She has a master's degree in journalism from New York University's Science, Health and Environmental Reporting Program. She also holds a B.S. in molecular biology and an M.S. in biology from the University of California, San Diego. Her work has appeared in Scienceline, The Washington Post and Scientific American.