When a Brazilian man went to the doctor with a complaint of back pain, his doctors surprised him: they discovered that the man had three kidneys, not two.
To understand the cause of the 38-year-old man’s severe pain, doctors at the hospital in São Paulo, Brazil, conducted a CT scan to assess the area, according to the case report published on Wednesday (May 6th).
The scan showed that the man had a herniated or “slipped” disc, a relatively common condition in which part of the cushion-like disc between the vertebrae was dislodged.
However, it was not only the herniated disc that caught the doctors’ attention. They noticed that the man had an unusual anatomical feature. Instead of the usual two kidneys seen in a typical person, the report had three. He had a normal looking kidney on his left side and two fused kidneys located near the pelvis.
The man had no symptoms of kidney problems and organs seemed to be working normally.
Usually each kidney is connected to the bladder by a single channel called the ureter. In the man’s case, one of the pelvic kidneys was connected directly to the bladder via a ureter. However, the ureter of the other pelvic kidney had joined the ureter of the normal left-sided kidney before entering the bladder.
According to a 2013 report of a similar case published in the Internet Radiology Journal, it is rare to have three kidneys with less than 100 cases reported in the medical literature. The condition is thought to arise during embryonic development, when a structure that typically forms a single kidney splits into two.
Because the condition does not usually cause symptoms, the authors say people often don’t know they have 3 kidneys unless it is discovered accidentally through medical tests.
The man did not need medical care for his extra kidney. However, the report says that the patient took painkillers because of his back pain.