Organ Donor Had Kidney with Five Renal Arteries in Rare Medical Anomaly

Doctors in the U.K. have announced a rare medical case where an organ donor's kidney was found to have five renal arteries. The kidney, which was about to be transplanted into a young girl, is extremely unusual. While it is not uncommon for people to have two renal arteries, more than three in a single organ is far less common.

Renal arteries supply blood to the kidneys. In the womb during fetal development, multiple proto arteries known as "mesonephric arteries" perform this task. In most cases only one artery persists, which then becomes the main source of blood.

Having multiple renal arteries is common and often identified during transplant surgeries. The prevalence of multiple arteries varies, with one recent study finding an incident rate of between 17 and 35 percent. In a review paper looking at the outcome of multiple renal artery transplants, scientists found 12.8 percent of patients had kidneys with more than one artery.

In the latest case report, doctors from Manchester said they were prepping the nine-year-old girl for surgery. She was suffering from chronic kidney disease and had a single dysplastic kidney—where the organ does not develop normally in the womb.

The kidney with five arteries. The organ was not transplanted into the nine-year-old girl because of the potential risks it posed. © The New England Journal of Medicine NEJM 2019

"During preparation of the kidney for transplantation, the donor kidney was found to have five renal arteries," the team wrote in the NEJM.

Transplanting a kidney with multiple arteries is riskier in children than it is adults, as it is more "technically challenging" and leads to an "increased risk of vascular complications," the team said. Because of this, the organ was given to a 35-year-old man instead of the girl. Three years later, the man was "clinically well."

The girl eventually underwent a live donor kidney transplant and two years later she was also doing well.

There are over 120,000 people in the U.S. currently waiting for organ transplants. More than 100,000 of these are waiting for new kidneys, according to the National Kidney Foundation. Normally, the waiting time is about 3.6 years. However, this depends on several factors, including the person's health and compatibility.

It is estimated that 13 people die every day waiting for a new kidney. In 2014, live donors accounted for around a third of all transplants. According to Mayo Clinic, these operations can help shorten the time on a waiting list and the organ generally starts working immediately after the operation, compared to deceased donors.