17-year-old Xiaolin has been a healthy kid since she was little. But recently she kept having lower back pains. At first she thought it was premenstrual syndrome. But after her period the symptoms did not ease away so she began to worry.

Everyone was shocked by the result of the ultrasound — it turns out Xiaolin has four kidneys.

A related doctor explained that the disease is called renal duplex monstrosity. The mortality rate for this is one in 1,500 people, which means most of the people would not even realize they have renal duplex monstrosity through their entire life.

Though it may show more than two kidneys when one has the disease, the extra kidneys usually attach themselves to the regular functioning ones and thus they cannot be easily removed. Consequently, functionally speaking, extra kidneys cannot be removed and used to help others in need.

Doctors eventually performed a ureteral replantation surgery and kept all of Xiaolin’s kidneys. Now Xiaolin is recovering well from the operation .