Speaking with VietNamNet, T.T.S., from Quang Binh Commune in Thanh Hoa Province, said that since her youth she had frequently experienced pain and discomfort in her lower back. However, multiple medical examinations and ultrasound scans failed to detect any abnormalities.

“The pain was very uncomfortable, but it only occurred once or twice a year,” she recalled.

In 2025, during a comprehensive examination at Saint Paul General Hospital in Hanoi, doctors performed a computed tomography (CT) scan and discovered that she had four kidneys.

“When I heard that I had four kidneys, I was shocked and a bit anxious. However, the doctor explained that this was a congenital malformation and had not caused any significant impact yet, so I gradually felt more at ease,” she said.

Subsequently, she was transferred to E Hospital (Hanoi) to undergo kidney stone surgery. During the course of her treatment, she was fitted with two ureteral stents. One stent was later removed at her local healthcare facility, but because the infection and stones were not completely resolved, she returned to E Hospital to continue her treatment.

Following surgery conducted last week, her health condition has stabilized, and she remains under medical observation.

The complex surgical feat

Dr. Nguyen Dinh Lien, head of the Department of Urological and Andrological Surgery at E Hospital, said the patient’s condition was exceptionally rare, with four kidneys and four corresponding ureters.

The patient had previously undergone surgery to remove kidney stones, but one renal unit had been damaged and had lost function.

Dr. Lien said the surgery was particularly challenging because of the patient’s unusual anatomy. The blood vessels supplying the kidneys differed significantly from normal anatomy, while the damaged kidney tissue was located in an abnormal position and had developed extensive adhesions to surrounding blood vessels.

“In typical duplicated-kidney cases, the non-functioning renal segment is usually located at the upper pole. In this patient, however, the accessory kidney was positioned abnormally, making dissection extremely difficult and creating a high risk of damaging the remaining healthy kidney tissue,” Dr. Lien explained.

Choosing the appropriate surgical approach presented a major challenge for the medical team.

With open surgery, the patient would face a large incision through the abdominal wall, causing prolonged pain, slow recovery, and potential risks of post-operative bowel obstruction or injury to the intestines or colon if accessed through the abdominal cavity.

The laparoscopic surgery was far from simple. The doctors had to weigh two options: transperitoneal laparoscopy and retroperitoneal laparoscopy. Transperitoneal laparoscopy offered the advantage of a broad surgical field and smoother manipulation but required invading the peritoneal cavity. 

Conversely, retroperitoneal laparoscopy helped avoid the risk of damaging intra-abdominal organs but faced severe difficulties due to the patient’s history of prior surgery, which heightened the risk of inflammatory adhesions and anatomical alterations.

Ultimately, the surgical team decided to opt for a completely laparoscopic approach via the retroperitoneal route.

During the over 3-hour operation, the team meticulously dissected and isolated the non-functioning accessory kidney, along with its supplying vascular network and the associated renal pelvis and ureter, under highly abnormal anatomical conditions.

According to Lien, a duplex kidney is a congenital malformation that occurs when a single kidney possesses two ureters instead of one. This anomaly can manifest on one or both sides of the body. The exact cause has not been definitively identified, though certain documented cases have shown a link to genetic factors.

The vast majority of individuals with duplex kidneys exhibit zero symptoms and require no medical intervention unless complications arise. However, some cases may experience complications such as urinary tract infection (UTI), frequent urination, urinary hesitation, vesicoureteral reflux (VUR), urinary tract obstruction, urinary tract stones, or renal impairment.

Phuong Thuy