Ms. Lan, 48, underwent a routine health check-up at Tam Anh General Hospital, TP HCM. Ultrasound and CT scans revealed her left kidney was severely dilated, resembling a large water sac, with the renal parenchyma thinned to 1-2 mm and almost no blood filtering capacity. Doctor Nguyen Tan Cuong, associate head of the Urology Department at the Center for Urology - Nephrology - Andrology, stated the cause was an 8x10 mm stone lodged in the middle third of the ureter (the tube carrying urine from the kidney to the bladder). This prolonged obstruction led to urine retention, gradual kidney dilation, and functional failure.

Doctors performed retrograde endoscopic laser lithotripsy to break up the stone in the ureter and several small stones in the kidney. A JJ stent was then placed in the patient to ensure urine flow from the kidney to the bladder, resolving the fluid retention. All stones were removed, and the ureter was temporarily drained to allow the kidney to recover.

Three months later, Ms. Lan's follow-up examination revealed severe fluid retention in the kidney. The ureteral segment where the stone had been lodged was inflamed, adhered, and narrowed, rendering it unable to drain urine even after the stones were removed. "Even with ureteral reconstruction, kidney function could not be restored," doctor Cuong stated. He further explained that retaining the kidney posed risks of infection, high blood pressure, and even more severe complications later. Ms. Lan decided to undergo surgery to remove her left kidney to prevent these complications.

The surgical team performed a laparoscopic left nephrectomy via a retroperitoneal approach. Post-surgery, Ms. Lan recovered quickly, was in good health, and was discharged after 4 days. Doctors advised the patient to attend scheduled follow-up appointments for regular kidney function assessment and to ensure the health of the remaining kidney, preventing further damage.

Doctor Cuong (left) and Doctor Pham The Anh performing laparoscopic left nephrectomy on Ms. Lan. *Photo: Tam Anh General Hospital*

According to doctor Cuong, kidney damage caused by impacted stones is a dangerous complication that occurs when a stone moves and obstructs the ureter. Late detection leads to hydronephrosis, susceptibility to infection, and gradual decline in kidney function. Therefore, timely treatment is essential upon discovering an obstructing stone to preserve kidney function. Small stones may cause little or transient pain, but kidney damage progresses silently. When detected late, the kidney may have already lost its function completely and irreversibly.

Individuals with only one kidney must protect the function of their remaining kidney. This includes drinking sufficient water, limiting salt, and avoiding self-medication with painkillers or unverified dietary supplements, which can be toxic to the kidney. They should also maintain a healthy weight, control blood pressure and blood sugar, avoid alcohol, and adhere to regular follow-up appointments and kidney function tests as advised. Should abnormal symptoms such as flank pain, swelling, painful urination, or high blood pressure appear, immediate hospital visit is necessary for timely kidney function assessment.

Ha Thanh

*The patient's name has been changed