Abstract:

Objective: To evaluate the long-term efficacy and safety of ultrasound-guided percutaneous nephrolithotomy (PCNL) in the treatment of patients with solitary kidney stones. Methods: The clinical data of 22 patients with solitary kidney stones treated with PCNL in Peking University People’s Hospital from September 2008 to June 2014, with the follow-up data of more than 5 years were analyzed retrospectively. Perioperative indicators, postoperative stone free rate (SFR) and incidence of complications were recorded. Ultrasonography was used to evaluate the long-term stones recurrence rate. Serum creatinine and estimated glomerular filtration rate (eGFR) were used to assess the long-term renal function. Results: In this group of 22 patients, the average age was (50.3±11.8) years, with 10 cases of anatomic solitary kidneys, 12 functional solitary kidneys, and the median stone diameter was 1.65 (1.1-3.9) cm. All the patients had multiple stones, including 7 cases of staghorn stones. The median pre-operative serum creatinine was 104.5 (60.0-460.0) μmol/L, and the mean eGFR was (60.3±29.4) mL/min, showing no statistically significant difference compared with that before surgery. The mean operative time was (88.2±42.0) min, and there were 11 cases of single-channel and double-channel PCNL. The median serum creatinine on the first day after surgery was 102.0 (63.0-364.0) μmol/L, and the mean eGFR was (58.0±25.1) mL/min. The mean postoperative hospital stay was (8.7±5.2) days. In this group, 5 patients (22.7%) presented short-term complications, among which 4 patients presented postoperative infection and massive hemorrhage at the same time, which improved after conservative treatment, and 1 patient presented pleural injury and improved after closed thoracic drainage. Two patients (9.1%) developed long-term complications, and ureteral stricture occurred 3 months after operation, which improved after balloon dilatation. The median follow-up time was 6.2 (4.7-11.1) years. The median serum creatinine at the last follow-up was 104.0 (72.4-377.0) μmol/L, and the mean eGFR was (60.1±23.7) mL/min, showing no statistically significant difference compared with that before surgery. Renal function decreased in 6 patients (27.3%). Initial and final SFR were 72.7% and 100%, respectively. During the 6.2-year follow-up, 9 patients (40.9%) experienced recurrence of kidney stone. After stone recurrence, 13 lithotomy surgeries were performed, and the SFR by the latest follow-up was 63.6%. Conclusion: This study had the longest follow-up time for patients with solitary kidney stones after PCNL reported at home and abroad. Ultrasound-guided standard PCNL was safe and effective in the treatment of solitary kidney stones. Long-term follow-up results showed that the recurrence rate of kidney stones was still high, but the long-term renal function was stable after operation, and some patients showed mild renal function decline.

Key words: Solitary kidney, Kidney stones, Percutaneous nephrolithotomy, Standard, Long-term follow-up