Purpose: We analyzed long-term results after percutaneous nephrolithotomy (PCNL) in patients with impaired renal function.
Patients and methods: Nineteen (6.3%) of 300 patients who underwent PCNL had serum creatinine values above 1.4 mg/dL before surgery and were considered to have impaired renal function. Success rate of operation, recurrence rate, and renal functional status were evaluated.
Results: Mean follow-up time was 51.1 +/- 10.1 months. Sixteen patients completed the study, but three patients were lost to follow-up. The results of the operation were as follows: stone free in 50%, clinically insignificant residual fragments in 25%, and clinically significant residual fragments in 25% of the patients. Mean serum creatinine value was 2.30 +/- 0.56 mg/dL before surgery and 2.67 +/- 1.41 mg/dL at the end of follow-up (p = 0.386). Creatinine values decreased to normal range in six patients (37.5%). Six patients (37.5%) had stable renal function (creatinine: 1.4-4 mg/dL). Creatinine values increased (>4 mg/dL) in four patients (25%) who required renal replacement therapy. Three new patients progressed to end-stage renal failure. These three had insulin-dependent type II diabetes mellitus and one also had solitary kidney and atherosclerosis. Two patients (12.5%) had recurrences, one of these had hypercalciuria, and the other had infection stone.
Conclusion: Our results indicated that most patients presenting with kidney-stone disease and renal insufficiency experience improvement or stabilization of renal function after PCNL. The patients with solitary kidney and those with conditions such as diabetes and atherosclerosis might be at greater risk for deterioration of renal function. Patients with metabolic abnormalities and infection stones might be at higher risk for recurrence.