Percutaneous Nephrolithotomy in Patients With Stage 2-4 Chronic Kidney Disease

Nephrolithiasis affects an estimated 5-10% of the general population, and this percentage continues to rise. It has a prevalence of 1.7% to 18% in patients with chronic kidney disease (CKD), and nephrolithiasis-related CKD contributed to 3.2% of the total patients who started maintenance dialysis therapy. The etiology of renal insufficiency in patients with nephrolithiasis is multifactorial and includes renal obstruction, recurrent urinary tract infections, frequent surgical interventions and coexisting medical disease. According to National kidney foundation, chronic kidney disease is classified into 5 stages as follows: Stage 1: Kidney damage with normal or elevated GFR \< 90 ml/min/1.7 m2 Stage 2: Kidney damage with mildly decreased GFR 60-89 ml/min/1.7 m2 Stage 3: Moderately decreased GFR 30-59 ml/min/1.7 m2 Stage 4: Severely decreased GFR 15-29 ml/min/1.7 m2 Stage 5: Kidney Failure GFR\>15 ml/min/1.7 m2 Management of nephrolithiasis in patients with CKD is often difficult. Options for preserving kidney function include watchful waiting, shockwave lithotripsy (SWL), an endourologic approach (Percutaneous nephrolithotomy or retrograde intra-renal surgery), laparoscopic surgery or conventional open surgery. Percutaneous nephrolithotomy (PCNL) is considered as the gold standard intervention for large burden and complex renal stone disease and is associated with the highest stone free rates (SFRs). However, potentially significant complications include bleeding, sepsis, pleural and visceral injury. Therefore, the optimal management plan needs to be tailored to individual patient. Serum creatinine level has been used as a crude index of renal function in studies of patients with CKD, but it is not reliable. The glomerular filtration rate (GFR) should be used instead. GFR is the most accurate way to give health providers an estimate of functioning renal mass. Estimating GFR with the use of prediction equations is cost effective. In this study, we will prospectively evaluate the effect of percutaneous nephrolithotomy on the estimated glomerular filtration rate in Patients With Stage 2-4 chronic kidney disease.