Due to surgeons' unwillingness to randomize patients into different treatments

It is aimed to evaluate the treatment results, rates of success and complications, and injury given to the kidney by measuring preoperative and postoperative blood urea, creatinine, Cystatin C and Netrin-1 levels and urine Cystatin C and Netrin-1 levels in patients with lower pole or renal pelvis stone(s) undergoing either one of the treatment modalities including conventional percutaneous nephrolithotripsy (PCNL), mini PCNL, ultra-mini PCNL, micro PCNL, retrograde intrarenal surgery (RIRS) and extracorporeal shock wave lithotripsy (ESWL).

In this study, the demographic and preoperative data, imaging data, operative data and postoperative follow-up data will be prospectively recorded according to the patient information forms for the patients with lower pole and/or renal pelvis stone(s) who will undergo either one of the treatment modalities including conventional PCNL, mini PCNL, ultra-mini PCNL, micro PCNL, RIRS and ESWL.

A total of 300 (three hundred) patients, aging between 18 and 70 years, with similar stone size and location are being planned to be enrolled into the study; and will be prospectively randomized into one of six groups with a 1:1 ratio. By this means, conventional PCNL will performed to 50 (fifty) patients, mini PCNL will be performed to 50 (fifty) patients, ultra-mini PCNL will be performed to 50 (fifty) patients, micro PCNL will be performed to 50 (fifty) patients, while 50 (fifty) patients will undergo RIRS and 50 (fifty) patients will undergo ESWL.

Preoperatively, blood Cystatin C and Netrin-1, and urine Neutrophil gelatinase-associated lipocalin (NGAL), Cystatin C and Netrin-1 levels will be measured. After the treatments, blood Cystatin C and Netrin-1 levels at postoperative 6th, 12th, 24th and 48th hours will be recorded. Cystatin C and Netrin-1 levels in urine will be measured at postoperative 12th and 24th hours, while urine NGAL levels will be measured at postoperative 12th and 72nd hours. Besides these, classical kidney function tests, namely blood urea and creatinine levels, will be measured preoperatively and postoperatively at 24th and 48th hours.

Parameters listed below will be also recorded and evaluated:

1. Preoperative general evaluation data: Age, height, weight, body-mass index, concomitant comorbidities, prescriptions used, history of operation(s), American Society of Anesthesiologists (ASA) score
2. Preoperative urological evaluation data: History of ESWL/PCNL/ureterorenoscopy (URS)/RIRS/open surgery, whole blood count, kidney function tests, automatic urine test, urine culture, preoperative imaging modality (KUB, US, CT), number-dimensions-localization-composition of stone(s), existence of hydronephrosis
3. Operative data: Access fluoroscopy duration, total access duration, total fluoroscopy duration, operation duration, use of double-J stent, preoperative complications
4. Number of previous ESWL seance, total duration of ESWL, number of shots during ESWL (if any)
5. Follow-up data: Urethral catheterization time, hospitalization time, need of any other treatment for being stone-free, time to full stone-free, duration to removal of double-J stent, existence of residual stone(s), formation of new stone(s), complications in late time, medical prophylaxis
6. Stone analysis

Inclusion Criteria:

• Patients planned to undergo either conventional PCNL, mini PCNL, ultra-mini PCNL, micro PCNL, RIRS or ESWL due to kidney stone(s)
• Patients between 18 and 70 years old

Exclusion Criteria:

• Patients with unregulated diabetes mellitus and diabetic nephropathy
• Patients with a blood pressure higher than 140/80 mmHg despite use of antihypertensive drug(s) regularly
• Patients with chronic renal failure who need dialysis
• Patients who had prerenal, renal or postrenal acute kidney failure during the last 6 months
• Patients who had acute pyelonephritis during the last 6 months
• Patients younger than 18 years old or older than 70 years old
• Patients who had kidney surgery during the last 3 months and who have abnormal kidney functions
• Patients with ureteral stone who are planned to undergo endoscopic stone treatment at the same time
• Patients with a history of corticosteroid use during enrollment into the study or previous 3 months
• Patients with uncontrolled thyroid disease
• Patients who have a disease with rapid cell turn-over (like leukemia, lymphoma, etc.)
• Patients in whom PCNL/RIRS/ESWL cannot be performed due to any reason and the procedure is terminated
• Patients who are converted to open surgery due to any reason
• Patients with missing data