Renal Function Improvement after Transurethral Prostate Vaporesection with Thulium YAG Laser and Resection with High- Frequency Electrical Current

Introduction. Benign prostatic hyperplasia/Benign prostatic obstruction (BPH/BPO) and chronic kidney disease (CKD) are two important public health problems in elderly men, with a huge medical and social impact on rapidly aging population globally. Clinical studies have proven obstruction of the lower urinary tract, secondary to BPO as a cause of a decreased renal fun- ction and CKD development. Conversely, the reverse process of the lower urinary tract obstruction relieve should be improving the renal function. The aim of this study is to evaluate the possibility of simultaneous improvement in renal function with transurethral prostate surgery for treatment of BPO. Methods. A randomized, study (1:1) initiated in July 2022 at the University clinic for urology in Skopje, Republic of N Macedonia, was conducted on 40 patients with BPO to compare the efficacy and safety of the two endourological transurethral surgical methods for BPO treatment: in our country the recently introduced Tm:YAG laser transurethral vaporesection of the prostate (ThuVARP) and the traditional and well-established method of transurethral resection of the prostate (TURP) by using high-frequency electric current (TURP). For evaluation two types of indicators were used, BPO related and renal function (RF) related indicators. The BPO related indicators (International Prostate Symptom Score-IPSS, maximum flow rate- Qmax, prostate volume-V, and post-void residual urine volume-PVR) were assessed preoperatively and reassessed at 6 months postoperatively. RF related indicators (serum potassium, serum creatinine, and estimated glomerular filtration rate (eGFR) evaluated with the 2021 Creatinine equation (CKD-EPI) were also assessed preoperatively and reassessed after 7-10 days, postoperatively. By comparing the pre and postoperative values within each surgical group, conclusions were drawn about the possible effect of BPO surgery on renal function improvement. Other risk factors for CKD like diabetes, hypertension, smoking, obesity, dyslipidemia and metabolic syndrome were not considered in this study. Results. Significant improvements were observed postoperatively in all BPO related indicators in both surgical groups. In the ThuVARP group, Qmax increased from 6.06 ± 2.1 to 16.59 ± 6.2 ml/s (p=0.00) and IPSS, prostate V and PVR decreased from 25 ± 1.9 to 3.56 ± 5 (p=0.00); 61.4 ± 33.4 to 26.2 ± 11.9 ml (p=00); and 142.8 ± 79.1 to 7.97 ± 11ml (p=0.00); and ml (p=0.00), respectively. In the TURP group, Qmax increased from 7.96 ± 3.5 to 18.14 ± 6.6 ml/s (p=0.00); and IPSS, prostate V and PVR decreased from 22.89 ± 4.4 to 6.68 ± 5 (p=0.00); 61.5 ± 16.2 to 21.13 ± 14.4 ml (p=0.00); and 128.9 ± 86.1 to 23.45 ± 47.2 ml (p=0.00), respectively. RF related indicators also presented significant improvements postoperatively. In the ThuVARP group, serum potassium and serum creatinine decreased from 4.44 ± 0.5 to 4.17 ± 0.4 mmol/l (p=0.019) and 86.77 ± 23.2 to 78.84 ± 19.3 (p=0.029), respectively and eGFR increased from 83.26 ± 18.3 to 88.63 ± 88.63 ± 15 ml/min/1.73m2 (p=0.049). In the TURP group, serum potassium and serum creatinine decreased from 4.32 ± 0.3 to 4.13 ± 0.5 mmol/L (p=0041); and 78.59 ± 12.3 to 73.44 ± 12 nmol/L (p=0.004), respectively and eGFR, increased from 89.05 ± 11.8 to 93.65 ± 10.70 ml/min/1.73m2 (p=0.0028). Conclusion. Our findings suggest that prostate surgery with consecutive relief of the lower urinary tract obstruction, regardless of the chosen method (ThuVARP or TURP) may improve the renal function and be potentially benefitial in CKD patients.