Serum cystatin C can be used as a marker of renal function even in patients with intestinal urinary diversion

Objective:Recently,serum cystatin C(CysC)has been used as a novel marker of renal function.However,there is a lack of data on CysC levels in patients with intestinal urinary diversion(UD).Here we report CysC levels in such patients.Methods:We prospectively observed 38 patients who were diagnosed with bladder cancer and subsequently treated with radical cystectomy and UD at our institution in 2012 and 2013.Serum creatinine(sCr)and CysC were obtained optionally at the same time at least 1 month after radical cystectomy and UD.Results:The median CysC and sCr concentrations were 1.12 mg/L(range 0.75-2.47 mg/L)and 0.99 mg/dL(range 0.61-2.22 mg/dL),respectively.The median estimated concentrations of glomerular filtration rate(GFR)based on CysC(eGFRcys)and GFR based on creatinine(eGFRcreat)were 61.08 mL/min/1.73 m^2(range 22.64e99.89 mL/min/1.73 m^2)and 58.01 mL/min/1.73 m^2(range 23.48e91.82 mL/min/1.73 m2),respectively.CysC had a significant correlation with sCr(r=0.8607,p<0.0001)and eGFRcreat(r=-0.8993,p<0.0001).eGFRcys also had a significant correlation with eGFRcreat(r=0.8104,p<0.0001).Conclusion:The correlation between CysC and sCr was strong and the correlation coefficient was equivalent to that in patients without UD.The results suggest that CysC is not affected by UD and can be used as a marker of renal function similarly to sCr in patients with UD.

Comparison of incidence of acute kidney injury after robot-assisted radical prostatectomy with that after open retropubic and extraperitoneal laparoscopic radical prostatectomies in patients with prostate cancer

Background:We retrospectively evaluated the postoperative renal function in patients who had undergone radical prostatectomy to compare the incidences of postoperative acute kidney injury(AKI)among the patients who had undergone robot-assisted radical prostatectomy(RARP),retropubic radical prostatectomy(RRP),and extraperitoneal laparoscopic radical prostatectomy(exLRP).Materials and methods:Patients with prostate cancer who had undergone radical prostatectomy at our institution between 2008 and 2014 were included.Robot-assisted radical prostatectomy was performed using an intraperitoneal approach in a 25-degree Trendelenburg position,whereas other procedures were performed with the patient in the supine position.We evaluated the serum creatinine levels and estimated glomerular filtration rates immediately after surgery and on postoperative day 1.We evaluated the incidence of AKI after prostatectomy using the Acute Kidney Injury Network criteria of the Kidney Disease:Improving Global Outcomes guidelines.Results:A total of 150 consecutive patients were included,with each of the 3 groups(RARP,RRP,and exLRP)comprising 50 patients.Postoperative AKI was observed in 15(30.0%),1(2.0%),and 3(6.0%)patients in the RARP,RRP,and exLRP groups,respectively.Stage 1 AKI was observed in all the patients except one.The incidence of AKI in RARP group was significantly higher than that in the other groups(p<0.001).In the RARP group,the serum creatinine level was significantly elevated immediately after the surgery;however,it returned to baseline on postoperative day 1.Surgical procedures were the only independent factor associated with AKI incidence.Conclusions:This study suggest that compared with RRP and exLRP,RARP is associated with a higher incidence of postoperative AKI,although most patients recover rapidly.Intra-abdominal pneumoperitoneum may contribute to AKI onset.