Research Of Clinical Characteristics Of Urolithiasis Related Obstructive Nephropathy And The Impact Of Estrogen On Its Development

Part Ⅰthe Prevalence and Clinical Characteristics of Non-Functioning Kidney caused by Urolithiasis:a Single Center Study of10YearsObjectives:The existence of upper urinary tract calculus may cause complete loss of renal function which eventually results in nephrectomy. To describe the prevalence and clinical characteristics of upper urinary tract calculus cases among a series of nephrectomized patients during10years.Methods:The data of1,059nephrectomized patients between January2001and December2010in our center were reviewed. The prevalence and clinical characteristics of upper urinary tract calculi derived non-functioning kidney were analyzed.Results:Among1,059patients,177(16.7%) ones were non-functioning kidneys, which were second to renal tumor cases (801,75.6%). Upper urinary tract calculi accounted for the most cause (101,57.1%) in these non-functioning kidney cases. These patients were mainly screened by ultrasound and confirmed by CT, IVU and nuclear renography. There were44(43.6%) patients with single renal stone in ureteropelvic junction,36(35.6%) with single ureteral stone and21(20.8%) with multiple unilateral renal and ureteral stones. The average size of renal stones and ureteral stones were15.6±8.8mm (4-50mm) and13.4±4.0mm (4-21mm) in diameter respectively. Prevalence of urolithiasis derived non-functioning kidney had not changed significantly during10years even showed a slight increase. Most of the stones were more than10mm in diameter. The females or patients in low living standard were more likely to develop non-functioning kidney. Conclusions:Upper urinary tract calculus (>10mm) and loss to follow-up are the most risk factors of non-functioning kidney. Females or patients in low living standard develop non-functioning kidney more easily. Regular urinary system health examination is recommended. Routine follow-up of urolithiasis is also recommended for patients with stone history to prevent renal dysfunction. Part ⅡEstrogen Preserves Split Renal Function in Chronic Complete Unilateral Ureteral Obstruction Animal ModelObjectives:Estrogen may help to preserve renal function in chronic kidney disease. We examined whether estrogen administration or deprivation might influence the split renal function in rats subjected to chronic unilateral ureteral obstruction (UUO).Methods:Adult Female Sprague-Dawley (SD) rats were randomly divided into3groups, each containing5rats. Low-estrogen group were modeled by castration. Normal-estrogen group were left untreated and High-estrogen group were given estrogen intraperitoneal injection every other day till death. Radioimmunoassay of estrogen was done to confirm the different estrogen level. Intermittent split renal function (Glomerular Filtration Rate, GFR) examination were performed in all rats on day2, day6and day16after unilateral (left) ureteral obstruction operation by means of Single Photon Emission Computed Tomography/Computed Tomography (SPECT/CT). Pre-operation and post-operation serum creatinine were also measured. Routine hematoxylin and eosin (H.E.), immunohistochemistry (IHC) pathology examination and electron microscopy (EM) were done to compare the histological difference.Results:Low, normal and high estrogen groups were successfully established (P<0.001). In the acute stage, the GFR of obstructed kidney substantially decreased (P<0.05) in all three groups while the GFR of contralateral healthy kidney showed a greater compensatory rise in normal and high estrogen group (P<0.05). In the medium stage, the GFR of the obstructed kidney was still significantly lower than that of contralateral side (P<0.05). In the chronic stage, the GFR of obstructed kidney continued to decrease with high estrogen group significantly better preserved than low estrogen group (P<0.05). The GFR of contralateral kidney compensated more in high estrogen group (P=0.01), so was the total GFR (P<0.05). Pre-and post-operation serum creatinine showed no difference among groups respectively (P>0.05) while significant increase existed in the same group before and after operation (P<0.01). Routine H.E. examination showed significant change after operation. And low estrogen group had a significant renal fibrosis than the other two groups (P<0.05) by IHC examination of Transforming Growth Factors-β (TGF-β) and α-Smooth Muscle Actin (α-SMA). Meanwhile, EM examination was also able to show difference.Conclusions:Estrogen administration and deprivation significantly influenced the renal function. Estrogen may help to preserve the split renal function (GFR) in rats with chronic UUO.