Clinical Effect Analysis Of Retroperitoneal Inferior Pyeloplasty For Obstructive Severe Hydronephrosis In Different Age Groups

BackgroundCongenital ureteropelvic junction obstruction（UPJO）is one of the common diseases in urology,and stenosis of the ureteropelvic junction is its most common cause,and this disease often leads to the formation of hydronephrosis.The disease is insidious in its early stages,often without obvious symptoms,and is difficult to detect in time.When detected,the fluid accumulation is aggravated by prolonged obstruction,resulting in thinning of the renal parenchyma and irreversible impairment of renal function,even leaving the kidney in a non-functional state^[1].For patients with less impaired renal function,pyeloplasty is the current gold standard of treatment,but for patients with severe hydronephrosis and severely impaired renal function,especially those with a DRF of less than 10%,the preferred treatment remains controversial^[2].Campbell urology recommends nephrectomy for patients with obstructive hydronephrosis if the affected kidney contributes less than 10%to the patient’s overall renal function^[3];however,some scholars have since observed postoperative renal function recovery in patients with DRF<10%in clinical practice,so such scholars believe that such patients cannot be treated with DRF<10%or severely depressed renal function as the basis for nephrectomy alone.Therefore,such scholars believe that patients with DRF<10%or severely low renal function should not be treated by nephrectomy based on DRF<10%or severely low renal function^[4-5],but should be treated by pyeloplasty first,and then undergo nephrectomy if the renal function has not recovered significantly after surgery.At present,both views have their advantages and disadvantages,and no consensus has been reached,so it is still difficult to choose between kidney preservation or nephrectomy in patients with obstructive severe hydronephrosis in clinical practice.ObjectiveTo compare the recovery of patients with severe hydronephrosis with pelvic ureteral obstruction in different age groups after retroperitoneal inferior pyeloplasty to investigate the postoperative therapeutic effect of patients in different age groups,in order to provide a reference for the clinical treatment of such patients.MethodSixty-seven patients with unilateral pelvic ureteral junction obstruction causing severe hydronephrosis and DRF<10%on the affected side with retroperitoneal inferior pyeloplasty to relieve upper urinary tract obstruction admitted to our urology department between January 2017and January 2022 were collected and collated.The patients were divided into 3 groups according to their age at the time of surgery:24 patients in the first group were minors（5 to 17 years old）,21patients in the second group were adults（18 to 40 years old）and 22 patients in the third group were middle-aged and elderly（>40 years old）,The data included urological ultrasound,Intravenous Urography（IVU）,CT Urography（CTU）,Magnetic Resonance Urography（MRU）,and the number of patients in the hospital.The results of Intravenous Urography（IVU）,CT Urography（CTU）,Magnetic Resonance Urography（MRU）and Emission computed tomography（ECT）were compared.The DRF,parenchymal thickness and anteroposterior renal pelvicdiameter（APD）recovery were compared between the three groups before,1 month,3 months,6 months and 12months after surgery.The correlation between age and the changes of the above indexes was also analyzed by correlation analysis.ResultsThere was no statistically significant comparison between the preoperative sex and affected side ratio,BMI,preoperative APD,and DRF in the three groups.Preoperative age was（10.21±3.901）,（26.00±6.731）and（55.95±9.414）years old,respectively,with statistically significant differences（P<0.05）.Intraoperatively,the operative times of the immature,adult and middle-aged groups were（189.46±19.53）min,（178.05±13.69）min and（175.01±12.39）min,respectively,and the operative times of the immature group were significantly higher than those of the other two groups,with statistically significant differences（P<0.01）;the rest,such as intraoperative bleeding,drainage The remaining differences,such as intraoperative bleeding,drainage tube extraction time and average hospital stay,were not statistically significant（P>0.05）.After surgery,one case of urinary leakage and one case of fever with infection occurred in the immature group,and one case of bleeding（hematuria）and one case of infection occurred in the adult and middle-aged group,respectively.In the repeated measures ANOVA,it was found that the mean APD of the three groups decreased gradually before surgery,1 month after surgery,3 months after surgery,6 months after surgery and 12 months after surgery,and there was a statistical difference between the three groups at all four time points compared with the preoperative period（P<0.05）.Comparison between groups revealed no statistical difference between the three groups preoperatively and 1 month postoperatively（P>0.05）.There was a difference between the immature and middle-aged groups at 3 months postoperatively（P<0.05）,and a statistical difference between the three groups at 6months postoperatively and 12 months postoperatively（P<0.01）.In the comparison of DRF among the three groups,it was found that the mean values of DRF in the three groups gradually increased before surgery,1 month after surgery,3 months after surgery,6 months after surgery and 12 months after surgery,and there was a statistical difference（P<0.05）between the four time points of the preoperative group and the adult group,while there was no statistical difference（P>0.05）between the four time points of the middle-aged and elderly groups.Comparison between groups revealed no statistical difference between the three groups before surgery（P>0.05）.Statistically significant differences were found between groups at 1 month postoperatively,3 months postoperatively,6 months postoperatively,and 12 months postoperatively（P<0.01）.In the comparison of renal parenchymal thickness in the three groups,it was found that the mean renal parenchymal thickness gradually increased in all three groups before surgery,1month after surgery,3 months after surgery,6 months after surgery and 12 months after surgery,and there was a statistical difference（P<0.05）between the immature and adult groups at all four time points compared with the preoperative period,while there was no statistical difference（P>0.05）between the middle-aged and elderly groups at all four time points compared with the preoperative period.In the prognostic correlation study,Pearson correlation analysis was used to analyze the correlation between APD,DRF and renal parenchymal thickness and age at 12 months postoperatively,and it was found that the mean value of?APD at 12 months postoperatively had a weak negative correlation with age（r²=0.356,P<0.05）;the mean value of?DRF and?renal parenchymal thickness at 12 months postoperatively had a significant negative correlation with age（r²=0.356,P<0.05）.correlation（statistical results:r²=0.673,P<0.05;r²=0.842,P<0.05,respectively）..ConclusionIn patients with obstructive severe hydronephrosis their recovery of renal function after pyeloplasty is influenced by many factors,especially age,and the younger the patient,the more likely the recovery of renal function;for patients under 40 years of age with a DRF of renal function<10%still have a better benefit from pyeloplasty,especially in patients who are minors;for patients over 40 years of age with a DRF of renal function<10%The benefit of direct pyeloplasty is small,and direct treatment with this procedure is not recommended.