Objective
To analyze the factors associated with the outcome of pyeloplasty in term of renal function and morphology improvement in children with unilateral ureteropelvic junction obstruction, in order to provide clinical evidence for the treatment of hydronephrosis in children.
Methods
Clinical data of 174 children who underwent unilateral dismembered pyeloplasty from January 2009 to June 2014 were retrospectively studied. Differential changes in renal function and renal morphology after pyeloplasty were assessed by serial renal scan and ultrasound. On the basis of preoperative split DRF, these patients were divided into three groups: group Ⅰ with DRF ≥40% (n = 99) , group Ⅱ with DRF 30%-40% ( n = 29) and group Ⅲwith DRF <30% (n = 46). According to their age at surgery, the children were divided into four groups, including group A aged 1-3 months (n = 52), group B aged 3 months- 3 years (n = 44), group C aged 3 - 6 years (n = 37), and group D aged more than 6 years (n = 41).
Results
In all 174 children, postoperative complication occurred in 7 cases, including urinary tract infection in 6 cases and renal atrophy in 1 case. A significant improvement of both function and morphology was confirmed in most patients (P<0.01). Patients in group Ⅰ showed stable renal function after operation(DRF 48.46%±4.80% vs. 50.78%±5.45%, P<0.01), of them who underwent pyeloplasty at 1-3 months of age showed the best obvious recovery of renal morphology. Renal function of patients in group II recovered obviously and most of them reached to the initial values (DRF 35.18%±2.95% vs. 43.91%±6.89%, P<0.01). While renal function of patients in group Ⅲ recovered significantly after surgery, most of them failed to restore the initial values(DRF 20.70%±6.90% vs. 33.78%±12.49%, P<0.01), and among them, the aged 1-3 months group possessed the best recovery. Moreover, the morphological improvement was similar to the functional improvement. The time for hydronephrosis recovered to less than Grade 2 of Society for Fetal Urology(SFU)was 6, 24 and over 24 months respectively in group I, Ⅱ and Ⅲ, and the renal morphology gradually improved with the increasing duration of follow-up.
Conclusions
The renal function and morphology of most patients improved significantly after pyeloplasty. Recovery of renal function and morphology after surgery was significantly correlated with the preoperative DRF. Early surgical intervention may improve the function and morphology recovery of the involved renal unit.
Key words:
Hydronephrosis; Ultrasonography; Renal dynamic imaging; retrospective study