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Effects of Intrarenal Reflux on Renal Growth in Children With Grades III-V Primary Vesicoureteral Reflux
Yang Xiuzhen1, Xu Zheming2, Li Li1
1Department of Ultrasound, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China.
Insights
Intrarenal reflux (IRR) in children with high-grade vesicoureteral reflux (VUR) hinders kidney growth. Surgical intervention prevents further growth impairment, though the affected kidney doesn't catch up, unlike unaffected kidneys.
Area of Science:
- Pediatric Nephrology
- Urology
Background:
- Intrarenal reflux (IRR) is a significant factor linking vesicoureteral reflux (VUR) to renal scarring.
- Understanding IRR's impact on renal growth is crucial for managing VUR in children.
Purpose of the Study:
- To investigate the effect of IRR on renal length in children with high-grade VUR (Grades III-V).
- To compare renal growth patterns between conservative and surgical management strategies for VUR with IRR.
Main Methods:
- A study involving 104 children with Grades III-V VUR, assessed using contrast-enhanced voiding urosonography (ceVUS).
- Patients were divided into conservative antibiotic prophylaxis (CAP) and surgical groups.
- Subgroup analysis included patients with and without IRR.
Main Results:
- IRR was present in 35.96% of cases, predominantly in upper renal segments.
- In the CAP group, persistent IRR was associated with significantly reduced renal growth compared to non-IRR and control groups.
- In the surgical group, the IRR kidney showed parallel growth, while the non-IRR kidney exhibited catch-up growth.
Conclusions:
- IRR negatively impacts renal growth in children with high-grade VUR.
- Surgical intervention for VUR with IRR leads to parallel growth of the affected kidney but not catch-up growth.
- A more aggressive treatment approach, such as surgery, is recommended for children with Grades III-V VUR and IRR.
Abstract:
The phenomenon of intrarenal reflux (IRR) has been considered a crucial link between vesicoureteral reflux (VUR) and segmental scarring. We conducted a study on renal length in 104 children diagnosed with Grades III-V VUR, with or without IRR, using contrast-enhanced voiding urosonography (ceVUS). The patients were divided into two treatment groups: the conservative antibiotic prophylaxis (CAP) group and the operation group, which were further categorized into two subgroups: the IRR group and the non-IRR group. Our findings revealed an incidence rate of 35.96% (41/114) for IRR occurrence, with 43.42% (33/76) occurring in upper renal segments, 32.89% (25/76) in lower segments, and 23.68% (18/76) in middle segments. In the CAP group where the effects of IRR persisted, the renal growth observed was as follows: IRR group-0.19 ± 0.13 cm; non-IRR group-0.39 ± 0.23 cm; contralateral negative group-0.66 ± 0.35 cm; control group-0.46 ± 0 .25 cm respectively (P < .05). In the operation group, where the effects of IRR were eliminated, the renal growth for the IRR group, non-IRR group, contralateral negative group, and control group was 0.46 ± 0.22 cm, 0.54 ± 0.31 cm, 0.67 ± 0 .42 cm, and 0.36 ± 0.17 cm respectively (P < .005). In conclusion, the presence of IRR can impact renal growth in children diagnosed with Grades III-V primary VUR. Following surgical intervention, the IRR kidney does not exhibit catch-up growth; however, it demonstrates parallel growth alongside the unaffected kidney. Conversely, the non-IRR kidney experiences catch-up growth. Therefore, for children presenting with Grades III-V primary VUR combined with IRR, a more aggressive treatment approach such as surgery is recommended.
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