Abstract
Aim: This study aimed to identify the differences between primary and secondary vesicoureteric reflux (VUR) and the effect of associated bladder abnormalities on kidney function.
Patients and Methods: We retrospectively reviewed the medical records of children with VUR who were followed up at King Abdulaziz University Hospital from January 2005 to December 2010. The review included results of radiological investigations and kidney function tests. We used Chi-square test for statistical analysis and paired t-test to compare group means for initial and last creatinine levels.
Results: Ninety-nine children were included in this study. Twenty (20.2%) had primary VUR, 11 had high-grade VUR, while 9 had low-grade reflux. All children with low-grade VUR had normal dimercaptosuccinic acid ( DMSA). Renal scars were present in 72% of the children with high-grade VUR. The mean creatinine levels (initial and last) for both groups were normal. Seventy-nine (79.8%) children had secondary VUR, which was due to posterior urethral valves (PUV) (46.8%), neurogenic bladder caused by meningomyelocele (25.3%), non-neurogenic neurogenic bladder (NNB) (21.5%), or neurogenic bladder associated with prune belly syndrome (6.3%). Children with NNB, meningomyelocele and PUV had high creatinine at presentation with no considerable worsening of their kidney functions during the last visit. Renal scars were present in 49.4% of the children with secondary VUR.
Conclusion: Children with primary VUR and normal bladder had good-functioning kidneys, while those with secondary VUR associated with abnormal bladder caused by NNB, spina bifida or PUV had abnormal kidney functions. DMSA scans were useful in predicting higher grades of VUR in children with primary reflux.