|Year : 2021 | Volume
| Issue : 1 | Page : 26-29
Association of renal scar and vesicoureteral reflux in childhood urinary tract infection in tertiary level hospitals
Rezwana Ashraf1, Ishrat Jahan2, Afroza Begum3
1 National Institute of Kidney Diseases and Urology, Dhaka, Bangladesh
2 Dhaka Medical College, Dhaka, Bangladesh
3 Department of Paediatric Nephrology, Bangabandhu Sheikh Mujib Medical University (BSMMU), Shahbag, Dhaka 1000, Bangladesh
|Date of Submission||06-Sep-2021|
|Date of Acceptance||23-Sep-2021|
|Date of Web Publication||29-Dec-2021|
Dr. Rezwana Ashraf
Department of Paediatric Nephrology, National Institute of Kidney Diseases and Urology, Dhaka
Source of Support: None, Conflict of Interest: None
Background: Urinary tract infection (UTI) is the third most common medical problem in the pediatric population, especially in infants. Vesicoureteral reflux (VUR) is common in children with UTI. Objective: The aim of this article is to assess the relationship between VUR-associated UTI and renal scar in children. Materials and Methods: A cross-sectional study was conducted among children who were admitted in the Pediatric Nephrology Department of BSMMU with UTI during the period of March 2013 to July 2014. A total of 30 UTI patients aged 1–5 years were included in the study. Children with neurogenic bladder or structural abnormality of urinary tract other than VUR were excluded from this study. History of the patients was taken and physical examination was done and recorded. Several investigations such as urinary routine and microscopic examination, culture and sensitivity with colony count, ultrasonogram of kidney, ureter, and bladder with post-void residual urine, micturating cystourethrogram, and dimercaptosuccinic acid (DMSA) renal scan were done. The collected data were analyzed by using SPSS version 12. Results: Mean age of the patients was 2.50 ± 1.18 years within the range of 1–5 years. Boys (80.0%) were predominant than girls (20.0%). Among the right kidneys 10 (33.3%) and among the left kidneys 11 (36.7%) had renal scar. There was a significant relation between increased VUR grading and increased number of renal scars on right and left kidneys (P = 0.013 and P = 0.020, respectively). There was no significant relation between increased number of UTI episodes and increased number of renal scars on right and left kidneys (P = 0.057 and P = 0.951, respectively). There was a positive correlation between VUR grade and renal scar [r = + 0.741 (P < 0.001)]. There was a positive correlation between VUR grade and renal scar [r = + 0.917 (P < 0.001)]. Conclusion: It can be concluded that severity of VUR had a significant correlation with renal scarring on DMSA scintigraphy.
Keywords: Renal scar, urinary tract infection, vesicoureteral reflux
|How to cite this article:|
Ashraf R, Jahan I, Begum A. Association of renal scar and vesicoureteral reflux in childhood urinary tract infection in tertiary level hospitals. Paediatr Nephrol J Bangladesh 2021;6:26-9
|How to cite this URL:|
Ashraf R, Jahan I, Begum A. Association of renal scar and vesicoureteral reflux in childhood urinary tract infection in tertiary level hospitals. Paediatr Nephrol J Bangladesh [serial online] 2021 [cited 2022 Jan 22];6:26-9. Available from: http://www.pnjb-online.org/text.asp?2021/6/1/26/334119
| Introduction|| |
Urinary tract infection (UTI) is the third most common renal disease in the pediatric population, especially in infants which involve renal parenchyma and renal pelvis. In most cases, the first episode of UTI occurs in the first year of life and it is believed that young growing kidneys are more vulnerable to renal parenchymal damage. Progressive renal parenchymal damage leads to long-term complications such as hypertension and end-stage renal disease (ESRD). Renal scarring is found in 6–10% of children with UTI. About 60–65% of children with febrile UTI have pyelonephritis. Prevalence of UTI in uncircumcised boy is 10 times greater than that of circumcised boy. After 1 year UTI is more common in girls than in boys. In general, 2.7–4.1% of the children with fever were found to have UTI. Unfortunately, renal scarring following pyelonephritis is more common in children than in adults. Early diagnosis, appropriate treatment along with recognition of risk factors of renal scarring, and close and continuous follow-up of patients with UTI are the most important factors in the prevention of severe complications. Vesicoureteral reflux (VUR) is the most common urological abnormality in children. It is defined as retrograde flow of urine from the bladder to ureter and renal pelvis. Children with VUR and UTI are susceptible to pyelonephritis and renal scarring. Early diagnosis of VUR and initiation of therapy might prevent potential inflammation and progression to renal parenchymal damage. There was a high incidence of acute pyelonephritis in the presence of VUR. High-grade reflux with upper UTI is a strong indicator for renal scarring. Renal scarring secondary to VUR is called reflux nephropathy. It is one of the most important causes of ESRD in children, adolescents, and young adults, which is potentially preventable. So evaluation for reflux-associated scarring is of paramount importance particularly for young children who are more vulnerable to reflux-inducing nephropathy.
| Materials and Methods|| |
The cross-sectional study was conducted in the Department of Pediatric Nephrology, Bangabandhu Sheikh Mujib Medical University, Shahbag, Dhaka from March 2013 to July 2014. Thirty UTI patients aged 1–5 years of both sexes admitted in the Pediatric Nephrology Department were enrolled. By taking written consent, enrollment was done. Initial evaluations of patients were done by taking detailed history and thorough physical examinations and were recorded in the preformed data. Several investigations such as urinary routine and microscopic examination, culture and sensitivity with colony count, ultrasonogram of kidney, ureter, and bladder with post-void residual urine, micturating cystourethrogram (MCUG), and dimercaptosuccinic acid (DMSA) renal scan were done. MCUG was done 2 weeks after antibiotic therapy or urine become sterile by urine analysis. Anterior, full bladder, and micturating films were taken after infusion of lopemiro 300 mg/mL through a catheter. VUR was determined by MCUG and graded according to the International Society of VUR. Both kidneys were evaluated independently. There were a total of 60 renal units, and each kidney was considered as one renal unit. The DMSA scan was performed 4 weeks after the last UTI with a gamma camera equipped with a low-energy, high-resolution collimator 3 h following intravenous injection of a dose of 2 mCi of 99m Technetium DMSA or 99 mTc DMSA. Small children were sedated 30 min prior to the beginning of the study. Image was performed in multiple view. Data were analyzed after collection and all the data were checked and edited. Data were entered into a computer with the help of software SPSS for Windows programmed version 12. For all statistical tests, P < 0.05 was considered as statistically significant. Categorical data were presented as frequency with percentage, and numerical data were presented as mean with standard deviation. The χ2 test and Pearson’s correlation test were done for analysis data where required.
| Results|| |
[Table 1] shows that among 30 UTI patients 24 (80.0%) had urine culture colony count >105/mL and 6 (20.0%) had pus cell >5/HPF. The mean age of the patients was 2.50 ± 1.18 years within the range of 1–5 years. These results are showed in [Table 2]. Boys (80.0%) were predominant than girls (20.0%).
|Table 1: Micro biological parameters for diagnosis of UTI in studied subjects (n = 30)|
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According to the MCUG findings, 40.0% renal units had no VUR, 6.7% had grade I, 11.7% had grade II, 18.3% had grade III, 13.3% had grade IV, and 10.0% had grade V VUR. These results are showed in [Table 3].
[Table 4] shows the grading of scar. Among the study subjects, 24 children (80.0%) had no scar in any of their kidneys. Scar was present in 6 (20.0%) children, of which grade I and II comprised the majority (>80.0%).
Ten among the right kidneys (33.3%) and 11 among the left kidneys (36.7%) had renal scar. These results are showed in [Table 5]. There was a significant relation between increased VUR grading and increased number of renal scars on right and left kidneys (P = 0.013 and P = 0.020, respectively).
There was no significant relation between increased number of UTI episodes and increased number renal scar on right and left kidney (P = 0.057 and P = 0.951 respectively). [Figure 1] shows that there was positive correlation between VUR grade and renal scar in right kidney (r = + 0.741; P < 0.001). Also it was found that there was positive correlation between VUR grade and renal scar in left kidney (r = + 0.917; P < 0.001). These results are shown in [Figure 2].
|Figure 1: Association between VUR grades and renal scar grades in the right kidney. The figure showing relationship between VUR grades and renal scar of the right kidney. There was a positive correlation between VUR grade and renal scar [r = + 0.741 (P < 0.001)]|
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|Figure 2: Association between VUR grades and renal scar grades in the left kidney: The figure showing relationship between VUR grades and renal scar grades of the left kidney. There was a positive correlation between VUR grade and renal scar [r = + 0.917 (P < 0.001)]|
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| Discussion|| |
This study analyzed 30 children with UTI to assess the relationship of VUR and renal scarring in childhood UTI. Though we know the incidence of UTI is many folds higher in females than in males after infancy; but in this study 80.0% of the children were male and only 20.0% of the children were female which shows similarity with the study of Begum et al., this may be due to more attention by the guardians regarding illness of male child in our country. Chand et al. found that females are twice as males to have VUR. It has been generally believed that young children are more prone to development of renal scarring after pyelonephritis than patients over 5 years old. In this study, 18 (60%) patients had different grades of VUR. Bhatnagar et al. from India found that 62% of children with UTI had VUR.
Among 30 patients with 60 renal units, all patients received both MCUG and DMSA renal scintigraphy. VUR was detected in 36 (60.0%) renal units. For the right kidneys, among grades I–III reflux, two (20%) had renal scar and among grades IV and V reflux, six (75%) had renal scar (P = 0.013). For the left kidneys, among grades I–III reflux, 4 (33%) had renal scar and among grades IV and V reflux 5 (83.3%) had renal scar (P = 0.020). Sorkhi et al. demonstrated that incidence of renal scarring is higher in children with high grade VUR. The positive correlation between the severity of VUR and renal scarring was confirmed in the present study, which is similar to the study of Rahman et al. Camacho et al. found that children with abnormal DMSA had a higher chance of VUR than children with normal DMSA (48.0% vs. 12.0%). Hoberman et al. also found that renal scarring was more likely to occur in children with VUR than in those without VUR (14.7% vs. 6%, P = 0.03). Goldman et al. observed that renal scan was found only in patients with VUR grade 3 and above. Therefore, higher grades of reflux were associated with higher incidence of diffuse scar.
| Conclusion|| |
From this study finding, it can be concluded that severity of VUR had significant correlation with renal scarring on DMSA scintigraphy. Higher grades of reflux were positively correlated with more severe renal scarring. It is very important to detect VUR and renal scarring, especially in the first 5 years after birth, because the kidneys are more vulnerable to reflux nephropathy.
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Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5]