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Prevalence of renal scaring caused by urinary tract infections in children: a systematic review and meta-analysis.

PURPOSE. SOURCES OF INFORMATION
Urinary tract infection (UTI) is the second most common infection in children, the most important complication of which is renal scarring. The aim of present study was to evaluate the prevalence of renal scarring after UTI in children through systematic review and meta-analysis.


METHODS
The international databases of Science Direct, PubMed, Scopus, and Web of Science and the Google Scholar search engine were searched using standard keywords. The sources found were from 2010 to 2020 and the search stage was updated until 2021.02.16. Data were analyzed using STATA-14 software and the significance level was considered at P<0.05.


RESULTS
In 29 studies with a sample size of 9,986 children, the prevalence of renal scarring in children was estimated at 35% (95% CI: 29-41). Also, the prevalence of renal scarring was in girls 61% (95% CI: 40-81) and in boys 34% (95% CI: 11-57). The prevalence of unilateral renal scarring in children was 56% (95% CI: 48-65) and bilateral renal scarring was 31% (95% CI: 14-48). In addition, the prevalence of scar was 54% in children with reflux and 12% in children without vesicoureteral reflux.


CONCLUSIONS
More than one third of people under the age of 18 after UTI have renal scarring. The prevalence of this complication in girls is about 2 times higher than that in boys and in people with reflux, it is about 4 times higher than people who do not have urinary reflux. Also, about half of people under the age of 18 suffer from unilateral renal scarring and about one third of them suffer from bilateral renal scarring.