Urinary Abnormalities in Asymptomatic Children of Ho Chi Minh City: A Population-Based Study

Aims: To estimate the prevalence of urinary abnormalities in asymptomatic children aged 3 to 5 and to estimate the prevalence of urological anomalies detected by renal ultrasound among children with abnormal urine findings in an urban district of Ho Chi Minh City.
Study Design: cross-sectional population-based study.
Place and Duration of Study: Twelve kindergartens in Binh Thanh district, Ho Chi Minh City, Vietnam from March to June 2012.
Methodology: There were 11,093 children aged 3 to 5 attending 25 public and 17 private kindergartens including 2,657 in wealthy wards and 8,436 in non-wealthy wards. A total sample size of 2,402 children was required. Using a probability proportional-to size method, 8 kindergartens in public area and 4 kindergartens in private area were randomly selected. Overall, 2,433 children were enrolled including 1,244 boys. The children were screened by dipstick. Those with abnormal results were confirmed by a second dipstick. Children with two positive dipsticks were retested 3 months later and underwent renal ultrasound for urological anomalies.
Results: Abnormalities were detected in 7.8% of the subjects. Prevalence of proteinuria, hematuria, nitrituria, leucocyturia, and combined nitrituria and leucocyturia were 0%, 0.3%, 0%, 5.6%, and 0.2%, respectively. Girls had more abnormal results than boys (14.1% vs 1.8%, p<0.001). After a three-month period, the number of children with persistent abnormalities was 37. The renal ultrasound detected 5 (13.5%) hydronephrosis cases. No significant difference was found when comparing public to private kindergartens and wealthy to non-wealthy region.
Conclusion: In such a region with high population density, the high prevalence of nitrituria and/or leucocyturia in girls calls for a good education for parents and caregivers in order to prevent urinary tract infection, and the low prevalence of proteinuria and hematuria suggests that the appropriate age for urinary screening in Vietnam might be over 6 years.