Abstract: Objective：To explore the distribution characteristics of blood uric acid levels and the detection rate of HUA among children attending the hospital. Design： Crosssectional survey. Methods：Children who underwent blood uric acid testing at Children's Hospital Affiliated to Zhengzhou University from July 2022 to July 2023 were included. Eligible subjects were aged >28 days at the time of uric acid testing and had a clear disease diagnosis in their medical records. HUA was defined as peripheral blood uric acid levels of ≥420 μmol·L-1 for males and ≥360 μmol·L-1 for females; levels ≥540 μmol·L-1 were classified as severe HUA. Main outcome measures：Serum uric acid level and the detection rate of HUA. Results：Among 38,317 children with blood uric acid test results, 22,534 were male and 15,783 were female. The overall median blood uric acid level was 259.3 (211.1, 316.1) μmol·L-1, with a statistically significant difference between boys and girls ［262.7 (213.0, 322.3) μmol·L-1 vs. 255.0 (208.3, 308.5) μmol·L-1, Z=10.365, P<0.001］. Blood uric acid levels in boys gradually increased with age, while girls' levels increased until age 14, then gradually declined and increased again after age 17; in all age groups except around ages 8 and 10, boys had higher blood uric acid levels than girls. A total of 3,719 cases of HUA were detected (9.7%), with detection rates of 7.7% (1,730 cases) in boys and 12.6% (1,989 cases) in girls, showing a statistically significant difference (χ2=256.882, P<0.001). The detection rate of HUA in boys increased with age, peaking at 45.8% around age 17; for girls, the detection rate increased until about age 13 (25.7%) and then gradually declined. Before age 13, the HUA detection rate was lower in boys than in girls, but higher after age 14. There were 284 cases of severe HUA (0.7%), with detection rates of 1.0%(222/22,534) in boys and 0.4% (62/15,783) in girls, showing a statistically significant difference (χ2=44.269, P<0.001). The proportion of severe HUA among children with HUA was higher in boys than girls in all age groups except around ages 7 and 17. The highest detection rates of HUA and severe HUA were observed in children with endocrine system diseases (15.3% and 1.8%, respectively), with the highest detection rate in the obesity category (46.3%, 320/691). Conclusion：Pediatric HUA is clinically common, with significant age and gender differences in blood uric acid levels. It is urgent to establish reference values for blood uric acid in children of different ages and genders in China and to develop diagnostic criteria for pediatric HUA to enhance the clinical management of affected children.

Key words: Hyperuricemia, Children and adolescents, Epidemiological characteristics, Obesity