Background Currently used pediatric kidney length normative values are based on small single-center studies, do not include kidney function assessment, and focus mostly on newborns and infants. We aimed to develop ultrasound-based kidney length normative values derived from a large group of European Caucasian children with normal kidney function. Methods Out of 1,782 children aged 0–19 years, 1,758 individuals with no present or past kidney disease and normal estimated glomerular filtration rate had sonographic assessment of kidney length. The results were correlated with anthropometric parameters and estimated glomerular filtration rate. Kidney length was correlated with age, height, body surface area, and body mass index. Height-related kidney length curves and table were generated using the LMS method. Multivariate regression analysis with collinearity checks was used to evaluate kidney length predictors. Results There was no significant difference in kidney size in relation to height between boys and girls. We found significant (p < 0.001), but clinically unimportant (Cohen’s D effect size = 0.04 and 0.06) differences between prone vs. supine position (mean paired difference = 0.64 mm, 95% CI = 0.49–0.77) and left vs. right kidneys (mean paired difference = 1.03 mm, 95% CI = 0.83–1.21), respectively. For kidney length prediction, the highest coefficient correlation was observed with height (adjusted R2 = 0.87, p < 0.0001). Conclusions We present height-related LMS-percentile curves and tables of kidney length which may serve as normative values for kidney length in children from birth to 19 years of age. The most significant predictor of kidney length was statural height. Graphic Abstract

No abstract

No abstract

Assessment of the correlation between high body mass and metabolic causes of urolithiasis in patients treated over a 2-year period in the Department of Paediatrics, Paediatric Nephrology and Allergology at the Military Institute of Medicine in Warsaw. Material and methods: A total of 109 children with urolithiasis, aged 9-18 years (mean: 13 years), were enrolled in the study. The patients were divided into two groups: Group I -children with normal body mass (body mass index <85 th percentile), and Group II -children with high body mass (body mass index ≥85 th percentile). Group I consisted of 74 children (33 girls and 41 boys). Group II comprised 35 children (23 girls and 12 boys). Blood serum and urine samples were collected and tested in the laboratory to determine the causes of urolithiasis. In addition, anthropometric parameters were evaluated, including body mass index, waist circumference, waist-to-hip ratio, body mass, and body height. Also, the lipid profile was examined, and arterial blood pressure was measured in the study subjects. Results: Children with high body mass were found to have statistically significantly higher serum uric acid levels [5.4 mg/dL (5.0-6.2) vs. 4.7 mg/dL (4.1-5.4); p < 0.05] and statistically significantly higher urinary uric acid excretion (determined on the basis of the uric acid/creatinine ratio in second morning urine) compared to children with normal body mass [0.3 (0.2-0.3) vs. 0.2 (0.2-0.3); p = 0.01]. There were no statistically significant differences in the excretion of other crystalloids. In addition, children with high body mass were shown to have significantly higher values of total cholesterol [167.

No abstract