Sonographic measurements for kidney length in normal Saudi children: correlation with other body parameters

Normal sonographic measurements for kidney dimensions in Saudi adult population: A cross-sectional prospective study

BACKGROUND

The use of ultrasound-based measurements to determine renal size has proven valuable in the diagnosis of renal function and associated disorders. The dimensions of the abdominal organs are affected by an individual's body age, height, sex, and weight. The objective of this study was to establish the standard sonographic parameters for renal dimensions and to determine the correlation between body measurements and renal dimensions in a population of healthy adults residing in Jazan City, Saudi Arabia.

METHODS

The present study was a prospective study conducted at a single center located in Jazan City from February to August 2022. Ninety-five participants underwent abdominal ultrasonography. The process of measuring renal size through sonography entails the measurement of various dimensions of the kidney, such as renal length, width, and thickness. The demographic information of the participants, including their sex, age, height, and weight, was documented. All analyses were performed using Statistical Package for the Social Sciences v27 software.

RESULTS

The dimensions of the right kidney, specifically the length, width, and thickness, had mean value of 9.79 centimeters (cm), 5.09 cm, and 4.10 cm, respectively. The left kidney had mean dimensions of 10.1 cm, 5.09 cm, and 4.10 cm for length, width, and thickness, respectively. The left kidney was larger than the right kidney. Furthermore, male participants exhibited larger kidney measurements than their female counterparts did. A noteworthy positive correlation was observed between the thickness of the left kidney and sex, whereas no significant correlations were found with age, weight, or height.

CONCLUSION

The current study revealed that the kidney dimensions were observed to be larger in males as compared to females. The research findings indicate that there is no significant correlation between kidney dimensions and various demographic factors, such as age, height, weight, and sex. In addition, this study provides reference tables for further use.

Pediatric kidney dimensions and risk of persistent albuminuria in Mexican adolescents

In Mexico, chronic kidney disease of unknown origin is highly prevalent. Screening studies in adolescents have shown persistent microalbuminuria (pACR), adaptive podocytopathy and decreased kidney volume (KV). Here, we sought to develop normality tables of kidney dimensions by ultrasound in the Mexican state of Aguascalientes pediatric population (0 to 18y) and evaluate the relationship between the KV and pACR among the region's adolescents in a cross-sectional study. Kidney length (KL) and KV were determined by ultrasound. Our findings were compared with those in international literature of different populations where tables and graphs of normal kidney dimensions by ultrasound were reported. We compared organ dimensions in individuals above the age of 11 without albuminuria with those in patients with pACR recruited through screening studies in adolescents in Aguascalientes. This included 1068 individuals to construct percentile tables and graphs of the KL. Kidney dimensions were significantly lower when compared with all international comparisons. From a total 14,805 screen individuals, we compared 218 adolescents with pACR and 377 individuals without significant albuminuria. The Total KV adjusted to body surface (TKVBS) was significantly associated with pACR (odds ratio 1.03, 95% confidence interval 1.02-1.03). The upper quartile of TKVBS was highly associated with pACR (7.57, 4.13-13.87), hypertension (2.53, 1.66-3.86), and hyperfiltration (26 vs 11.5%). Thus, TKVBS is directly associated with pACR while greater KV, arterial hypertension, and hyperfiltration in patients with pACR suggest that the increase in volume is secondary to kidney hypertrophy. Additionally, the adaptative podocytopathy with low fibrosis seen on kidney biopsy which was performed in a subset of patients, and the smaller kidney dimensions in our population point to prenatal oligonephronia as the primary cause of the detected kidney disease.

Correlation of renal length with anthropometric and demographic data in healthy children: A prospective cross sectional study

Background

Renal size is an important parameter in the assessment of a child with renal disease. Renal size can be estimated by measuring renal length, renal volume, and cortical volume or thickness. Renal length depends on different factors, which include size, body mass index and gender. Ultrasonography is useful, non-invasive and easily available method for reliably performing the measurement of kidney length. This study was conducted to find out correlation between renal length and age and anthropometric variables in healthy children. This prospective cross sectional study was carried out with the following objectives: (a) To determine the anthropometric variable that correlated best with renal length in healthy children. (b) To develop a nomogram for renal length in healthy children.

Methods

Five hundred healthy children were included in this study. Sonographic assessment of renal length was performed using real time mechanical sector scanner with 5 MHz and 8 MHz frequency. The renal length was correlated with somatic parameters like age, weight, height, body surface area and body mass index. Regression equations were derived for each pair of dependent and independent variables.

Results

We performed the measurement of renal length in 500 healthy children. In our series, renal measuring parameters showed a good correlation with studied body parameters, height having the best correlation. Data from left and right kidneys are shown separately since there was small but statistically significant difference between them. Based on our study, using the height of the child, renal length may be calculated by using following equation: Left renal length (cm) = 0.052 × height (cm) + 1.042, Right renal length (cm) = 0.052 × height (cm) + 0.867.

Conclusions

This study provides values of renal length (mean ± 2SD) in normal Indian children and its correlation with body parameters. Renal length may be easily calculated by derived linear regression equation. Nomograms of renal length with respect to age and height have been formulated. Renal Length was found to correlate best with height of the child.

The normal reference values and estimation formulae of renal structural parameters in Chinese children based on large-sample CT data

Purpose

Our aim was to investigate the normal reference value and to establish an estimation formulae for renal structural parameters (RSPs) based on large-sample CT data of Chinese children, which can provide a data reference for the clinical assessment of kidney development and diseases in Chinese children.

Materials and Methods

A total of 438 children aged 0-17 years with normal renal CT images and basic indices were continuously collected. The bilateral RSP, including renal length (RL), renal width (RW), renal thickness (RT), renal volume (RV), renal cortical thickness (RCT), renal artery diameter (RAD) and renal CT value, were measured. Kendall's rank correlation was used to analyze the correlation between RSP and sex. Pearson's correlation was used to analyze the correlation between RSP and age, height and weight. Differences in the RSP of bilateral kidneys were analyzed via a paired samples t-test. Multiple linear regression was used to analyze the multivariate relationships between RSP and basic indices and establish the estimation formula of RSP.

Results

The RSP of normal kidneys showed a dynamic increasing trend with age, except for the CT values. The reference value ranges (95% confidence interval) of normal RSP for each age group were determined. Pearson correlation analysis demonstrated strong correlations between RSP (RL, RW, RT, RV, RCT and, RAD) and basic indices (age, height and, weight), with height exhibiting the greatest correlation coefficient, followed by age or weight. Kendall's analysis showed that none of the RSPs were correlated with sex. The RL, RW, RV and RAD of the left kidney were larger than those of the right kidney, and the RT and RCT of the right kidney exhibited opposite results. Multiple linear regression analysis demonstrated a significant linear relationship between the RSP (RL, RW, RT, RV and, RCT) and the variables of the basic indices. The estimation formulae for calculating the RSP were established.

Conclusion

This is the first Chinese study to report of the trends, normal reference values and estimation formulae of normal RSP based on large-sample CT data. These results can provide data references for assessing adequate kidney growth or disease damage in Chinese children.

Change in Growth Status and Obesity Rates among Saudi Children and Adolescents Is Partially Attributed to Discrepancies in Definitions Used: A Review of Anthropometric Measurements

Anthropometric measurements are the first step in determining the health status in children and adolescents. Clinicians require standardized protocols for proper assessment and interpretation. Therefore, this study aims to review the literature of international and Saudi national guidelines and studies previously conducted in Saudi children and adolescents to provide recommendations to establish Saudi guidelines in line with the Saudi 2030 Vision. Systematic search was conducted in several databases: Medline, PubMed, Saudi Digital Library and Google Scholar from January 1990 to January 2021. Further, 167 studies measured anthropometrics in Saudi children/adolescents; 33 of these studies contributed to the establishment/adjustment of Saudi growth charts or specific cutoffs or studied the trend of growth in representative samples or adjusted the international curves to be used in Saudis. This review warrants updating growth charts and establishing the standard cutoffs of Saudi adolescent anthropometrics to avoid over/underreporting. This review provides insights and recommendations regarding the resources that can be used to establish national guidelines in anthropometric measurements for Saudi children/adolescents. This review will help policymakers and the Ministry of Health to establish standardized protocols to be used in Saudi Arabia for anthropometric measurements that may assist in detecting malnutrition.

Kidney outcomes in early adolescence following perinatal asphyxia and hypothermia-treated hypoxic-ischaemic encephalopathy

BACKGROUND

Acute kidney injury (AKI) remains common among infants with hypothermia-treated hypoxic-ischaemic encephalopathy (HIE). Little is known about long-term kidney outcomes following hypothermia treatment. We recently reported that 21% of survivors of hypothermia-treated HIE had decreased estimated glomerular filtration rate (eGFR) based on plasma creatinine in early adolescence. Here, we assessed kidney functions more comprehensively in our population-based cohort of children born in Stockholm 2007-2009 with a history of hypothermia-treated HIE.

METHODS

At 10-12 years of age, we measured cystatin C (cyst C) to estimate GFR. Children with decreased cyst C eGFR also underwent iohexol clearance examination. We measured urine-albumin/creatinine ratio, blood pressure (BP) and kidney volume on magnetic resonance imaging. Fibroblast growth factor 23 (FGF 23) levels in plasma were assessed by enzyme-linked immunosorbent assay (ELISA). Outcomes were compared between children with and without a history of neonatal AKI.

RESULTS

Forty-seven children participated in the assessment. Two children (2/42) had decreased cyst C eGFR, for one of whom iohexol clearance confirmed mildly decreased GFR. One child (1/43) had Kidney Disease Improving Global Outcomes (KDIGO) category A2 albuminuria, and three (3/45) had elevated office BP. Subsequent ambulatory 24-h BP measurement confirmed high normal BP in one case only. No child had hypertension. Kidney volume and FGF 23 levels were normal in all children. There was no difference in any of the parameters between children with and without a history of neonatal AKI.

CONCLUSION

Renal sequelae were rare in early adolescence following hypothermia-treated HIE regardless of presence or absence of neonatal AKI. A higher resolution version of the Graphical abstract is available as Supplementary information.

Estimation of Kidney Size From Foot Length in Newborns: A Cross-Sectional Study

Background

Kidney size determination and sonographic follow-up are important in clinical diagnosis and treatment in children. Various anthropometric measurements are correlated with gestational age and birth weight and are used to identify high-risk babies in need of early interventions. Although foot length has emerged as a simple and reliable anthropometric measurement, it is not correlated with kidney size, except in the fetal period. This study was undertaken to find a correlation between foot length and kidney dimensions and estimate kidney size by finding regression equations in newborns.

Methods

We conducted a cross-sectional study and 216 newborns were enrolled at a tertiary care hospital. Foot length was measured by digital Vernier calipers and kidney dimensions were measured by ultrasonography. The Pearson correlation coefficient and simple linear regression tests were used to determine the relationship between foot length and kidney dimensions.

Results

Foot lengths and kidney dimensions were comparable in males and females as well as on the right and left sides, except for kidney length, which was found to be longer in males. Both right and left foot lengths showed highly significant (p<0.001) but small, positive correlations with corresponding side kidney length, breadth, and area, with R-values ranging from 0.2874 to 0.3668. However, the correlation between birth weight and foot length was significant, positive, and moderate (r=0.6962 and 0.6923 for right and left foot lengths, respectively). The regression equation for estimation of kidney size from foot length was obtained but the variance explained was small (e.g. R²=0.1325 for right kidney length). Out of 216 babies in our study, 10 babies had a renal anomaly.

Conclusions

We found a significant but small, positive correlation between foot length and kidney dimensions. Only 13.25% of the variance in kidney length was associated with foot length. Birth weight also had a significant and positive but small correlation with kidney dimensions. However, the correlation of birth weight with foot length was moderate, and a 57.14% variance in foot length was associated with birth weight. Multivariate regression analysis with more anthropometric parameters and gestational age may help in finding a better estimation of kidney size.

A reappraisal of pediatric abdominal surface anatomy

Surface anatomy is fundamental to clinical and surgical practices. As the surface anatomy varies with age, the purpose of this study is to provide age-standardized surface markings for the abdomen in children. A total of 155 abdominal computed tomography scans of healthy children aged 0-18 years were categorized into six groups, and the surface anatomy of the major vascular structures, solid viscera, and anatomical planes in the abdomen was analyzed. The vertebral levels of the celiac trunk, superior mesenteric artery, and hepatic portal vein formation were higher in the youngest age group, whereas the levels of the inferior mesenteric artery, formation of the inferior vena cava, and renal arteries did not differ with age. The right kidney lay between T12 and L3 and the left at T11-L3; however, both kidneys were in lower positions in younger children. The spleen was most commonly located between the 8th and 11th ribs except in toddlers. In all age groups, the hepatic portal vein formation was within the transpyloric plane and the aortic bifurcation was above the supracristal plane. In vivo reassessment of the surface anatomy enables the substantial variability of surface landmarks to be highlighted. This study demonstrates that taking account of age-related variations will increase the accuracy and therefore the clinical relevance of surface anatomy.

Association between ocular axial length and anthropometrics of Asian adults

Objective

The purpose of this study is to analyze axial length, body height, hand length, and foot length to find new factors that predict myopia and to identify gender differences as one of the factors of high myopia. A cross-sectional study was conducted as a single observation. Body height, hand length, and foot length were measured according to standard anthropometric methods. Axial length, retinal thickness, and choroidal thickness were measured using the IOL Master 700 and the Heidelberg Spectralis-OCT. To account for body height differences among participants, foot length/body height and hand length/body height were analyzed using a mixed-effects model.

Results

A total of 80 eyes (men, n = 20, 40 eyes; women, n = 20, 40 eyes) were analyzed. The mean age was 33.5 years (range 21–59 years, SD: 9.6). For choroidal thickness, there was a significant association with axial length in men (p < 0.001) and a trend toward an association in women (p = 0.072). There was also a significant association between foot length/body height and axial length in men (p = 0.015), but not in women (p = 0.58). These results suggest that factors that determine body height and foot length may be related to axial length, although they vary by gender.

Sonographic renal length and volume of normal Thai children versus their Chinese and Western counterparts

BACKGROUND

Renal size is an important indicator in the diagnosis of renal diseases and urinary tract infections in children.

PURPOSE

The purpose of this study is twofold. First, it aimed to measure the renal length and calculate the renal volume of normal Thai children using 2-dimensional ultrasonography (2D-US) and study their correlations with somatic parameters. Second, it aimed to compare the age-specific renal size of normal Thai children with the published data of their Western and Chinese counterparts.

METHODS

A total of 321 children (150 boys, 171 girls; age, 6-15 years) with a normal renal profile were prospectively recruited. All subjects underwent 2D-US by an experienced pediatric radiologist and the renal length, width, and depth were measured. Renal volume was calculated using the ellipsoid formula as recommended. The data were compared between the left and right kidneys, the sexes, and various somatic parameters. The age-specific renal lengths were compared using a nomogram derived from a Western cohort that is currently referred by many Thailand hospitals, while the renal volumes were compared with the published data of a Chinese cohort.

RESULTS

No statistically significant difference (P<0.05) was found between sexes or the right and left kidneys. The renal sizes had strong correlations with height, weight, body surface area, and age but not with body mass index. The renal length of the Thai children was moderately correlated (r=0.59) with that of the Western cohort, while the age-specific renal volume was significantly smaller (P<0.05) than that of the Chinese children.

CONCLUSION

Therefore, we concluded that the age-specific renal length and volume obtained by 2D-US would vary between children in different regions and may not be suitably used as an international standard for diagnosis, although further studies may be needed to confirm our findings.