A Comparability of Renal Length and Volume Measurements in MRI and Ultrasound in Children

Introduction: Despite the significant increase in use of magnetic resonance imaging (MRI) in children, there is still a lack of normal reference values of renal size in this method and reference values are being interpolated from the ultrasound (US) studies. The study provides comparative analysis of agreement in renal length and volume measurements between MRI and ultrasound.Materials and Methods: Ninety-three children with a mean age of 8.0 ± 6.0 years, who had undergone both renal US and MRI exams, were included in the study. Participants were divided into three subgroups; each kidney was considered separately.Group 1 included 106 kidneys without any anomalies. Group 2 comprised 48 kidneys with a dilated collecting system. Group 3 included 32 kidneys with a duplicated collecting system. Measurements were taken in three dimensions, and renal volume was calculated from the ellipsoid formula.Results: We found no significant difference between US and MRI measurements in Group 1 and Group 2. In Group 3, the difference between measurements in both imaging methods was significant. The mean difference varied from 0.05% in Group 1, 2.95% in Group 2, to 4.99% in Group 3.Conclusion: The US and MRI are comparable methods in renal size measurements. The interpolation of sonographic renal length and volume reference values to the MRI in the pediatric population is justified, as there is a strong agreement between both methods. Both methods can be used interchangeably for following up of the renal size changes in the pediatric population.

Effects of Environmental Conditions on Nephron Number: Modeling Maternal Disease and Epigenetic Regulation in Renal Development

A growing body of evidence suggests that low nephron numbers at birth can increase the risk of chronic kidney disease or hypertension later in life. Environmental stressors, such as maternal malnutrition, medication and smoking, can influence renal size at birth. Using metanephric organ cultures to model single-variable environmental conditions, models of maternal disease were evaluated for patterns of developmental impairment. While hyperthermia had limited effects on renal development, fetal iron deficiency was associated with severe impairment of renal growth and nephrogenesis with an all-proximal phenotype. Culturing kidney explants under high glucose conditions led to cellular and transcriptomic changes resembling human diabetic nephropathy. Short-term high glucose culture conditions were sufficient for long-term alterations in DNA methylation-associated epigenetic memory. Finally, the role of epigenetic modifiers in renal development was tested using a small compound library. Among the selected epigenetic inhibitors, various compounds elicited an effect on renal growth, such as HDAC (entinostat, TH39), histone demethylase (deferasirox, deferoxamine) and histone methyltransferase (cyproheptadine) inhibitors. Thus, metanephric organ cultures provide a valuable system for studying metabolic conditions and a tool for screening for epigenetic modifiers in renal development.

Computed Tomographic Assessment of Renal Volume and Its Associative Factors Among Adults

Background: Knowledge of normal renal volume is a vital parameter for clinical assessment of renal diseases because renal size is altered by various medical conditions. Variations in renal dimension in different populations and it’s relation to individual’s body parameters are evident. Different studies have recommended the need for measurement of renal dimension for specific population. This study assesses normal range of renal volume in the study population and measures their correlation with individual’s body parameters.Methods: This descriptive study was done in 261 adults. After renal length measurement on reformatted coronal images, renal width and renal thickness on axil images, renal volume was calculated by ellipsoidal formula. Descriptive statistics and parametric tests were used to evaluate the association between renal volume and different parameters.Results: This study showed a significant difference in mean renal volume between male (right and left mean renal volume 120.52 ± 26.84 cm3 and 121.00 ± 27.23 cm3 respectively) and female (right and left mean renal volume 110.11 ± 21.79 cm3 and 111.15 ± 22.34 cm3 respectively) on each side. Similarly, a significant positive correlation was found between renal volume and body height, body weight and BMI of participant for both kidneys however a significant negative correlation was observed between renal volume and age 40 years and above for both kidneys. Conclusions: This study provides morphometric data regarding normal kidneys and concludes that male renal volume is more than female and renal volume is correlated to individual’s body parameters.Keywords: Morphometric; nomogram; renal volume

Ultrasound Assessment of Kidney Sizes in Different Age Groups without Renal Disease

BACKGROUND Ultrasound imaging is a lightweight, effective, non-invasive, and radiation-free imaging tool. It helps to diagnose and treat many renal disorders, as it is known that renal size is closely related to its function. Study was carried out among individuals who do not have renal disease to investigate the normal parameters of the renal size and cortical thickness by ultrasound and determine the normal curves for these parameters that can be compared with those of patients with renal disease. METHODS This was a prospective observational study carried out in the departments of nephrology and radiology. A total of 500 balanced normotensive, male and female volunteers, between the ages of 18 and 80 years, were enrolled in the study. RESULTS Body mass index, left length, left breadth, right cortical thickness, left cortical thickness and body surface area is statistically significant with respect to gender. There is a difference between the right length, breadth, and left breadth that is not statistically significant with respect to gender. Body mass index is negatively correlated with the right breadth and left cortical thickness. The right length is positively correlated with body mass index, left length, left breadth, and right cortical thickness. Further, it is negatively correlated with the right breadth, left breadth, and left cortical thickness. Right breadth is positively and significantly correlated with body mass index, left length, left breadth, and right cortical thickness. Further, it is correlates negatively with the right length and left cortical thickness. CONCLUSIONS Our study concludes that when the height and weight of the subject were correlated with renal volume and length in both sexes, there was an important positive relationship. This association between renal volume and the height and weight of the subject was relatively stronger. KEYWORDS Renal Disease, Ultrasound, Renal Length, Cortical Thickness

A 64-slice CT angiographic study of morphologic and morphometric analysis of healthy kidney donors

The kidneys are bilaterally paired organs and serve several essential functions required to maintain a normal human physiological function. The renal size was conventionally determined on x-ray or urography by measuring the renal length distance of first lumbar vertebrae to third or fourth lumbar vertebrae. Ectopic position of the kidney can be associated with ureteric stone, vesicoureteric reflux and can predispose to iatrogenic trauma during interventional radiological and laparoscopic procedures and any surgeries. Therefore, it is important to know the variations between individuals in the level of kidney relative to the spinal column. The study aimed to analyse the morphometric and morphologic measurements of the kidney using CT angiogram in kidney donors. In this study, the length and breadth of kidney and different level of location of kidney in 100 renal donors were analysed. The study was conducted in specialised scan centres located in Chennai. Out of 100 kidney donors, 61% of them were male & 39% of them were female. The right kidney length was found to be 10.59 ±1.14 cms, and left kidney length was found to be 10.72 ± 1.22 cms. This report will be useful for transplant surgeries, as well as clinicians and radiologist who perform various techniques.

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 (<i>P</i><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 (<i>r</i>=0.59) with that of the Western cohort, while the age-specific renal volume was significantly smaller (<i>P</i><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.

Time changes of renal dimensions and variations of glomerular filtration rate in chronic kidney disease patients

Background: The aim of this longitudinal prospective study was to search if even in the absence of total or partial nephrectomy the kidney size can increase as the kidney function improves. Methods: We randomly enrolled 80 adult patients with various degrees of chronic renal failure but non-dialysis dependent neither totally or partially nephrectomized nor affected by any of the pathological conditions that can increase kidney size. The patients underwent a first examination comprehensive of a blood sample and renal ultrasonography and then were submitted to a therapeutic intervention aimed at removing all nephrotoxic agents to finally be subjected to a last similar medical examination. Results: The statistical analysis displayed a strong positive correlation between the percentage variation of the renal diameters’ average and the time changes of the GFR (r 0.731; p < 0.01) as well as the percentage variation of the GFR and the time changes variations of the right (r 0.487; p < 0.01) and left cortical kidney thickness (r 0.519; p < 0.01) and finally a strong negative correlation between the removal of nephrotoxic agents and the percentage variation of the renal diameters’ average (r - 0.293; p < 0.01) and the time changes of the GFR (r - 0.429; p < 0.01). Conclusions: In patients with chronic kidney disease, even in the absence of total or partial nephrectomy, under the stimulus of the removal of any nephrotoxic agents, there may be a limited increase in renal size according to a model that sees them vary according to the changes in GFR.

Renal disease

This chapter begins by describing the normal physiological changes that occur in pregnancy, including changes in tubular function, increased renal size, and increased blood flow. It then describes management strategies in a range of renal disorders, including haematuria, proteinuria, urinary tract infections, and both acute and chronic kidney disease. Hyperkalaemia, dialysis (and haemodialysis in pregnancy), transplantation, and medications suitable for use in the pregnant patient are all described, among others.