Changes In Renal Volume Research Articles

Renal Duplex Sonographic Evaluation of Type 2 Diabetic Patients

The purpose of this study was to evaluate the renal volume and intrarenal hemodynamics with duplex sonography in a group of diabetic patients with normal renal function in comparison to nondiabetic controls. The renal volume and resistive index (RI) of segmental arteries were assessed by duplex sonography in 88 diabetic patients (44 male and 44 female; median age, 58 years [range, 37-69 years]) and 73 nondiabetic control participants (48 male and 25 female; median age, 53 years [range, 27-75 years]) without renal artery stenosis. Both renal volume and RI values in the diabetic patients were significantly higher compared to the controls (mean volume ± SD: diabetic patients, 197.3 ± 47.6 mL; controls, 162.5 ± 35.2 mL; P < .0001; RI: diabetic patients, 0.70 ± 0.05; controls, 0.59 ± 0.06; P < .0001). Renal hypertrophy was present even in diabetic patients without proteinuria (renal volume: patients without proteinuria, 198.3 ± 45.9 mL; controls, 162.5 ± 35.2 mL; P < .005). Patients with higher RI values had significantly greater proteinuria (RI <0.75, 15.9 mg/g [range, 4.2-1718.9 mg/g]; RI >0.75, 37.9 mg/g [range, 11.34-2087.0 mg/g]; P < .02). Changes in renal volume and hemodynamics are detectable on sonography in diabetic patients. Those changes are also present in patients without proteinuria or signs of renal atherosclerosis and with both normal and increased glomerular filtration rates. These results indicate a potential role of duplex sonography in the early identification of morphologic and hemodynamic renal changes in type 2 diabetic patients.

Attempting to Redefine Renal Involvement by Utilizing 3D Reconstruction Models of CT Imagings in Pediatric Acute Leukemia

AbstractAbstract 4302 Background and objectiveConventionally, renal involvement in pediatric acute leukemia have been diagnosed by ultrasonography according to the definition of unilateral or bilateral nephromegaly based on the length of major or minor axis >2SD, diffuse abnormal findings, or mass legions. However, if renal involvements are determined just only by the length of major or minor axis>2SD, overdiagnosis seems to be inevitable. Moreover, it might be difficult to detect renal mass legions by ultrasonography compared with other methods. To compensate for these shortcomings, in our hospital, we utilize contrast-enhanced CT to evaluate renal mass legions and to measure renal volume by utilizing 3D reconstruction models of CT imagings instead of measuring the length of major and minor axis of the kidney. Only when markedly decrease of renal volume before and after induction chemotherapy is observed, we define the nephromegaly at diagnosis as a true renal leukemic involvement. To assess whether our 3D-CT-based criteria for leukemic invasion to kidney could be superior to the conventional criteria, we retrospectively compared renal involvements in pediatric leukemia by conventional criteria with by 3D-CT-based criteria. Materials and MethodsBetween 2006 to 2012, 32 children were diagnosed with acute leukemia in our hospital. Enhanced CT scan was performed to the all patients before induction therapy, and a follow-up CT scan was performed after induction therapy or later stage on the patients who had abnormal CT findings at diagnosis. Mass legions, length of major and minor axis, and volume changes by utilizing enhanced CT and 3D reconstruction models calculated with the software SYNAPSE VINCENT (FUJIFILM MEDICAL), were evaluated. Results21 out of 32 patients (65.6%) presented with renal involvement when conventional criteria was used (major or minor axis >2SD, or diffuse abnormal findings or mass legions). However, when applied to our 3D-CT- based criteria (mass legions or marked decrease of renal volume before and after induction therapy), only 6 patients out of 29 patients (20.7%) showed renal involvement (volume change alone 1, mass lesions without volume change 3, mass lesion with volume change 2 as shown in fig.1). The main reasons for the discrepancy between criteria for renal invasions were as follows. In the cases diagnosed with nephromegaly by satisfying major or minor axsis >2SD, only one case showed markedly decrease of renal volume before and after induction chemotherapy, and other cases did not show any renal volume changes and even in some cases, contrary to our expectation, renal volume increased as shown in fig.2. It suggested that the nephromegaly defined by only renal length include many false positive cases. Most importantly, renal mass legions could be detected only by enhanced CT, not by ultrasonography in some cases. ConclusionOur 3D-CT-based criteria for detection of leukemia invasion to kidney is much more reliable than the conventional criteria based on nephromegaly measured by major or minor axis. [Display omitted] Disclosures:No relevant conflicts of interest to declare.

Longitudinal changes in kidney parenchymal volume associated with renal artery stenting

This study assessed the longitudinal changes in renal volume after renal artery stenting (RAS) to determine if renal mass is preserved by stenting. The study cohort consisted of 38 patients with longitudinal imaging available for renal volume quantification before and after RAS. Renal volume was estimated as (kidney length) × (width) × (depth/2) based on preoperative renal imaging. For each patient, the clinical response of blood pressure (BP) and renal function to RAS was categorized according to modified American Heart Association guidelines. Changes in renal volume were assessed using paired nonparametric analyses. The cohort was a median age of 69 years (interquartile range [IQR], 60-74 years). A favorable BP response was observed in 11 of 38 patients (28.9%). At a median interval between imaging studies of 21 months (IQR, 13-32 months), ipsilateral renal volume was significantly increased from baseline (146.8 vs 133.8 cm(3);P = .02). This represents a 6.9% relative increase in ipsilateral kidney volume from baseline. A significant negative correlation between preoperative renal volume and the relative change in renal volume postoperatively (r = -0.42; P = .0055) suggests that smaller kidneys experienced the greatest gains in renal volume after stenting. It is noteworthy that the 25 patients with no change in BP or renal function-clinical failures using traditional definitions-experienced a 12% relative increase in ipsilateral renal volume after RAS. Multivariate analysis determined that stable or improved renal volume after stenting was an independent predictor of stable or improved long-term renal function (odds ratio, 0.008; 95% confidence interval, 0.000-0.206; P = .004). These data lend credence to the belief that RAS preserves renal mass in some patients. This benefit of RAS even extends to those patients who would be considered treatment failures by traditional definitions. Patients with stable or increased renal volume after RAS had more stable renal function during long-term follow-up, whereas patients with renal volume loss after stenting were prone to deterioration of renal function.

The relationship between renal volume and renal function in autosomal dominant polycystic kidney disease

In patients with autosomal dominant polycystic kidney disease (ADPKD), renal cysts grow exponentially. Since remaining renal parenchyma has a capacity to compensate for the loss of glomerular filtration, the glomerular filtration rate (GFR) may be sustained until the disease progresses. The purpose of this study was to determine if renal volumetric indices and clinical parameters are associated with renal function in Japanese patients with ADPKD. In 73 ADPKD patients (28 men, 45 women), the associations of mean systolic blood pressure, mean diastolic blood pressure, estimated GFR (eGFR), the amount of proteinuria and albuminuria, body mass index (BMI), brachial-ankle pulse wave velocity (baPWV), ankle-brachial index, and total kidney volume (TKV) were retrospectively analyzed. Multivariate linear regression analysis showed that eGFR was significantly and independently inversely correlated with patients' age and BMI. The median change in eGFR per year (ΔeGFR/y) was -2.8ml/min/1.73m(2)/year. Multiple linear regression analysis showed that ΔeGFR/y was significantly and independently inversely correlated with the change in TKV per year (ΔTKV/y). Multiple linear regression analysis showed that ΔTKV/y was significantly related to initial TKV and the change in albuminuria per year. This study demonstrated a significant relationship between the change in renal function and the change in renal volume in Japanese ADPKD patients without renal insufficiency. It is possible that the volume measurements can be used as useful markers for disease progression in Japanese ADPKD patients.

Prospective Change in Renal Volume and Function in Children with ADPKD

Autosomal dominant polycystic kidney disease (ADPKD) is a progressive hereditary disorder affecting children and young adults. Early intervention may be necessary to significantly affect the long-term consequences of this disease. The authors conducted a 5-yr randomized clinical trial to assess the effect of BP control with angiotensin-converting enzyme inhibition (ACEI) on disease progression in 85 children and young adults with ADPKD. Study groups were determined by subject BP, including hypertension (BP >or= 95th percentile), borderline hypertension (BP 75 to 95th percentile), and severe ADPKD (BP <or=75th percentile with > 10 renal cysts). The primary outcome variable was renal volume by ultrasound, with secondary outcome variables including left ventricular mass index (LVMI) and microalbuminuria. In secondary analysis, the authors compared results between hypertensive and normotensive groups. The authors were not able to demonstrate a significant effect of ACEI on renal growth in young subjects with ADPKD. Hypertensive children were at particular risk for increases in renal volume and LVMI and decreased renal function as compared with the other study groups, and borderline hypertensive children were at high risk to develop hypertension over time. However, ACEI treatment was associated with stable renal function and LVMI in this group of children. Close monitoring of cardiovascular and renal status is indicated in ADPKD children with hypertension or borderline hypertension. In contrast to effects in hypertensive ADPKD children, ACEI treatment in normotensive or borderline hypertensive ADPKD children may prevent the development of increased LVMI and deterioration in renal function.

Renal length measured by ultrasound in adult mexican population

Renal length estimation by ultrasound is an important parameter in clinical evaluation of kidney disease and healthy donors. Changes in renal volume may be a sign of kidney disease. Correct interpretation of renal length requires the knowledge of normal limits, these have not been described for Latin American population. To describe normal renal length (RL) by ultrasonography in a group of Mexican adults. Ultrasound measure of RL in 153 healthy Mexican adults stratified by age. Describe the association of RL to several anthropometric variables. A total of 77 males and 76 females were scanner. The average age for the group was 44.12 +/- 15.44 years. The mean weight, body mass index (BMI) and height were 68.87 +/- 11.69 Kg, 26.77 +/- 3.82 kg/m2 and 160 +/- 8.62 cm respectively. Dividing the population by gender, showed a height of 166 +/- 6.15 cm for males and 154.7 +/- 5.97 cm for females (p =0.000). Left renal length (LRL) in the whole group was 105.8 +/- 7.56 mm and right renal length (RRL) was 104.3 +/- 6.45 mm (p = 0.000.) The LRL for males was 107.16 +/- 6.97 mm and for females was 104.6 +/- 7.96 mm. The average RRL for males was 105.74 +/- 5.74 mm and for females 102.99 +/- 6.85 mm (p = 0.008.) We noted that RL decreased with age and the rate of decline accelerates alter 60 years of age. Both lengths correlated significantly and positively with weight, BMI and height. The RL was significantly larger in males than in females in both kidneys (p = 0.036) in this Mexican population. Renal length declines after 60 years of age and specially after 70 years.

Increases in kidney volume in autosomal dominant polycystic kidney disease can be detected within 6 months

Kidney volume growth is considered the best surrogate marker predicting the decline of renal function in autosomal dominant polycystic kidney disease. To assess the therapeutic benefit of new drugs more rapidly, changes in kidney volume need to be determined over a short time interval. Here we measured renal volume changes by manual segmentation volumetry applied to magnetic resonance imaging scans obtained with an optimized T1-weighted acquisition protocol without gadolinium-based contrast agents. One hundred young patients with autosomal dominant polycystic kidney disease and preserved renal function had a significant increase in total kidney volume by 2.71+/-4.82% in 6 months. Volume measurements were highly reproducible and accurate, as indicated by correlation coefficients of 1.000 for intra-observer and 0.996 for inter-observer agreement, with acceptable within-subject standard deviations. The change in renal volume correlated with baseline total kidney volume in all age subgroups. Total kidney volume positively correlated with male gender, hypertension, albuminuria and a history of macrohematuria but negatively with creatinine clearance. Albuminuria was associated with accelerated volume progression. Our study shows that increases in kidney volume can be reliably measured over a 6 month period in early autosomal dominant polycystic kidney disease using unenhanced magnetic resonance imaging sequences.

Approaches to Testing New Treatments in Autosomal Dominant Polycystic Kidney Disease

Autosomal dominant polycystic kidney disease (ADPKD) is an inherited systemic disease characterized by a prolonged subclinical course of gradual renal cyst expansion, resulting in massively enlarged kidneys and renal failure by the fifth to sixth decade. Renal cyst expansion results in intrarenal ischemia and activation of the renin-angiotensin-aldosterone system (RAAS) and relates to the development and maintenance of hypertension in ADPKD. Hypertension relates to disease progression in ADPKD with regard to renal volume, proteinuria, cardiovascular complications, and progression to end-stage renal disease. Novel magnetic resonance imaging methods developed in the Consortium for Radiologic Imaging for the Study of Polycystic Kidney Disease (CRISP) provide accurate estimates of change in renal volume over a short period of time in ADPKD patients with intact renal function. In CRISP an increase in renal volume of 63.4 ml/yr was found. PKD1 status, male gender, hypertension, reduced renal blood flow, and proteinuria are associated with increased renal volume and change in renal volume over time. HALT-Polycystic Kidney Disease (HALT-PKD) is designed to test whether blockade of RAAS and/or rigorous blood pressure control play a role in slowing renal progression during early (using magnetic resonance imaging methods developed in CRISP) and during late (using measures, including composite of time to doubling of serum creatinine, onset of end-stage renal disease, or death) phases in ADPKD. Findings from CRISP and the rationale for interventions in ADPKD are described, and the design of the HALT-PKD clinical trial is outlined.

Tracking kidney volume in mice with polycystic kidney disease by magnetic resonance imaging

Polycystic kidney disease is characterized by the progressive enlargement of kidneys due to expanding fluid-filled cysts with the rate of renal volume increase held to be a marker of disease progression. Magnetic resonance imaging (MRI) is used to monitor changes in renal volume in patients with polycystic kidney disease; however, it has not been effectively used in mice to monitor changes in kidney volume during drug treatment studies. We used a powerful 9.4-T horizontal bore magnetic resonance scanner to track changes in kidney volume in pcy/pcy mice, an ortholog of nephronophthisis type 3. Mice were sequentially scanned from 4 to 30 weeks of age and kidney volumes determined from high-resolution images. Kidney volume and maximal cross-sectional surface area correlated positively with kidney weight and the histologic determination of surface area. The increase in kidney volume was exponential up to 20 weeks of age, after which there was a plateau consistent with the replacement of normal parenchyma by fibrotic tissue. Our study demonstrates that MRI accurately determines the rate of kidney volume increase in mice with polycystic kidney disease and hence may be useful in assessing the effectiveness of therapeutic agents to slow disease progression.

Renal Effects of Long-Term Ciclosporin A Treatment in a Large Animal Model

Background: Most experimental studies of chronic ciclosporin A (CsA) nephrotoxicity have been performed in rodents; however, the pig possesses several advantages. The aim of this study was to investigate renal functional and structural changes during CsA treatment with 20 mg/kg/day for 6 months in a pig model. Methods: Göttingen minipigs were randomized to oral CsA treatment or as controls. At 0, 5, 10, 15, 20 and 25 weeks body weight, blood pressure, serum creatinine, and whole blood CsA levels were measured. Magnetic resonance imaging was used to estimate relative glomerular filtration rate (rGFR), renal blood flow (RBF), kidney length and volume. Renal vascular resistance (RVR) was calculated. Kidney tissue biopsies were taken and volume fraction of cortical interstitial tissue estimated by a stereology-based method. Results: CsA induced significant increases in serum creatinine, blood pressure, RVR, and a significant decrease in RBF. Furthermore, renal volume increased significantly. This finding was inversely related to the decrease in RBF and initially followed by an increase in rGFR, which then decreased. No significant histopathological kidney changes were observed. Conclusion: CsA treatment with 20 mg/kg/day for 6 months causes increased serum creatinine, blood pressure, RVR, and renal volume along with a decrease in RBF in accordance with data obtained in humans. The initial temporal changes in renal volume and function during CsA administration have similarities to the functional changes seen in early diabetes.

Renal structure in early autosomal-dominant polycystic kidney disease (ADPKD): The Consortium for Radiologic Imaging Studies of Polycystic Kidney Disease (CRISP) cohort

Autosomal-dominant polycystic kidney disease (ADPKD) is characterized by gradual renal enlargement and cyst growth prior to loss of renal function. Standard radiographic imaging has not provided the resolution and accuracy necessary to detect small changes in renal volume or to reliably measure renal cyst volumes. The Consortium for Radiologic Imaging Studies in Polycystic Kidney Disease (CRISP) is longitudinally observing ADPKD individuals using high-resolution magnetic resonance (MR) imaging to determine if change in renal and cyst volumes can be detected over a short period of time, and if they correlate with decline in renal function early in disease. Standardization studies were conducted in phantoms and four subjects at each participating clinical center. After, in the full-scale protocol, healthy ADPKD individuals 15 to 45 years old with creatinine clearance>70 mL/min underwent standardized MR renal imaging, renal iothalamate clearance, comprehensive clinical evaluation, and determination of 24-hour urinary albumin and electrolyte excretion. Stereology was used from T1-weighted images to quantify renal volume, and region-growing thresholding was used from T2-weighted images to determine cyst volume. Renal structures were evaluated in relation to demographic, clinical, and biochemical variables using means/medians, standard deviations, and Pearson correlations. Reliability coefficients for MR renal and cyst volume measurements in phantoms were 99.9% and 89.2%, respectively. In the full-scale protocol, 241 ADPKD individuals (145 women and 96 men) were enrolled. Total renal, cyst, and % cyst volume were significantly greater in each decade group. Hypertensive individuals demonstrated greater renal, cyst, and % cyst volume than normotensive subjects. Age-adjusted renal (r = -0.31, P < 0.0001), cyst (r = -0.36, P < 0.0001), and % cyst volume (r = -0.35, P < 0.0001) were inversely related to glomerular filtration rate (GFR). Age-adjusted renal volume (r = 0.42, P < 0.0001), cystic (r = 0.39, P < 0.0001, and % cyst volume (r = 0.41, P < 0.0001) were related with urinary albumin excretion. MR measures of renal and cyst volume are reliable and accurate in patients with ADPKD. ADPKD is characterized by significant cystic involvement that increases with age. Structure (renal and cyst volume) and function (GFR) are inversely related and directly related with the presence of hypertension and urinary albumin excretion in individuals with normal renal function.

Compensatory renal response after unilateral partial and whole volume high-dose irradiation of the human kidney

Renal function was prospectively analysed in 26 patients treated with radiotherapy for various types of malignancies. In patients with gastric non-Hodgkin's lymphoma stage I–II (gNHL, n = 5), the 99mTc-diethylenetriamine-penta-acetic acid ( 99mTc-DTPA) renal uptake and the relative 99mTc-dimercapto-succinyl acid ( 99mTc-DMSA) accumulation decreased gradually and concomitantly in the high-dose, whole-volume irradiated left kidney (40 Gy/5, 5 weeks), down to 25 ± 10% (mean ± 1 S.E.M.) and 31 ± 11%, respectively, after 6–9 years. The absolute 99mTc-DMSA uptake in the left kidney declined down to 33 ± 12% whereas in the low-dose, whole-volume irradiated right kidney (12–13 Gy/3 weeks) it increased up to 187 ± 11%. When considering renal volume changes with single photon emission computed tomography, the left kidney in the gNHL patients was reduced to 30 ± 13%, with,surprisingly, a contralateral enlargement up to only 119 ± 7% ( P < 0.05). The overall renal function in this group of patients, as assessed by creatinine clearance and by [ 125I]iothalamate/ 131I]hippuran clearance was reduced to 48–68%. In the Hodgkin's disease patients (HD, n = 7) given 40 Gy in 4 weeks to 30–50% of the left kidney, the 99mTc-DTPA filtration and the relative 99mTc-DMSA uptake in the left kidney was reduced to 75 ± 4% and 81 ± 3%, respectively. The absolute 99mTc-DMSA changes were 78 ± 10% and 135 ± 13%, respectively. No significant renal functional alterations were observed in patients with either ovarian carcinoma ( n = 7) or seminoma ( n = 7). These data suggest a significant, compensatory response of the non-irradiated or low-dose irradiated kidney which, however, appears to be incomplete after contralateral, whole-volume, high-dose irradiation. Such compensatory response might be overestimated when considering only relative or absolute changes in radioactivity uptake.

ULTRASONOGRAPHIC DETERMINATION OF RENAL VOLUME IN THE DOG

Ultrasonographic linear and area measurements were performed on both kidneys of 15 clinically healthy dogs. Renal volumes were calculated from linear and area data applying three prolate ellipsoid models. Ultrasonographic volumes were then compared using linear regression analysis with kidney volumes measured in vitro by water displacement. In vivo ultrasonographic volumes had a statistically significant relationship with the in vitro volume. The highest correlation was provided by the single plane area method. There was also a correlation between body weight and ultrasonographically detected renal volume, suggesting that ultrasound imaging may be a useful method for assessment of renal volume changes in dogs with renal disease.

Changes in Renal Volume During Normal Pregnancy

Twenty-four healthy pregnant women with a normal pregnancy demonstrated a significant uniform enlargement of both kidneys. The renal volumes increased by a maximum of 30% during pregnancy. However, this could not be attributed to hydronephrosis, as the patients were selected in such a way that none with pelvectasia participated in the study. All regained normal renal volume within the first week after delivery. It is well known that a glomerular hyperfiltration takes place during normal pregnancy. Possible pathogenetic mechanisms are discussed.

Changes In Renal Volume During Normal Pregnancy

Twenty-four healthy pregnant women with a normal pregnancy demonstrated a significant uniform enlargement of both kidneys. The renal volumes increased by a maximum of 30% during pregnancy. However, this could not be attributed to hydronephrosis, as the patients were selected in such a way that none with pelvectasia participated in the study. All regained normal renal volume within the first week after delivery. It is well known that a glomerular hyperfiltration takes place during normal pregnancy. Possible pathogenetic mechanisms are discussed.

A simple new formula for relating changes in renal length to changes in renal volume.

A simple new formula for relating changes in renal length to changes in renal volume is derived. It is not assumed that the kidney is any given shape, but it is assumed that a kidney does not change its shape when it enlarges. It is shown that the fractional change in renal volume equals three times the fractional change in renal length plus three times the fractional change in renal length squared. Examples of applications of the formula using figures for changes in renal length, published elsewhere in the literature, are given for renal hypertrophy in both childhood and adult life and for volume changes during excretion urography.

Response of isolated perfused dog kidneys to epinephrine

To investigate the renal vascular changes induced by epinephrine, 21 isolated dog kidneys were perfused at constant pressure. Single injections and constant infusions of epinephrine were administered. Changes in blood and urine flow and arterial and intrarenal venous pressures were measured. Changes in renal volume were estimated with a kidney-weighing device, and determinations of cation concentrations were carried out. Data do not support the view that low doses of epinephrine cause diuresis. The previously reported afferent dilation and efferent constriction after epinephrine administration were not found in this investigation. Both increased and decreased urine flows were noted at low doses of epinephrine, whereas a fall in urine flow was consistently seen at high doses. The primary vascular effect of epinephrine is presumably on the afferent arteriole, since there was no consistent diuresis, no increase in kidney weight, a decrease in blood flow, and a decrease in filtration. Electrolyte excretion was not directly influenced by epinephrine. The pressure in the ureter was changed by epinephrine.