Native T1 Mapping in Assessing Kidney Fibrosis for Patients With Chronic Glomerulonephritis

Purpose: To assess the utility of non-contrast enhanced native T1 mapping of the renal cortex in assessing renal fibrosis for patients with chronic glomerulonephritis (CGN).Methods: A total of 119 patients with CGN and 19 healthy volunteers (HVs) were recruited for this study. Among these patients, 43 had undergone kidney biopsy measurements. Clinical information and biopsy pathological scores were collected. According to the results of the renal biopsy, the patients were classified into the high (25–50%), low (<25%) and no renal interstitial fibrosis (IF) (0%) groups. The correlations between the T1 value in the renal cortex and each of the clinical parameters were separately analyzed. The relationships between each fibrosis group and the T1 value were also evaluated and compared between groups. Binary logistic regression analysis was further used to determine the relationship between the T1 value and renal fibrosis. Receiver operating characteristic (ROC) curves were plotted to analyze the diagnostic value of the T1 value for renal fibrosis.Results: Compared with those of the HVs, the T1 values were significantly higher in patients at all stages of chronic kidney disease (CKD) (all p < 0.05). Significant T1 differences were also revealed between patients with different stages of CKD (p < 0.05). Additionally, the T1 value correlated well with CKD stage (p < 0.05), except between CKD 2 and 3. In addition, the T1 value was positively correlated with cystatin C, neutrophil gelatinase-associated lipocalin, and serum creatinine and negatively correlated with hemoglobin, kidney length, estimated glomerular filtration rate and hematocrit (all p < 0.05). Compared with those of the no IF group, the T1 values were increased in the low- and high-IF groups (both p < 0.05). Logistic regression analysis showed that an elevated T1 value was an independent risk factor for renal fibrosis. ROC analysis suggested that the optimal critical value of T1 for predicting renal fibrosis was 1,695 ms, with a specificity of 0.778 and a sensitivity of 0.625.Conclusion: Native T1 mapping demonstrated good diagnostic performance in evaluating renal function and was an effective noninvasive method for detecting renal fibrosis in CGN patients.

Kidney length normative values in children aged 0–19 years — a multicenter study

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

Sonographic Measurement of Spleen to Left Kidney Ratio among Saudi Children

Objective: Spleen length varying according to many factors such as individual height, age and weight, determination of mild splenomegaly might be extremely inaccurate. The goal of this study was to determine the spleen to left kidney ratio in different age group among school age children in Saudi Arabia. Methods: A cross sectional study was conducted on 150 healthy subjects (66 boys and 84 girls) their age ranged from 7 to 15 years. The study was conducted at the Taawon clinic in Kharj city, Saudi Arabia. The sonographic examination was performed using Siemens (Acuson X300) machine with convex probe (3.5 – 5 MHz). Spleen and left kidney lengths were measured as well as weight and height of the subjects. Results: The result of the study showed that there is no significant different between boys and girls regarding spleen and left kidney lengths (p > 0.05). The spleen to left kidney ratio was found to be about 1.1 with 1.3 as the normal upper limit in the study sample. Conclusion: Spleen to left kidney length ratio becomes a promising method to detect non palpable splenic enlargement. Mild splenomegaly is considered if the spleen to left kidney ratio is greater than 1.3 in the absence of kidney disorders.

Evaluation of Renal Oxygenation and Hemodynamics in Patients with Chronic Kidney Disease by Blood Oxygenation Level-dependent Magnetic Resonance Imaging and Intrarenal Doppler Ultrasonography

<b><i>Introduction:</i></b> The basic pathophysiologic derangement of chronic kidney disease (CKD) begins with the loss of nephrons, leading to renal hemodynamic changes, eventually causing a reduced nephron count and renal hypoxia. The purpose of this study was to observe the renal oxygenation and renal hemodynamics of patients with CKD using blood oxygenation level-dependent (BOLD) magnetic resonance imaging (MRI) and intrarenal Doppler ultrasonography (IDU). <b><i>Methods:</i></b> The study enrolled 39 patients with stage 1–4 CKD and 19 healthy volunteers (HVs). Based on their estimated glomerular filtration rate (eGFR), CKD patients were divided into 2 subgroups: a mild renal impairment (MI) group and a moderate to severe renal impairment (MSI) group. We monitored the participants’ mean cortical T2* (COT2*) and mean medullary T2* (MET2*) values on BOLD-MRI, and measured the peak systolic velocities (PSVs), end-diastolic velocities (EDVs), renal resistive index (RI), and kidney length by IDU. We also recorded clinical indicators such as age, sex, body mass index (BMI), 24-h urinary protein (24-h Upr), serum creatinine (sCr), blood urea nitrogen (BUN), and eGFR. BOLD-MRI, IDU measurements, and the clinical indicators were compared in CKD patients and HVs by the analysis of variance and Kruskal-Wallis <i>H</i> test. Spearman’s correlation was used to assess the relationship between data from BOLD-MRI and IDU and clinical indicators. <b><i>Results:</i></b> The COT2* values were significantly higher than the MET2* values in the HV, MI, and MSI groups. COT2*, MET2*, EDV, PSV, and kidney length gradually decreased in the HV, MI, and MSI groups (all <i>p &#x3c;</i> 0.05), whereas RI and 24-h Upr gradually increased (both <i>p</i> &#x3c; 0.05). Spearman correlation analysis showed that COT2* and MET2* were significantly positively correlated with eGFR, PSV, EDV, and kidney length but were significantly negatively correlated with sCr, BUN, and 24-h Upr (all <i>p</i> &#x3c; 0.05). There was no correlation observed between the COT2* and MET2* and the RI and BMI values. <b><i>Conclusions:</i></b> Renal oxygenation and blood flow velocities were found declined as the CKD stage progressed. The BOLD-MRI and IDU techniques may have clinical value by measuring intrarenal oxygenation and renal blood perfusion to judge the severity of renal damage in patients with CKD.

MO181ULTRASOUND ASSESSMENT OF KIDNEY SIZE AND ITS CORRELATION WITH BODY MASS INDEX IN HEALTHY VOLUNTEERS WITHOUT RENAL DISEASE

Background and Aims Renal length as well as renal cortical thickness has been closely related to creatinine clearance in patients with chronic kidney disease. Our primary aim was to establish a normal range of values for kidney length in our adult population with normal renal function. Method This was a prospective observational study. Ultrasonographic assessment of renal parameters in 499 healthy volunteers between 18 to 80 years of age was done. Volunteers with any known renal condition or any co-morbidity were excluded from the study population. Correlation between body mass index (BMI) and renal parameters was assessed. Results Out of 499 volunteers 327 (65%) were males and 172(35%) were females. 17.8% volunteers were less than 30 years of age, 51.5% volunteers were in the age group of 30-60 years and 30.7 % were above 60 years of age. Mean BMI in males was 25.20 ± 3.96 kg/m2 whereas mean BMI in females was 24.08 ± 3.28 kg/m2. In males the mean cortical thickness in right kidney was 13.68+/- 2.47 mm and in left kidney cortical thickness was 13.94 ± 2.6 mm. In females right kidney cortical thickness was 12.63 ± 1.91 mm and left kidney cortical thickness was 13.40 ± 2.37 mm. In the present study the right mean renal length was 9.9 ± 40cm and left renal length was 10.19 ± 0.97cm. In our study, there was positive correlation BMI with renal length. Conclusion Size of kidney has significant ethnic and geographic basis and there is a positive correlation between BMI and kidney size in our study population.

MO089HISTOMORPHOMETRIC ANALYSIS OF GLOMERULI AND CAPILLARIES DENSITY IN THE INTERSTITIUM IN PREIMPLANTATION NEEDLE BIOPSIES OF PAIRED KIDNEYS HARVESTED FROM ADULT CADAVERIC DONORS

Background and Aims Preimplantation needle biopsy of kidney allows more precise interpretation of subsequent kidney biopsies performed after transplantation and potentially also may predict kidney graft survival. It is unknown, whether it is justified to perform the biopsy of one kidney only and then to transmit obtained results also to the second kidney or biopsies of both kidneys are mandatory. The aim of the study was to assess differences regarding glomerular volume, glomerular density and capillary density in the interstitium of both kidneys harvested from the same deceased donor. Method The study involved 40 pairs of kidneys (all together 80 kidneys) in which preimplantation kidney biopsies were performed. Kidneys were harvested from 40 deceased donors (17 females and 23 males; mean age 42.3 [37.6-47.0] years old) died because of intracranial haemorrhage (17 donors) or cerebral trauma due to accident (23 donors). Histomorphometric analysis was performed using “Olympus BX51” microscope (Olympus, Tokyo, Japan) coupled with “Olympus BX50” camera and the “cellSens Standard” software (Olympus, Tokyo, Japan). Weibel-Gomez formula was adapted to calculate glomerular volume. Results No significant differences were found between mean kidneys length [115.8 (112.4-119.1) vs.115.5 (112.5-118.5) mm], glomerular volume [2.59 (2.24-2.93) vs 2.49 (2.15-2.84) μm3 x106 ], glomerular density [3.43 (3.07-3.80) vs 3.24 (2.87-3.61) n/mm2] and interstitial capillaries density [233.58 (211.26) vs 217.80 (199.45-236.47) n/mm2] of both kidneys harvested from the same deceased donor. Conclusions 1. Both kidneys harvested from the same deceased donor did not differ significantly in kidney length, glomerular volume, glomerular density and capillary density. 2. Our results justify to preimplantation biopsy of only one kidney and the results from the histomorphometric analysis may be used in the future also for assessment of the second kidney.

Preoperative clinical and renal ultrasonography variables associated with improved systolic and diastolic blood pressure reduction after renal artery stenting

IntroductionResponse to stent-assisted angioplasty (PTA) in hypertensive patients with atherosclerotic renal artery stenosis (ARAS) is unpredictable. Therefore, the present study aimed to search for preoperative clinical and renal ultrasonography variables associated with systolic (SBP) and diastolic blood pressure (DBP) reduction.Material and methodsPreoperative clinical assessment and renal ultrasonography were performed in 202 patients who underwent PTA for ARAS (2003–2018). Patients were categorized as responders if decrease of SBP of at least 20mmHg or DBP of 5mmHg was achieved. Logistic regression models, with percentage shares, were evaluated by basic decision characteristics for ultrasonographic and clinical variables.ResultsLogistic regression analysis showed that preoperative SBP ≥145mmHg (OR,20.0 [95%CI 8.67–46.2], p<0.001), (2) baseline DBP >82 mmHg (OR,3.46 [95%CI 1.61–7.42], p=0.001), (3) prior myocardial infarction (OR,3.14 [95%CI 1.09–9.0], p=0.033), and (4) Renal-Aortic-Ratio >5.1 (OR,2.67 [95%CI 1.20-6.0], p=0.016) predicted the SBP response, with respective influence shares of 69.8%; 12.1%; 10.9%; and 7.2%. The DBP response was associated with (1) baseline SBP >145mmHg (OR,3.79 [95%CI 1.87–7.70], p<0.001), (2) baseline DBP >82mmHg (OR,6.09 [95%CI 2.88–12.9], p<0.001), (3) ARAS progression (OR,0.32 [95%CI 0.09–1.07], p=0.062), (4) contralateral kidney length>106mm (OR,0.43 [95%CI 0.22–0.86], p=0.017), and (5) bilateral PTA (OR,2.39 [95%CI 1.08–5.27], p=0.03), with respective shares of 21.8%; 35.0%; 18.2%; 13.3% and 11.8%.ConclusionsCurrent study identified clinical and ultrasonographic characteristics of patients who are likely to respond to PTA for ARAS. The RAR and contralateral kidney size may enhance prediction of response likelihood.

Determination of Gestational Age by Fetal Kidney Length Measurement after the 20th Week in Healthy Women with Uncomplicated Pregnancy in Tertiary Care Centre

Introduction: Various organs are measured to estimate the gestational age of fetus. Sonographically derived parameters used to date pregnancy include Crown rump length, Biparietal diameter, Head circumference, Femoral length and Abdominal circumference. Fetal kidney length, transcerebellar diameter and placental thickness are emerging as new parameters and are claiming to be more accurate in certain situations. In Nepalese context fetal kidney length has not been studied yet so this study was done to fill this need. Methodology: Obstetric sonography was performed in 108 pregnant women with uncomplicated pregnancy to evaluate the efficacy of FKL as a measure to calculate the predicted gestational age. Gestational age ranged from 20 weeks to term. Only patient with known LMP, previous history of normal menstrual cycle and without any exclusion criteria were included in the study. Results: The study showed mean fetal kidney length at 20-24, 25-29, 30- 34 and 35-37 weeks gestation as 22.5±0.5, 26.9±0.7, 32.32±0.7 and 36.3±0.6 respectively. Overall in combined second and third trimester , fetal kidney length showed strong linear correlation with gestation age with highest significant Pearson correlation coefficient of 0.989 as compared to other parameters (BPD=0.986, HC=0.976, AC=0.971, FL=0.984). Conclusion: Fetal kidney showed strongest linear correlation with clinical gestational age and it also demonstrated positive correlation with biparietal diameter, head circumference, abdominal circumference and femur length. Therefore fetal kidney length can be used as a reliable parameter for determination of gestational age.