Reproducibility of MRI renal artery blood flow and BOLD measurements in patients with chronic kidney disease and healthy controls

2013 ◽  
Vol 40 (5) ◽  
pp. 1091-1098 ◽  
Author(s):  
Dinah S. Khatir ◽  
Michael Pedersen ◽  
Bente Jespersen ◽  
Niels H. Buus
Author(s):  
Sonja Brennan ◽  
David Watson ◽  
Michal Schneider ◽  
Donna Rudd ◽  
Yogavijayan Kandasamy

Abstract Chronic kidney disease continues to be under recognised and is associated with a significant global health burden and costs. An adverse intrauterine environment may result in a depleted nephron number and an increased risk of chronic kidney disease. Antenatal ultrasound was used to measure the foetal renal parenchymal thickness (RPT), as a novel method to estimate nephron number. Foetal renal artery blood flow was also assessed. This prospective, longitudinal study evaluated the foetal kidneys of 102 appropriately grown and 30 foetal growth-restricted foetuses between 20 and 37 weeks gestational age (GA) to provide vital knowledge on the influences foetal growth restriction has on the developing kidneys. The foetal RPT and renal artery blood flow were measured at least every 4 weeks using ultrasound. The RPT was found to be significantly thinner in growth-restricted foetuses compared to appropriately grown foetuses [likelihood ratio (LR) = 21.06, P ≤ 0.0001] and the difference increases with GA. In foetuses with the same head circumference, a growth-restricted foetus was more likely to have a thinner parenchyma than an appropriately grown foetus (LR = 8.9, P = 0.0028), supporting the principle that growth-restricted foetuses preferentially shunt blood towards the brain. No significant difference was seen in the renal arteries between appropriately grown and growth-restricted foetuses. Measurement of the RPT appears to be a more sensitive measure than current methods. It has the potential to identify infants with a possible reduced nephron endowment allowing for monitoring and interventions to be focused on individuals at a higher risk of developing future hypertension and chronic kidney disease.


2019 ◽  
Vol 35 (6) ◽  
pp. 955-964 ◽  
Author(s):  
Charlotte E Buchanan ◽  
Huda Mahmoud ◽  
Eleanor F Cox ◽  
Thomas McCulloch ◽  
Benjamin L Prestwich ◽  
...  

Abstract Background Multi-parametric magnetic resonance imaging (MRI) provides the potential for a more comprehensive non-invasive assessment of organ structure and function than individual MRI measures, but has not previously been comprehensively evaluated in chronic kidney disease (CKD). Methods We performed multi-parametric renal MRI in persons with CKD (n = 22, 61 ± 24 years) who had a renal biopsy and measured glomerular filtration rate (mGFR), and matched healthy volunteers (HV) (n = 22, 61 ± 25 years). Longitudinal relaxation time (T1), diffusion-weighted imaging, renal blood flow (phase contrast MRI), cortical perfusion (arterial spin labelling) and blood-oxygen-level-dependent relaxation rate (R2*) were evaluated. Results MRI evidenced excellent reproducibility in CKD (coefficient of variation <10%). Significant differences between CKD and HVs included cortical and corticomedullary difference (CMD) in T1, cortical and medullary apparent diffusion coefficient (ADC), renal artery blood flow and cortical perfusion. MRI measures correlated with kidney function in a combined CKD and HV analysis: estimated GFR correlated with cortical T1 (r = −0.68), T1 CMD (r = −0.62), cortical (r = 0.54) and medullary ADC (r = 0.49), renal artery flow (r = 0.78) and cortical perfusion (r = 0.81); log urine protein to creatinine ratio (UPCR) correlated with cortical T1 (r = 0.61), T1 CMD (r = 0.61), cortical (r = −0.45) and medullary ADC (r = −0.49), renal artery flow (r = −0.72) and cortical perfusion (r = −0.58). MRI measures (cortical T1 and ADC, T1 and ADC CMD, cortical perfusion) differed between low/high interstitial fibrosis groups at 30–40% fibrosis threshold. Conclusion Comprehensive multi-parametric MRI is reproducible and correlates well with available measures of renal function and pathology. Larger longitudinal studies are warranted to evaluate its potential to stratify prognosis and response to therapy in CKD.


2018 ◽  
Vol 33 (suppl_1) ◽  
pp. i589-i590
Author(s):  
Armando Coca ◽  
Ana Lucia Valencia ◽  
Cristina Ferrer ◽  
Pablo Gonzalez ◽  
Miriam Martinez ◽  
...  

Cells ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 114
Author(s):  
Chih-Yu Yang ◽  
Ting-Wen Chen ◽  
Wan-Lun Lu ◽  
Shih-Shin Liang ◽  
Hsien-Da Huang ◽  
...  

Chronic kidney disease (CKD) has long been known to cause significant digestive tract pathology. Of note, indoxyl sulfate is a gut microbe-derived uremic toxin that accumulates in CKD patients. Nevertheless, the relationship between gut microbiota, fecal indole content, and blood indoxyl sulfate level remains unknown. In our study, we established an adenine-induced CKD rat model, which recapitulates human CKD-related gut dysbiosis. Synbiotic treatment in CKD rats showed a significant reduction in both the indole-producing bacterium Clostridium and fecal indole amount. Furthermore, gut microbiota diversity was reduced in CKD rats but was restored after synbiotic treatment. Intriguingly, in our end-stage kidney disease (ESKD) patients, the abundance of indole-producing bacteria, Bacteroides, Prevotella, and Clostridium, is similar to that of healthy controls. Consistently, the fecal indole tends to be higher in the ESKD patients, but the difference did not achieve statistical significance. However, the blood level of indoxyl sulfate was significantly higher than that of healthy controls, implicating that under an equivalent indole production rate, the impaired renal excretion contributes to the accumulation of this notorious uremic toxin. On the other hand, we did identify two short-chain fatty acid-producing bacteria, Faecalibacterium and Roseburia, were reduced in ESKD patients as compared to the healthy controls. This may contribute to gut dysbiosis. We also identified that three genera Fusobacterium, Shewanella, and Erwinia, in the ESKD patients but not in the healthy controls. Building up gut symbiosis to treat CKD is a novel concept, but once proved effective, it will provide an additional treatment strategy for CKD patients.


Ultrasound ◽  
2021 ◽  
pp. 1742271X2110224
Author(s):  
Sonja Brennan ◽  
David Watson ◽  
Michal Schneider ◽  
Donna Rudd ◽  
Yogavijayan Kandasamy

Introduction The study objectives were to develop standard charts for fetal renal artery blood flow to define normal ranges and to assess the reliability of the measurements. Methods This prospective, longitudinal study reviewed 72 low-risk singleton pregnancies who had serial ultrasound examinations. Pulse wave Doppler was used to obtain the resistivity and pulsatility indices of the fetal renal arteries. Standard charts of the fetal renal arteries were created using mixed effects modelling and the intra- and interobserver reliability for the renal blood flow measurements was analysed. Results Standard charts of the normal ranges of the renal artery resistive index (RI) and pulsatility index (PI) of the fetal renal arteries were created. The 3rd, 5th, 10th, 50th, 90th, 95th and 97th centiles were calculated. The intraclass correlation coefficient was acceptable for intraobserver reliability (RI = 0.66, PI = 0.88) and poor for interobserver reliability (RI = 0.11, PI = −0.56). Conclusions These novel charts demonstrate the change of the fetal renal artery blood flow during pregnancy. These may be used in clinical practice to detect variations from these normal ranges and be useful in future studies of kidney function projection.


2018 ◽  
Vol 314 (3) ◽  
pp. F423-F429 ◽  
Author(s):  
Danielle L. Kirkman ◽  
Bryce J. Muth ◽  
Meghan G. Ramick ◽  
Raymond R. Townsend ◽  
David G. Edwards

Cardiovascular disease is the leading cause of mortality in chronic kidney disease (CKD). Mitochondrial dysfunction secondary to CKD is a potential source of oxidative stress that may impair vascular function. This study sought to determine if mitochondria-derived reactive oxygen species contribute to microvascular dysfunction in stage 3–5 CKD. Cutaneous vasodilation in response to local heating was assessed in 20 CKD patients [60 ± 13 yr; estimated glomerular filtration rate (eGFR) 46 ± 13 ml·kg−1·1.73 m−2] and 11 matched healthy participants (58 ± 2 yr; eGFR >90 ml·kg−1·1.73 m−2). Participants were instrumented with two microdialysis fibers for the delivery of 1) Ringer solution, and 2) the mitochondria- specific superoxide scavenger MitoTempo. Skin blood flow was measured via laser Doppler flowmetry during standardized local heating (42°C). Cutaneous vascular conductance (CVC) was calculated as a percentage of the maximum conductance achieved with sodium nitroprusside infusion at 43°C. Urinary isofuran/F2-isoprostane ratios were assessed by gas-chromatography mass spectroscopy. Isofuran-to-F2-isoprostane ratios were increased in CKD patients (3.08 ± 0.32 vs. 1.69 ± 0.12 arbitrary units; P < 0.01) indicative of mitochondria-derived oxidative stress. Cutaneous vasodilation was impaired in CKD compared with healthy controls (87 ± 1 vs. 92 ± 1%CVCmax; P < 0.01). Infusion of MitoTempo significantly increased the plateau phase CVC in CKD patients (CKD Ringer vs. CKD MitoTempo: 87 ± 1 vs. 93 ± 1%CVCmax; P < 0.01) to similar levels observed in healthy controls ( P = 0.9). These data provide in vivo evidence that mitochondria-derived reactive oxygen species contribute to microvascular dysfunction in CKD and suggest that mitochondrial dysfunction may be a potential therapeutic target to improve CKD-related vascular dysfunction.


2021 ◽  
pp. 75-76
Author(s):  
Bharat Bhushan ◽  
Debarshi Jana

Background: Dyslipidemia is very much common in chronic kidney disease patients and is responsible for cardiovascular disease (CKD) which is most common cause of mortality in them. So, it is necessary to study the lipid prole in CKD patients to prevent morbidity and mortality. Methods: Subjects each of 50 in number are grouped into healthy controls (group-1), CKD patients without hemodialysis (group-2), CKD patients with hemodialysis (group-3). After fasting of 12 hours, lipid prole is assessed in all cases. Results: In this study, there is increase in Total cholesterol (TC), Low Density lipoprotein (LDL), very Low-Density lipoprotein (VLDL) and Triglycerides (TG) and decrease in High Density Lipoprotein (HDL) in all CKD patients compared to healthy controls (p-value for each parameter <0.001). There is increase in TC, TG and VLDL in diabetic CKD patients compare to non-diabetic CKD patients and p-value for each parameter is <0.05. It was found that TG and VLDL increase and HDL decrease in group-3 compare to group-2 is statistically signicant (p-value for each <0.05) and no signicant variation in TC and LDL in these groups. Conclusions: Present study demonstrated that there is dyslipidemia in CKD patients irrespective of mode of management, but the derangement is much more common and signicant in CKD with hemodialysis group and they are at risk of cardiovascular disease. It is better to start lipid lowering drugs which decreases disease progression and dyslipidemia.


2018 ◽  
Vol 19 (6) ◽  
pp. 626-633 ◽  
Author(s):  
Jefferson BN Barbosa ◽  
Tuíra O Maia ◽  
Priscila S Alves ◽  
Shirley D Bezerra ◽  
Elaine CSC Moura ◽  
...  

Introduction: Blood flow restriction training can be used as an alternative to conventional exercise in chronic kidney disease patients with indication of arteriovenous fistula. Objective: Evaluating the efficacy of blood flow restriction training in the diameter and distensibility change of the cephalic vein and the diameter and flow of the radial artery, muscle strength and forearm circumference in chronic kidney disease patients with arteriovenous fistula pre-creation. Methods: A blind randomized clinical trial consisting of 26 chronic kidney disease patients allocated into a blood flow restriction training group (blood flow restriction; n = 12) and a group without blood flow restriction training (control group; n = 14). Blood flow restriction was performed at 50% of systolic blood pressure and using 40% of handgrip strength as load for the isometric exercises in both groups. Results: An increase in the diameter of the cephalic vein in the 2 cm (p = 0.008) and 10 cm segments (p = 0.001) was observed in the control group. The diameter of the radial artery increased in all segments in the blood flow restriction group (2, 10 and 20 cm; p = 0.005, p = 0.021 and p = 0.018, respectively) and in the 10 and 20 cm segments (p = 0.017 and p = 0.026) in the control group. Handgrip strength only increased in the control group (p = 0.003). Conclusion: Physical training associated with blood flow restriction increased cephalic vein diameters in both groups and was effective in increasing the diameter of the radial artery; however, it did not demonstrate superiority over the exercise group protocol without blood flow restriction.


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