Impact of contrast-enhanced ultrasound in patients with renal function impairment

AIM

To investigate the role of contrast enhanced ultrasound (CEUS) in evaluating patients with renal function impairment (RFI) showing: (1) acute renal failure (ARF) of suspicious vascular origin; or (2) suspicious renal lesions.

METHODS

We retrospectively evaluated patients addressed to CEUS over an eight years period to rule-out vascular causes of ARF (first group of 50 subjects) or assess previously found suspicious renal lesions (second group of 41 subjects with acute or chronic RFI). After preliminary grey-scale and color Doppler investigation, each kidney was investigated individually with CEUS, using 1.2-2.4 mL of a sulfur hexafluoride-filled microbubble contrast agent. Image analysis was performed in consensus by two readers who reviewed digital clips of CEUS. We calculated the detection rate of vascular abnormalities in the first group and performed descriptive statistics of imaging findings for the second group.

RESULTS

In the first group, CEUS detected renal infarction or cortical ischemia in 18/50 patients (36%; 95%CI: 23.3-50.9) and 1/50 patients (2%; 95%CI: 0.1-12), respectively. The detection rate of infarction was significantly higher (P = 0.0002; McNemar test) compared to color Doppler ultrasonography (10%). No vascular causes of ARF were identified in the remaining 31/50 patients (62%). In the second group, CEUS detected 41 lesions on 39 patients, allowing differentiation between solid lesions (21/41; 51.2%) vs complex cysts (20/41; 48.8%), and properly addressing 15/39 patients to intervention when feasible based on clinical conditions (surgery and cryoablation in 13 and 2 cases, respectively). Cysts were categorized Bosniak II, IIF, III and IV in 8, 5, 4 and 3 cases, respectively. In the remaining two patients, CEUS found 1 pseudolesion and 1 subcapsular hematoma.

CONCLUSION

CEUS showed high detection rate of renal perfusion abnormalities in patients with ARF, influencing the management of patients with acute or chronic RFI and renal masses throughout their proper characterization.

Serum uric acid as an index of impaired renal function in congestive heart failure

Background

Hyperuricemia is frequently present in patients with heart failure. Many pathological conditions, such as tissue ischemia, renal function impairment, cardiac function impairment, metabolic syndrome, and inflammatory status, may impact uric acid (UA) metabolism. This study was to assess their potential relations to UA metabolism in heart failure.

Methods

We retrospectively assessed clinical characteristics, echocardiological, renal, metabolic and inflammatory variables selected on the basis of previous evidence of their involvement in cardiovascular diseases and UA metabolism in a large cohort of randomly selected adults with congestive heart failure (n = 553). By clustering of indices, those variables were explored using factor analysis.

Results

In factor analysis, serum uric acid (SUA) formed part of a principal cluster of renal functional variables which included serum creatinine (SCr) and blood urea nitrogen (BUN). Univariate correlation coefficients between variables of patients with congestive heart failure showed that the strongest correlations for SUA were with BUN (r = 0.48, P < 0.001) and SCr (r = 0.47, P < 0.001).

Conclusions

There was an inverse relationship between SUA levels and measures of renal function in patients with congestive heart failure. The strong correlation between SUA and SCr and BUN levels suggests that elevated SUA concentrations reflect an impairment of renal function in heart failure.

Involvement of systemic venous congestion in heart failure

Systemic venous congestion has gained significant importance in the interpretation of the pathophysiology of acute heart failure, especially in the development of renal function impairment during exacerbations. In this study, we review the concept, clinical characterisation and identification of venous congestion. We update current knowledge on its importance in the pathophysiology of acute heart failure and its involvement in the prognosis. We pay special attention to the relationship between abdominal congestion, the pulmonary interstitium as filtering membrane, inflammatory phenomena and renal function impairment in acute heart failure. Lastly, we review decongestion as a new therapeutic objective and the measures available for its assessment.

The predictive value of renal parenchymal information for renal function impairment in patients with ADPKD: a multicenter prospective study

OBJECTIVE

Although the guideline indicates that total kidney volume (TKV) is an important detection indicator in patients with autosomal dominant polycystic kidney disease (ADPKD), this study attempted to demonstrate that renal parenchymal information, combined with parenchymal volume and radiomics features, may have more valuable clinical guiding significance.

METHODS

A totals of 340 ADPKD patients with normal renal function were prospectively collected and followed-up for five years, with renal function tests and non-contrast computed tomography (CT) performed every six months. The relationship between renal function impairment and renal parenchymal volume (RPV) as along with radiomics features was explored using a multiple linear regression model and multiple logistic regression. Then, a combined model of RPV with radiomics features was constructed to comprehensively evaluate its predictive value.

RESULTS

Compared with TKV, decreased RPV presented a closer relationship with renal function impairment, namely, with the impairment rate (RPV: 82.3% vs. TVK: 67.1%) and eGFR (RPV: r = 0.614, p < 0.001 vs. TKV: r = -0.452, p < 0.001), and showed higher predictive power (RPV: AUC = 0.752 [95%CI 0.692-0.805], p < 0.001 vs. TKV: AUC = 0.711 [95%CI 0.649-0.768], p < 0.001). Correspondingly, the radiomics analysis that was derived from the renal parenchyma also showed a satisfactory result (AUC = 0.849 [95%Cl 0.797-0.892], p < 0.001). Importantly, the predictive power for renal function impairment was further improved in the combined model of RPV and radiomics features (AUC = 0.902 [95%Cl 0.857-0.937], p < 0.001).

CONCLUSION

Renal parenchyma information may be a sensitive biomarker of renal function impairment in ADPKD, which can provide a new approach for clinically monitoring renal function, and may greatly improve the pre-hospital prevention and treatment effects.

Tripterygium glycoside tablet attenuates renal function impairment in diabetic nephropathy mice by regulating triglyceride metabolism

Tripterygium glycoside tablet (TGT) has been used clinically to alleviate diabetic nephropathy (DN) for decades. However, the mechanism of its anti-DN has not been fully clarified. The aim of this study was to elucidate molecular mechanism of TGT in repairing renal function injury. The results of biochemical parameters and renal histopathology implied that TGT intervention could attenuate creatinine, albumin excretion rate and histological injury of kidney in DN mouse model. Moreover, UHPLC-QTOF-MS/MS-based untargeted metabolomic analysis indicated that 11 metabolites in kidney of mice with DN were restored after TGT treatment, and the most prominent metabolic alteration was triglyceride (TG) metabolism. Mechanistically, TGT effectively improved the function of impaired kidney by promoting TG catabolism via modulation of adipose triglyceride lipase in DN mice. Our findings identified the link between circulating metabolites and DN, suggesting that it might be a possibility to intervene in DN by targeting metabolism.

Renal dysfunction in patients with nonalcoholic fatty liver disease and risk factors

AIM

To assess the renal function in patients with nonalcoholic fatty liver disease (NAFLD) and to identify the risk factors for renal dysfunction.

METHODS

A total of 856 volunteers who underwent health examination were initially enrolled in this study to identify those with NAFLD. The biochemical indexes of patients with NAFLD and healthy volunteers were statistically analyzed, and the renal function with estimated glomerular filtration rate was calculated. In addition, the risk factors for renal damage were identified.

RESULTS

A total of 253 patients with NAFLD were identified, and the remaining 603 cases were used as a control group. There was no significant difference in serum BUN between the two groups (t = 1.678, P = 0.062), while other biochemical indexes differed significantly (P < 0.05). The prevalence of renal function impairment was higher in individuals with NAFLD compared to those without (28.8% vs 17.5%, P < 0.0001). Logistic regression analysis showed that NAFLD was associated with renal function impairment, even after adjustment for demographics and components of metabolic syndrome (OR = 2.85, 95%CI: 1.93-4.21, P = 0.000).

CONCLUSION

The biochemical indexes of NAFLD patients are significantly abnormal, and renal function impairment is associated with NAFLD. Patients with NAFLD should be regularly assessed for renal function to avoid progressing into chronic kidney disease and increasing the medical burden.

Comparison of three formulae for estimation of glomerular filtration rate in severely malnourished children at tertiary care facility

Objectives

First objective was to compare eGFR by Updated Schwartz (US) and Simple Height Independent (SHID) formula with Original Schwartz (OS) in children with Severe Acute Malnutrition (SAM). The second objective was to compare eGFR in children below and above two years.

Methods

This analytic study on estimation of GFR was based on retrospective data collected from 78 children with SAM at Nutritional Rehabilitation Unit from October 2014 - March 2015. Glomerular filtration rate was calculated using serum creatinine (S. Cr) and height in Original Schwartz, US and by age in SHID equation and compared with OS as standard. Data was analyzed using descriptive statistics.

Results

There were 78 children in this study. Males were 39(50%). Mean age of patients was 18±15.53 months with 62(79.48%) ≤24 months. Mean weight, height and Mid Upper Arm Cir-cumference was 5.69±2.42kg, 68.52+13.59 cm and 10±1.57 cm respectively. Mean eGFR by OS, US and SHID formula was 71.45±49.89, 58.06±3.91 and 59.33±3.73ml/min/1.73m2 respectively. There was significant difference (0.001) in mean eGFR calculated by three different formulae. Majority of children (73%) had subnormal GFR (<90 ml/min /1.73 m2). There was a significant difference in GFR ≥90ml calculated by US compared to OS (0.025) and by SHID with OS (0.04) in children below two years and no difference in children above two years. But there was no difference in other categories of eGFR calculated by either of formula in both age groups.

Conclusion

We found a significant difference in eGFR in ranges above 90 ml/min/1.73 m2 by US compared to OS as well as by SHID with OS in children below two years and no difference in children above two years. Also, there was no difference in GFR categories below 90 ml/min /1.73 m2 calculated by either of formula in both age groups. So, we may conclude that either of formula can be used in clinical practice for eGFR in mild to severe renal dysfunction in severely malnour-ished children.