Assessment Of Glomerular Filtration Rate Research Articles

Refining GFR estimation: a quest for the unobservable truth?

Assessing glomerular filtration rate (GFR), which is central to evaluating kidney health, remains challenging. Measured GFR is not widely available and lacks standardization. Estimated GFR can be highly inaccurate for some patients and has limited applicability to many patient populations, such as those who are acutely ill. Recent metabolomic advances show promise for identifying new filtration markers that might enhance GFR estimation. Improving GFR assessment will require refinement in both GFR measurement and estimation methods.

Toward Equitable Kidney Function Estimation in Critical Care Practice. Guidance From the Society of Critical Care Medicine's Diversity, Equity, and Inclusion in Renal Clinical Practice Task Force.

Accurate glomerular filtration rate (GFR) assessment is essential in critically ill patients. GFR is often estimated using creatinine-based equations, which require surrogates for muscle mass such as age and sex. Race has also been included in GFR equations, based on the assumption that Black individuals have genetically determined higher muscle mass. However, race-based GFR estimation has been questioned with the recognition that race is a poor surrogate for genetic ancestry, and racial health disparities are driven largely by socioeconomic factors. The American Society of Nephrology and the National Kidney Foundation (ASN/NKF) recommend widespread adoption of new "race-free" creatinine equations, and increased use of cystatin C as a race-agnostic GFR biomarker. Literature review and expert consensus. English language publications evaluating GFR assessment and racial disparities. We provide an overview of the ASN/NKF recommendations. We then apply an Implementation science methodology to identify facilitators and barriers to implementation of the ASN/NKF recommendations into critical care settings and identify evidence-based implementation strategies. Last, we highlight research priorities for advancing GFR estimation in critically ill patients. Implementation of the new creatinine-based GFR equation is facilitated by low cost and relative ease of incorporation into electronic health records. The key barrier to implementation is a lack of direct evidence in critically ill patients. Additional barriers to implementing cystatin C-based GFR estimation include higher cost and lack of test availability in most laboratories. Further, cystatin C concentrations are influenced by inflammation, which complicates interpretation. The lack of direct evidence in critically ill patients is a key barrier to broad implementation of newly developed "race-free" GFR equations. Additional research evaluating GFR equations in critically ill patients and novel approaches to dynamic kidney function estimation is required to advance equitable GFR assessment in this vulnerable population.

Assay validation and determination of the reference interval for symmetric dimethylarginine in healthy rabbits

BackgroundChronic kidney disease (CKD) is common in older rabbits. The renal biomarkers blood urea and creatinine can be insensitive as indicators of renal disease in rabbits. Symmetric dimethylarginine (SDMA) has been shown to be an earlier and more sensitive biomarker for the assessment of glomerular filtration rate and the evaluation of CKD in several animal species. An immunoassay for SDMA has been validated in a number of species. The purpose of this study was to validate the SDMA immunoassay for rabbit serum and plasma and to determine the normal rabbit reference interval (RI) for SDMA. MethodsClinically healthy rabbits (n=167) between 5 months and 8 years of age, of any breed or sex, participated in the study. Heparinized plasma or serum was collected for clinical chemistry and used for assay validation. Analytical validation of the SDMA immunoassay for rabbit serum and plasma was performed and included assessment of assay accuracy, precision, analytical sensitivity, linearity, interference testing, and plasma/ serum bias. The SDMA reference interval (RI) was determined. ResultsThe SDMA immunoassay met all set quality requirements assessed in analytical validation. The RI for SDMA was determined to be between 4 - 18 µg/dL. Conclusions and clinical relevanceThe SDMA immunoassay demonstrated acceptable performance in both rabbit serum and heparinized plasma as determined by the validation criteria. Although the utility of SDMA as a biomarker of renal disease in rabbits has not been determined, validation of the SDMA immunoassay should facilitate evaluation of SDMA levels in rabbits with confirmed renal disease.

Hyperfiltration can be detected by transcutaneous assessment of glomerular filtration rate in diabetic obese mice

tGFR measurement is a relatively new method to assess kidney function in conscious rodents, which can be repeated multiple times in the same animal to track the course of the disease and/or the effect of potential treatments. Since the literature was inconclusive on the suitability of this technique in obese mice, we validated it for the first time against classical plasma clearance in the commonly used BTBR ob/ob mouse model.

Conditional power and information fraction calculations at an interim analysis for random coefficient models.

Random coefficient (RC) models are commonly used in clinical trials to estimate the rate of change over time in longitudinal data. Trials utilizing a surrogate endpoint for accelerated approval with a confirmatory longitudinal endpoint to show clinical benefit is a strategy implemented across various therapeutic areas, including immunoglobulin A nephropathy. Understanding conditional power (CP) and information fraction calculations of RC models may help in the design of clinical trials as well as provide support for the confirmatory endpoint at the time of accelerated approval. This paper provides calculation methods, with practical examples, for determining CP at an interim analysis for a RC model with longitudinal data, such as estimated glomerular filtration rate (eGFR) assessments to measure rate of change in eGFR slope.

Is symmetric dimethylarginine superior to creatinine for assessing glomerular filtration rate for cats with kidney disease?

PICO Question Is symmetric dimethylarginine (SDMA) superior to creatinine for assessing glomerular filtration rate (GFR) for cats with chronic kidney disease?   Clinical bottom line Category Diagnosis.   Number and type of studies reviewed: The literature searches returned four relevant papers that answered this PICO. Three of the studies were retrospective diagnostic test studies, and one was a randomised, controlled, unblinded study.   Strength of evidence Moderate.   Outcomes reported Three out of the four studies analysed found that there was no significant difference between the correlation between symmetric dimethylarginine (SDMA) and glomerular filtration rate (GFR) and creatinine (sCr) and GFR, whilst the other identified a stronger correlation between SDMA and GFR. Two papers also evaluated the sensitivity and specificity of SDMA compared to creatinine. One paper found a similar sensitivity for both biomarkers and a significantly higher specificity for creatinine using the upper reference interval of 18 µg/dL for SDMA and 155.6 µmol/L (1.76 mg/dL) sCr, whilst the other found SDMA to have a superior sensitivity and both biomarkers to have a similar specificity using the upper reference interval of 14 µg/dL for SDMA and 185.64 µmol/L (2.1 mg/dL) for sCr.   Conclusions In view of the strength of evidence we conclude that the majority of the studies analysed do not demonstrate that SDMA is superior to creatinine for the assessment of GFR in cats with chronic kidney disease. More research is needed with larger sample sizes to investigate this further. Standardisation of the upper reference intervals across studies for creatinine and SDMA would be advantageous for comparison of sensitivity and specificity in future studies.   How to apply this evidence in practice The application of evidence into practice should take into account multiple factors, not limited to: individual clinical expertise, patient’s circumstances and owners’ values, country, location or clinic where you work, the individual case in front of you, the availability of therapies and resources. Knowledge Summaries are a resource to help reinforce or inform decision making. They do not override the responsibility or judgement of the practitioner to do what is best for the animal in their care.

Accuracy-Based Glomerular Filtration Rate Assessment by Plasma Iohexol Clearance in Kidney Transplant Donors.

An accurate measurement of the glomerular filtration rate (GFR) is essential for detecting renal insufficiency in living kidney donors. Iohexol is a "near-ideal" exogenous filtration marker for GFR measurements that has attracted increasing interest in clinical practice because it is non-toxic, non-radioactive, readily available, and easy to measure. In this study, we aimed to set up a laboratory test to conveniently assess the plasma clearance of iohexol in living kidney donors. A workflow was established in the institution's infusion clinic to administer iohexol and to collect three timed blood samples from renal transplant donors. Iohexol was thereafter measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The serum proteins were precipitated and the supernatant containing iohexol was diluted prior to the LC-MS/MS analysis. The LC-MS/MS method was developed on a Thermo Vanquish UHPLC coupled with a TSQ Endura triple quadruple mass spectrometer with a total run time of 2.5 min. The analytical performance of the method was assessed. The LC-MS/MS method demonstrated a good analytical performance. To calculate the iohexol clearance rate and the GFR, automated data integration and a result calculation were accomplished by using a custom Python script. Automated result reporting was achieved using a laboratory informatics system (LIS) vendor's direct media interface. We developed and implemented a laboratory test to assess the plasma clearance of iohexol. A workflow was established in the hospital to reliably measure the GFR in living kidney donors, with a potential to be further expanded into other areas where an accurate GFR measurement is needed.

Évaluation post-transplantation précoce de la dysfonction aiguë du greffon rénal

AbstractKidney transplantation is the best option in the treatment of end-stage kidney disease. Early acute kidney transplant dysfunction is a common complication that corresponds to acute renal failure (AKI) postoperatively after renal transplantation. When it occurs, it favors acute rejection and chronic dysfunction of kidney transplant. Incidence of this complication is constantly rising due to the increased use of grafts from extended criteria donors and from donors after circulatory death. This acute renal failure clinically results in a persistent elevation of serum creatinine and possibly a decrease in diuresis and the need for dialysis during the first postoperative week. However, these signs of renal damage are mostly inefficient and lead to a late diagnosis, limiting treatment efficiency. Therefore, it is essential to develop and use new methods for evaluating acute renal damage early after kidney transplantation. This review explores the various established or developing diagnostic modalities for early AKI after kidney transplantation, whether glomerular filtration rate (GFR) assessment methods or other approaches.

Serum cystatin C level can be used to estimate GFR in patients with solid tumors: PRO

An accurate assessment of glomerular filtration rate (GFR) is a fundamental aspect of cancer care and research. Recent studies have demonstrated that, in patients with solid tumors, GFR estimation based on serum creatinine combined with serum cystatin C presented minimal bias compared to measured GFR, may reduce race disparity when applied to race free GFR estimating equations, and improve the prediction of carboplatin clearance.

#2537 EPIDEMIOLOGY OF CHRONIC KIDNEY DISEASE IN THE REPUBLIC OF UZBEKISTAN

Abstract Background and Aims Chronic kidney disease (CKD) is an emerging global health problem, currently affecting up to 15% of the global adult population, and is independently associated with an increased risk of cardiovascular disease (CVD) similar to that of diabetes mellitus or coronary artery disease. heart [Reddy K.S., Shah B., Varghese S., Ramados A. 2005; 366: 1744-1749]. To assess the epidemiological characteristics of the development of CKD in the Republic of Uzbekistan (RUz) for 2020. Method The object of the study is the database of the Republican Specialized Scientific and Practical Medical Center for Nephrology and Kidney Transplantation of the Republic of Uzbekistan. Results According to the Institute of Health and Medical Statistics of the Ministry of Health of the Republic of Uzbekistan, the number of patients with end-stage renal disease (ESRD) decreased between 2011 and 2015. However, according to the data for 2020, the number of patients with stage 5 CKD reached 23,773 thousand and its increase is expected. The proportion of patients with chronic renal failure older than 18 years was registered 21,003 thousand in 2011 and 19,149 thousand in 2015, in those years there was a decrease. However, according to the national registry for 2020, CKD cases in the Republic of Uzbekistan, identified in all regions, amounted to 118026, there were 23773 patients with chronic renal failure receiving hemodialysis - 5149. The number of registered patients with CKD in the Autonomous Republic of Karakalpakstan was 9013, with CRF - 912, in need of hemodialysis - 115, receiving hemodialysis - 98, in need of transplantation - 21. In Andijan region, 416 persons were registered, with CRF - 201, in need of replacement therapy 137, receiving dialysis - 137, needing in transplantation - 11. In the Bukhara region, 4500 such patients were registered, CKD - 501, in need of substitution therapy - 172, receiving dialysis - 164 and in need of transplantation - 36. Conclusion With a general increase in the prevalence of CKD in the Republic of Uzbekistan in the dynamics of 2020, there is an improvement in the quality of diagnosing complications at earlier stages, at a later age and with a longer duration of CKD. Advances in the management of patients with CKD in recent years do not reduce the risk of end-stage chronic renal failure, but delay its development. Pronounced interregional differences in the frequency of registration of CKD in the database indicate problems in diagnosing CKD in a number of regions where the standard for examining patients with CKD with a mandatory assessment of glomerular filtration rate (GFR) and albuminuria at least once a year is not met.

P469 UP TO 12 MONTH TRENDS IN CLINICAL AND BIOCHEMICAL PARAMETERS AFTER SGLT2I THERAPY IN PATIENTS AFFECTED BY HEART FAILURE PATIENTS WITH REDUCED EJECTION FRACTION

Abstract Background The type–2 sodium–glucose cotransporters inhibitors (SGLT2i) are a new relevant therapeutic option for patients affected by chronic heart failure with reduced ejection fraction (HFrEF). The aim of this study was to evaluate the effects of SGLT2i on some clinical and biochemical parameters as well as the persistence of SGLT2i therapy up to 12 months. Methods We evaluated the consecutive patients affected by HFrEF in whom the SGLT2i therapy was prescribed since December 2021. The patients were followed–up after 1, 3, 6 and 12 months with a clinical visit, ECG, echocardiography, assessment of sodium, potassium, fasting glucose, hemoglobin, hematocrit and glomerular filtration rate (GFR) by creatinine. The data were analyzed by linear mixed models. Results Ninety patients were enrolled (age 60±9 years, 83% males, 20% diabetics, 38% affected by ischemic cardiomyopathy, NYHA class 2.24±0.43, 98% with ACEi/ARB/ARNi, 99% with beta–blockers, 84% with mineralcorticoid receptor antagonists). During the follow–up SGLT2i therapy was well tolerated in most of the patients. Five patients withdrew the therapy, 2 for hypotension, 2 for poor adherence, 1 for genital infection. As shown in the Figure, after SGLT2i therapy a significant reduction in weight and fasting glucose and a slight increase in LVEF were observed. Systolic arterial pressure did not show significant differences. As expected a significant short–term reduction in estimated GFR occurred, associated with a reduction of sodium serum levels. Hemoglobin and hematocrit progressively and significantly increased during follow–up. Conclusions In this “real world” study, among patients with HFrEF, the administration of SGLT2i resulted well tolerated in most of the patients. It was associated with the improvement of metabolic parameters (weight and fasting glucose), a slight temporary reduction in GFR, an increase in hemoglobin and systolic function. These data further support the use of this therapeutic approach in routine clinical practice.

Individualized assessment of glomerular filtration rate in clinical routine

Die valide Erfassung der Nierenfunktion mit Schätzformeln kann aufgrund sehr unterschiedlicher klinischer Patientenprofile herausfordernd sein, da manche Patientencharakteristika die zugrunde liegenden Biomarker stark beeinflussen. Warum bedarf es einer individualisierten Bestimmung der glomerulären Filtrationsrate (GFR), und wie kann diese aussehen? Beschreibung der relevanten GFR-Schätzformeln, ihrer Vor- und Nachteile, der endogenen Biomarker sowie der gemessenen GFR-Methoden, basierend auf der aktuellen Literatur und Expertenmeinung. Schätzformeln, wie z. B. die CKD-EPI(Chronic Kidney Disease Epidemiology Collaboration)- oder die EKFC(European Kidney Function Consortium)-Formel, verwenden als Biomarker zur Bestimmung der GFR entweder Serumkreatinin, Cystatin C oder die Kombination aus beidem. Für die Wahl des Biomarkers ist es wichtig, den Einfluss der „Non-GFR-Determinanten“ zu verstehen. Bei der Interpretation der geschätzten GFR („estimated GFR“, eGFR) ist es sinnvoll, die Akkuratheit zu beachten, denn es handelt sich hier nicht um eine exakte Zahl, sondern um einen eGFR-Bereich. In klinischen Szenarien, wo eine möglichst akkurate GFR gefordert ist (Nierenlebendspende, Medikamentendosierung), kann die mithilfe exogener Marker (Iohexol, Iothalamat) gemessene GFR eine geeignetere Methode sein. Individualisierte Therapieansätze setzen auch eine individualisierte Diagnostik voraus. Neben der gängigen Methode der Kreatinin-basierten eGFR zur Bestimmung der Nierenfunktion sollten in Abhängigkeit von den individuellen Patienteneigenschaften auch Cystatin-C-Schätzformeln oder die gemessene GFR bevorzugt werden, insbesondere wenn eine möglichst akkurate GFR-Bestimmung vonnöten ist.

Современные маркеры определения функциональной способности почек в урологической практике.

Introduction. Over the past decade, there has been a progressive increase in the number of patients with chronic kidney disease (CKD). Early diagnosis of renal insufficiency allows to prevent irreversible consequences leading to disability and significant medical and economic costs. Purpose: to analyze modern markers for determining the functional ability of the kidneys. Materials and methods. A search was carried out in PubMed and Library, according to the keywords creatinine, urea, glomerular filtration rate (GFR), clearance, formulas for calculating creatinine clearance, cystatin C, β2-microglobulin, β-bound protein, NGAL, KIM-1, chronic kidney disease, chronic renal failure, urolithiasis. We found 389 sources no older than 10 years (published after 2012) that were relevant to the topic of the review. 80 articles were selected directly for citation in the review. Results. GFR assessment and detection of albuminuria are the most effective methods, but biomarkers used to calculate GFR are subject to a number of factors and do not allow assessing kidney function in real time. For early prediction of acute renal injury, the most suitable biomarkers are considered to be: NGAL and KIM-1 and IL-18. Equations combining cystatin C and creatinine r work better than equations using only cystatin C or creatinine, especially in situations where it is necessary to confirm chronic kidney disease. The combination of creatinine, cystatin C and the ratio of urine albumin to creatinine improves the stratification of the risk of progression of kidney disease and mortality. The latest developments in biomarkers allow us to hope that in the near future the assessment of the functional ability of the kidneys will be carried out in real time and will become a general clinical practice of a modern doctor. Conclusion. Modern biomarkers of the functional ability of the kidneys allow not only to evaluate the function, but also to screen for diseases, conduct differential diagnosis, and evaluate the effectiveness of the treatment. The modern approach to the diagnosis of renal dysfunction should be based not only on its diagnosis, but also on determining the topic of nephron damage.

Secretory Phospholipase A2 and Interleukin-6 Levels as Predictive Markers of the Severity and Outcome of Patients with COVID-19 Infections

Coronavirus disease (COVID-19) has become a global pandemic. COVID-19 patients need immediate diagnosis and rehabilitation, which makes it urgent to identify new protein markers for a prognosis of the severity and outcome of the disease. The aim of this study was to analyze the levels of interleukin-6 (IL-6) and secretory phospholipase (sPLA2) in the blood of patients regarding the severity and outcome of COVID-19 infection. The study included clinical and biochemical data obtained from 158 patients with COVID-19 treated at St. Petersburg City Hospital No. 40. A detailed clinical blood test was performed on all patients, as well as an assessment of IL-6, sPLA2, aspartate aminotransferase (AST), total protein, albumin, lactate dehydrogenase (LDH), APTT, fibrinogen, procalcitonin, D-dimer, C-reactive protein (CRB), ferritin, and glomerular filtration rate (GFR) levels. It was found that the levels of PLA2, IL-6, APTV, AST, CRP, LDH, IL-6, D-dimer, and ferritin, as well as the number of neutrophils, significantly increased in patients with mild to severe COVID-19 infections. The levels of IL-6 were positively correlated with APTT; the levels of AST, LDH, CRP, D-dimer, and ferritin; and the number of neutrophils. The increase in the level of sPLA2 was positively correlated with the levels of CRP, LDH, D-dimer, and ferritin, the number of neutrophils, and APTT, and negatively correlated with the levels of GFR and lymphocytes. High levels of IL-6 and PLA2 significantly increase the risk of a severe course by 13.7 and 2.24 times, and increase the risk of death from COVID-19 infection by 14.82 and 5.32 times, respectively. We have shown that the blood levels of sPLA2 and IL-6 increase in cases which eventually result in death and when patients are transferred to the ICU (as the severity of COVID-19 infection increases), showing that IL-6 and sPLA2 can be considered as early predictors of aggravation of COVID-19 infections.

Measuring Creatinine Clearance Is the Most Accurate Way for Calculating the Proper Continuous Infusion Meropenem Dose for Empirical Treatment of Severe Gram-Negative Infections among Critically Ill Patients

Assessment of glomerular filtration rate (GFR) is necessary for dose adjustments of beta-lactam that are excreted by the kidneys, such as meropenem. The aim of this study was to compare the daily dose of 24 h-continuous infusion (CI) meropenem when GFR was calculated by means of measured creatinine clearance (mCLCR) or estimated by the CKDEPI (eGFRCKDEPI), Cockcroft-Gault (eGFRCG), and MDRD (eGFRMDRD) equations. Adult critically ill patients who underwent therapeutic drug monitoring (TDM) for the assessment of 24 h-CI meropenem steady state concentration (Css) and for whom a 24 h-urine collection was performed were retrospectively enrolled. Meropenem clearance (CLM) was regressed against mCLCR, and meropenem daily dose was calculated based on the equation infusion rate = daily dose/CLM. eGFRCKDEPI, eGFRCG, and eGFRCKDEPI were regressed against mCLCR in order to estimate CLM. Forty-six patients who provided 133 meropenem Css were included. eGFRCKDEPI overestimated mCLCR up to 90 mL/min, then mCLCR was underestimated. eGFRCG and eGFRMDRD overestimated mCLCR across the entire range of GFR. In critically ill patients, dose adjustments of 24 h-CI meropenem should be based on mCLCR. Equations for estimation of GFR may lead to gross under/overestimates of meropenem dosages. TDM may be highly beneficial, especially for critically ill patients with augmented renal clearance.

Interpretation of Estimated Glomerular Filtration Rate

Glomerular filtration rate (GFR) plays an important role in the clinical evaluation of renal function, classification, prognosis prediction, and drug dosing in patients with acute or chronic kidney disease . Estimated GFR (eGFR) is calculated based on endogenous filtration markers, such as creatinine and cystatin C. These are useful markers, but it is necessary to understand the clinical settings in which eGFR, calculated using creatinine or cystatin C, may be less accurate. Several equations, including the Cockcroft and Gault, modification of diet in renal disease, and chronic kidney disease-epidemiology collaboration (CKD-EPI) equations, are used to calculate eGFR. The latter is most common because it has high accuracy and can predict prognosis. Recently, a new race-omitting CKD-EPI equation has been developed but further studies are required to determine whether it can be applied in clinical practice and research. Furthermore, careful use of eGFR is needed in acute kidney injury, kidney transplantation, and dialysis patients. Drug dosing must be guided by accurate GFR assessment. In addition to medical care, GFR assessment is also important for public health and research. Therefore, further studies are needed to reevaluate and develop the equations for accurate eGFR calculations.

Cystatin C–Based Equation to Estimate GFR without the Inclusion of Race and Sex

BackgroundThe accuracy of estimation of kidney function with the use of routine metabolic tests, such as measurement of the serum creatinine level, has been controversial. The European Kidney Function Consortium (EKFC) developed a creatinine-based equation (EKFC eGFRcr) to estimate the glomerular filtration rate (GFR) with a rescaled serum creatinine level (i.e., the serum creatinine level is divided by the median serum creatinine level among healthy persons to control for variation related to differences in age, sex, or race). Whether a cystatin C–based EKFC equation would increase the accuracy of estimated GFR is unknown.MethodsWe used data from patients in Sweden to estimate the rescaling factor for the cystatin C level in adults. We then replaced rescaled serum creatinine in the EKFC eGFRcr equation with rescaled cystatin C, and we validated the resulting EKFC eGFRcys equation in cohorts of White patients and Black patients in Europe, the United States, and Africa, according to measured GFR, levels of serum creatinine and cystatin C, age, and sex.ResultsOn the basis of data from 227,643 patients in Sweden, the rescaling factor for cystatin C was estimated at 0.83 for men and women younger than 50 years of age and 0.83+0.005×(age–50) for those 50 years of age or older. The EKFC eGFRcys equation was unbiased, had accuracy that was similar to that of the EKFC eGFRcr equation in both White patients and Black patients (11,231 patients from Europe, 1093 from the United States, and 508 from Africa), and was more accurate than the Chronic Kidney Disease Epidemiology Collaboration eGFRcys equation recommended by Kidney Disease: Improving Global Outcomes. The arithmetic mean of EKFC eGFRcr and EKFC eGFRcys further improved the accuracy of estimated GFR over estimates from either biomarker equation alone.ConclusionsThe EKFC eGFRcys equation had the same mathematical form as the EKFC eGFRcr equation, but it had a scaling factor for cystatin C that did not differ according to race or sex. In cohorts from Europe, the United States, and Africa, this equation improved the accuracy of GFR assessment over that of commonly used equations. (Funded by the Swedish Research Council.)

PS-C14-12: RIGHT VENTRICLE SYSTOLIC FUNCTION IN HYPERTENSIVE NEPHROPATHY PATIENTS

Objective: To investigate right ventricular systolic function in chronic kidney disease (CKD) patients. Design and method: We examined 15 essential hypertensive subjects and 34 untreated non-diabetic essential hypertensive patients with II and III stage of hypertensive CKD. Echocardiography and ambulatory blood pressure (BP) monitoring was performed for all patients. Glomerular filtration rate (GFR) assessment was based on CKD-EPI formula. Patients underwent a two-dimensional Doppler-coupled echocardiography with determination of right ventricular (RV) systolic function with conventional echocardiographic methods: RV fractional area change, Tricuspid Annular Plane of Systolic Excursion (TAPSE), Tricuspid annular S’ velocity of the lateral tricuspid annulus, RV Tei index. Right ventricle free wall longitudinal strain (RVFWLS) obtained by speckle-tracking. Results: CKD patients and essential hypertensive subjects had no significant difference between RV systolic function values evaluated with RV fractional area change and RV Tei index. At the same time we observed significantly lower values of TAPSE and Tricuspid annular S’ velocity of the lateral tricuspid annulus (p < 0.05 in both cases) in CKD patients. Highly significant RVFWLS decline was observed in CKD patients comparing to essential hypertensive subjects (p < 0.01). In univariate correlation analysis GFR was more closely related to RVFWLS (r = 0,523, p < 0.01) comparing to Tricuspid annular S’ velocity of the lateral tricuspid annulus and TAPSE (r = 0,371, p < 0.05 and r = 0,293, p < 0.05 respectively). Conclusion: Hypertensive nephropathy patients have early impairment of RV systolic function detected by significantly lower Tricuspid annular S’ velocity as well as TAPSE and highly significant RVFWLS decline comparing to essential hypertensive subjects. There was more significant relationship between GFR and RVFWLS rather than Tricuspid annular S’ velocity of the lateral tricuspid annulus and TAPSE.

Evaluation of Kidney Function in Patients with COVID-19 at the Epidemiological Treatment Centre in CHNU Fann

Alteration of renal function during SARS-CoV-2 infection is frequent and is associated with excess mortality. It is multifactorial, involving mechanisms more specific to COVID-19: viral invasion, endothelitis and thrombosis, activation of the renin-angiotensin-aldosterone system, and elevation of pro-inflammatory cytokines. Thus, the objective of this work was to assess renal function in patients with moderate and severe forms of COVID-19. This was a prospective cross-sectional study of patients with COVID-19. The parameters studied were age, sex, uremia, creatinine and glomerular filtration rate (GFR). All biological parameters were measured with the A15 Biosystems automated system (Barcelona, Spain) and the GFR was calculated according to the MDRD formula. Data processing was carried out with the SPSS (Statistical Package for Social Sciences) software version 23. Our study population consisted of 192 subjects with COVID-19, of which 111 were moderate and 81 were severe. The mean age of our subjects was 60 years and a sex ratio of 1.02. GFR assessment showed that 28% of the population had a lowered GFR (2). Analysis of the results according to the clinical forms showed frequencies of 19% of disturbance of renal function for the moderate forms against 40% for the severe forms. Impaired renal function appears to be frequent in patients with severe SARS-CoV-2 infection and is associated with a bad prognosis. Any patient hospitalized with SARS-CoV-2 should benefit from an initial nephrological assessment which could be used as a marker to dictate the prognosis of the severity of COVID-19.

Glomerular Filtration Rate Assessment in Children.

Glomerular filtration rate (GFR) measurement is a key tool for determining the degree of chronic kidney disease. The assessment of GFR is even more challenging in children than in adults with more variables in the equation than race and sex. Monitoring the progress of the kidney disease can therefore be difficult as in the initial stages of a decline in kidney function, there are no clinical signs. Due to children's growth and development, changes in muscle mass and growth impair GFR estimation based solely on serum creatinine values. More invasive methods of GFR measurement are more reliable, but techniques using ionising agents, requiring large volume blood samples or timed voiding, have limited application in children. This paper reviews the methods of measuring and determining glomerular filtration rate and kidney function in children.