Prevention programmes of progressive renal disease in developing nations (Review Article)

Probiotics mitigate kidney damage after exposure to Sri Lanka's local groundwater from chronic kidney disease with uncertain etiology (CKDu) prevalent area in zebrafish

Groundwater in Sri Lanka, contaminated with environmental toxins, is suspected to potentially induce chronic kidney disease of uncertain etiology (CKDu) in humans. This study aims to elucidate the potential mitigating effects of probiotics on kidney damage induced by exposure to this local groundwater (LW) in zebrafish. We used zebrafish as a model organism and exposed them to local groundwater to evaluate the risk of CKDu. Probiotics were then added at a concentration of 108 colony-forming units per milliliter (CFU/mL). Our findings revealed that exposure to local groundwater resulted in abnormalities, such as tail deletion and spinal curvature in zebrafish larvae. However, the addition of probiotics mitigated these effects, improving the hatching rate, heart rate, length, weight, deformity rate, survival rate, and abnormal behavior of zebrafish. It also positively influenced the differential expression levels of kidney development and immunity-related genes (dync2h1, foxj1, pkd2, gata3, slc20a1, il1β, and lyso). Furthermore, exposure to LW decreased both the diversity and abundance of microbiota in zebrafish larvae. However, treatment with probiotics, such as L. plantarum and L. rhamnosus partially restored the disrupted gut microbiota and significantly impacted the cellular process pathways of the microbial community, as determined by KEGG (Kyoto Encyclopedia of Genes and Genomes) analysis. In conclusion, this study highlights the risks associated with Sri Lanka's local groundwater from a CKDu prevalent area and confirms the beneficial effects of different probiotics. These findings may provide new insights into bacterial function in host kidney health.

Quality of life and associated factors among chronic kidney disease patients at Zewditu Memorial and Tikur Anbessa Specialised Hospitals, Ethiopia: a cross-sectional study design

INTRODUCTION

Chronic kidney disease (CKD) is associated with significant morbidity, mortality, healthcare cost and reduced health-related quality of life (HRQoL). This study aimed to assess HRQoL and associated factors among patients with CKD at both Zewditu Memorial and Tikur Anbessa Specialised Hospitals, Ethiopia.

METHOD

A cross-sectional study design was performed. All patients who visited the renal clinics in both hospitals from March to July 2019 were targeted, and data were collected using interviews and medical records. HRQoL was assessed using the Kidney Disease and Quality of Life-36 tool. Normality assessment was done for HRQoL subscales. Descriptive statistics, logistic regression, t-test and one-way analysis of variance were performed.

RESULT

A total of 300 patients with CKD were included. Around 62% of them were in either stage 3 or 4 CKD. The mean domain scores of physical component summary (PCS), mental component summary (MCS), burden of kidney disease, effect of kidney disease and symptoms and problems of kidney disease (SPKD) subscales were 50.4, 59.5, 63.1, 74.6 and 80.4, respectively. The lowest HRQoL was seen in the PCS scale, while the highest was in SPKD. In addition, the study revealed that a lower level of education, elevated serum creatinine and a history of smoking were significantly associated with poor PCS score. Further, the presence of three or more comorbidities, CKD-related complications and a lower haemoglobin level were significantly associated with poor MCS.

CONCLUSION

The overall mean scores of PCS and MCS were low, below the standard level. Level of education, serum creatinine and smoking history were significantly associated with PCS, while the presence of comorbidity, complications and haemoglobin level were significantly associated with MCS. Stakeholders working on CKD management should design a relevant strategy targeting patients, patients' care providers and healthcare professionals to improve HRQoL of patients.

Multi-pronged research on endemic chronic kidney disease of unknown etiology in Sri Lanka: a systematic review

Increasing prevalence of endemic chronic kidney disease of unknown etiology (CKDu) in Sri Lanka is a major health problem since the 1990s. Despite numerous studies on CKDu, research groups have been unable to develop a comprehensive approach to mitigate the disorder, and thereby to identify research gaps. We conducted a systematic literature review of 119 publications on CKDu in Sri Lanka from Pubmed, Google Scholar, and Scopus, published until end September 2020. A higher CKDu prevalence in the working population of the North Central Province was reported with recent studies indicating patients from non-endemic regions as well. A majority were etiological studies that recorded conflicting and inconclusive evidence on CKDu etiology. Studies on clinico-pathological, diagnostic, biochemical, and molecular biological aspects of CKDu, studies analyzing CKDu symptom burden, anthropological, and behavioral impacts of CKDu, were reviewed as well. A dearth of research exists on nutritional, demographical, immunological, and microbial aspects of CKDu. The overview of the reviewed literature indicated the absence of a comprehensive plan of action to mitigate this situation. Hence, we propose the "One Health" approach with a systems dynamics model as a potential way forward to alleviate the CKDu epidemic in Sri Lanka. This enables the representation of multiple causative agents (and interactions thereof) among environmental, animal, and human systems, in concert with the "exposome" that provides the totality of exposure the individual has undergone since birth.

Accelerometry Correlates in Body Composition, Physical Fitness, and Disease Symptom Burden: A Pilot Study in End-Stage Renal Disease

There is strong evidence that hemodialysis (HD) patients with a sedentary lifestyle have a higher risk of death compared to peers who engage in regular physical activity. Therefore, monitoring physical activity is of utmost importance. However, there is a lack of data on objectively measured physical activity behaviors in HD patients. Therefore, this study aimed to objectively measure physical activity in HD patients throughout the week, with particular attention to dialysis and non-dialysis days. We also examined how objectively measured physical activity correlated with physical fitness, body composition, and disease burden. Daily physical activity, body composition, serum parameters, comorbidity index, sit-to-stand, and hand-grip strength tests were measured in 14 HD patients. Daily physical activity was measured using the Actigraph GT9X accelerometer. The Dialysis Symptom Index questionnaire was also used. We found significant differences in anthropometric variables (weight, body mass index, overhydration, lean tissue index, and fat tissue index, all p < 0.05) and phase angle (p < 0.01) between HD patients reaching and patients not reaching physical activity guidelines for patients with chronic diseases. HD patients showed to be less active during dialysis days compared to non-dialysis days as indicated in sedentary time (-11.7%; p = 0.001), light (-47.3%; p = 0.003), moderate (-51.5%; p = 0.001), moderate to vigorous (-49.3%; p = 0.001), and vigorous (-34.3%; p = 0.067) physical activity. No significant correlations were found among serum parameters, symptom burden, and comorbidity burden, but a very large and positive correlation was found between phase angle and total moderate to vigorous physical activity (p < 0.01). Our findings support the need to implement physical activity on dialysis days in HD units to mitigate the effects of sedentary behavior. Prospective, long-term studies evaluating the use of accelerometers in HD patients and their effects on physical activity are needed.

End-stage kidney disease and rationing of kidney replacement therapy in the free state province, South Africa: a retrospective study

Background

End-stage kidney disease (ESKD) and the required kidney replacement therapy (KRT) are significant public health challenges for low-and-middle-income countries. The South African government adopted a KRT rationing policy to balance the growing need for KRT and scarce resources. We aimed to describe the epidemiology and KRT access in patients with ESKD referred to the main public sector hospital in the Free State Province, South Africa.

Methods

A retrospective study of adult patients with ESKD admitted to Universitas Academic Hospital for KRT, was conducted between 1 January 2016 and 31 December 2018. A review of the KRT committee decisions to offer or deny KRT based on the KRT rationing policy of the Free State was undertaken. Demographic information, KRT committee outcomes, laboratory test results, and clinical details were collected from assessment tools, KRT committee meeting diaries, and electronic hospital records.

Results

Of 363 patients with ESKD referred for KRT access, 96 with incomplete records were excluded and 267 were included in the analysis. Median patient age was 40 (interquartile range, 33‒49) years, and male patients accounted for 56.2 % (150/267, p = 0.004) of the cohort. The average annual ESKD incidence was 49.9 (95 % confidence interval [CI], 35.8‒64.0) per-million-population. The most prevalent comorbidities were hypertension (42.3 %; 113/267), human immunodeficiency virus (HIV) (28.5 %; 76/267), and diabetes mellitus (19.1 %; 51/267). The KRT access rate was 30.7 % (82/267), with annual KRT incidence rates of 8.05 (95 % CI, 4.98‒11.1), 11.5 (95 % CI, 7.83‒15.1), and 14.1 (95 % CI, 10.3‒18.0) per-million-population in 2016, 2017, and 2018, respectively. Advanced organ dysfunction was the commonest reason recorded for KRT access denial (58.9 %; 109/185). Age (odds ratio [OR], 1.04; 95 % CI, 1.00‒1.07; p = 0.024) and diabetes (OR, 5.04; CI, 1.69‒15.03; p = 0.004) were independent predictors for exclusion from KRT, while hypertension (OR, 1.80; 1.06‒3.04; p = 0.029) independently predicted advanced organ dysfunction resulting in KRT exclusion.

Conclusions

Non-communicable and communicable diseases, including hypertension, diabetes, and HIV, contributed to ESKD, highlighting the need for improved early prevention strategies to address a growing incidence rate. Two-thirds of ESKD patients were unable to access KRT, with age, diabetes mellitus, and advanced organ dysfunction being significant factors adversely affecting KRT access.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-021-02387-x.

Exploring the Root Cause for Chronic Kidney Disease of Unknown Etiology (CKDu) via Analysis of Metal Ion and Counterion Contaminants in Drinking Water: A Study in Sri Lanka

The introduction of elevated amounts of foreign ions into the blood may lead to impairment of the filtration membrane of kidneys and chronic kidney damage. In order to assess the risk of consumption of drinking water (dug well water) in chronic kidney disease of unknown etiology (CKDu), affected areas in Sri Lanka, trace metals, and other counterions in water samples obtained from dug wells were analyzed and compared with a reference area. Drinking water could be the major source that is responsible for entering nephrotoxic ion contaminants into the human body. To achieve the objective, drinking water samples were collected from dug wells in two CKDu endemic areas and a reference area where no CKDu patients were found in a dry season. In the Wewelketiya area (one of the endemic areas), Cd concentrations in 60% of water samples and Pb concentrations in 40% of water samples have exceeded the maximum limit given by Sri Lanka water quality standards. Fluoride concentrations also have exceeded the permissible limits of more than 80% of collected water samples in both CKDu endemic areas. However, none of the water samples in reference areas has reported that Cd, Pb, and fluoride are beyond their maximum permissible limits. Hence, people in the particular CKDu endemic areas are at risk of kidney tissue damage due to long-term exposure to drinking water with elevated levels of some metal ions and counterions.

Markers and risk factors for chronic kidney disease in sub-Saharan Africans: baseline levels and 12-month trajectories in newly referred patients in Cameroon

Background

Little is known about the changes in disease makers and risk factors in patients with chronic kidney disease (CKD) under nephrological care in Africa. This study aimed to evaluate the baseline level of markers of CKD and their 12-month time-trend in newly referred patients in a tertiary hospital in Cameroon.

Methods

This was a retrospective cohort study including 420 patients referred for CKD between 2006 and 2012 to the nephrology unit of the Douala General Hospital in the littoral region of Cameroon. Their disease and risk profile was assessed at baseline and every 3 months for 1 year. Estimated glomerular filtration rate (eGFR) was based on MDRD and Schwartz equations. CKD was diagnosed in the presence of eGFR< 60 ml/min/1.73 m² and/or proteinuria> 1+ and/or abnormal renal ultrasound persisting for ≥3 months. Data analysis used mixed linear regressions.

Results

Of the 420 patients included, 66.9% were men and mean age was 53.8 (15.1) years. At referral, 37.5% of the participants were at CKD Stage 3, 30.8% at stage 4 and 26.8% at stage 5. There was 168 (40%) diabetic and 319 (75.9%) hypertensive patients. After some improvement during the first 3 months, eGFR steadily decreased during the first year of follow-up, and this pattern was robust to adjustment for many confounders. Systolic and diastolic blood pressure levels significantly fluctuated during the first twelve months of follow-up. Changes in the levels of other risk factors and markers of disease severity over time were either borderline or non-significant.

Conclusion

Patients with CKD in African settings are referred to the nephrologist at advanced stages. This likely translates into a less beneficial effects of specialised care on the course of the disease.

Circulating microRNAs as potential biomarkers of chronic kidney disease

Chronic kidney disease (CKD) is a supra - nosological term that reflects the progressive nature of chronic kidney diseases, which are based on the mechanisms of nephrosclerosis. Diagnosis of CKD at the earliest stages is of great importance, because it allows, by using therapeutic agents, to slow the progression of renal dysfunction and the development of cardiovascular complications. However, the currently available methods for diagnosing renal function impairment, including the determination of endogenous creatinine clearance, can detect renal dysfunction too late, when around 40-50% of the renal parenchyma is already reversibly or irreversibly damaged. In this regard, there is an active search for new, more sensitive and specific biomarkers for early diagnosis of CKD. Recent studies in cellular and animal models of CKD have demonstrated the important role of microRNA, a new class of posttranscriptional regulators of gene expression, in physiology and pathophysiology of kidneys. In particular, it has been shown that their expression profile in blood or urine can reflect changes in cells involved in a particular pathological process, since these cells can secrete a specific population of microRNAs, for example, through secretion of microRNA-containing exosomes. This gave grounds for considering increased or decreased expression of individual microRNAs in renal tissue or biological fluids (including urine) as new biomarkers for the diagnosis and monitoring of CKD. This review presents the results of recent experimental and clinical studies on these issues.

The First Report on the Frequency of Asymptomatic Proteinuria in Iranian School-aged Children

Background

Proteinuria is a well-known indicator of renal dysfunction. In this study, we evaluated the frequency of proteinuria in a sample of healthy Iranian elementary school students using both dipsticks and urine albumin-to-creatinine ratio (UACR) methods.

Materials and Methods

This cross-sectional study was performed on 478 school students aged 7-9 years who were selected by multistage random cluster sampling from Isfahan city, Iran. A clean midstream first-morning urine sample was obtained from each subject. Urine samples were examined by dipstick method, and accordingly, they were reported as negative; trace; 1+; 2+; 3+; and 4+. UACR was determined in samples with positive dipstick proteinuria (defined as trace or greater).

Results

This study included 478 students (42.8% boys), with mean age of 7.0 ± 0.4 years. Positive dipstick was detected in 124 (25.9%) cases. The frequency of positive dipstick proteinuria was significantly higher in the girls than boys (29.6% vs. 20.9%, respectively; P = 0.04). In cases with a positive dipstick, 10 (2.1%) cases had UACR 30-300 mg/g. The frequency of UACR of 30-300 mg/g was 1.4% and 2.5% in boys and girls, respectively. There was no significant difference in the frequency of UACR 30-300 mg/g in terms of gender (P = 0.4). None of the subjects had UACR above 300 mg/g.

Conclusion

While the frequency of asymptomatic proteinuria varies widely across different studies, we found a higher rate of proteinuria in Iranian children. Cost-effectiveness analyses are needed to justify large screening program for detecting asymptomatic proteinuria, as a cardinal manifestation of kidney disease, in Iranian children.

Comparison of visceral, body fat indices and anthropometric measures in relation to chronic kidney disease among Chinese adults from a large scale cross-sectional study

Background

The aim of the study was to assess the association between chronic kidney disease (CKD) and obesity in predicting CKD among Chinese adults, distinguishing between 5 different adiposity indices: visceral fat index (VFI), percentage body fat (PBF), body mass index (BMI), waist circumference (WC) and waist-to-height ratio (WHtR).

Methods

A total of 29,516 participants aged 35 years or above were selected using a stratified multistage random sampling method across China during 2012–2015. CKD was defined as an estimated glomerular filtration (eGFR) < 60 ml/min/1.72m².

Results

The overall weighted prevalence of CKD was 3.94% (3.62% in males and 4.25% in females). All five adiposity indices had significant negative correlations to eGFR (P < 0.05). The area under the ROC (receiver operating characteristic) curves (AUC) for PBF was almost significantly larger than the other adiposity indices (P < 0.001). In addition, PBF yielded the highest Youden index in identifying CKD (male: 0.15; female: 0.20). In the logistic analysis, PBF had the highest crude odds ratios (ORs) in both males (OR: 1.819, 95% CI 1.559–2.123) and females (OR: 2.268, 95% CI 1.980–2.597). After adjusted for age, smoking status, alcohol use, education level, marital status, rural vs. urban area, geographic regions, and diagnosis of hypertension, diabetes mellitus, myocardial infarction and stroke, the ORs on PBF remained significant for both genders (P < 0.05).

Conclusions

Obesity is associated with an increased risk of CKD. Furthermore, PBF was a better predictor for identifying CKD than other adiposity indices (BMI, WC, WHtR, and VFI).

Electronic supplementary material

The online version of this article (10.1186/s12882-018-0837-1) contains supplementary material, which is available to authorized users.

Detection of a Peptide Biomarker by Engineered Yeast Receptors

Directed evolution of membrane receptors is challenging as the evolved receptor must not only accommodate a non-native ligand, but also maintain the ability to transduce the detection of the new ligand to any associated intracellular components. The G-protein coupled receptor (GPCR) superfamily is the largest group of membrane receptors. As members of the GPCR family detect a wide range of ligands, GPCRs are an incredibly useful starting point for directed evolution of user-defined analytical tools and diagnostics. The aim of this study was to determine if directed evolution of the yeast Ste2p GPCR, which natively detects the α-factor peptide, could yield a GPCR that detects Cystatin C, a human peptide biomarker. We demonstrate a generalizable approach for evolving Ste2p to detect peptide sequences. Because the target peptide differs significantly from α-factor, a single evolutionary step was infeasible. We turned to a substrate walking approach and evolved receptors for a series of chimeric intermediates with increasing similarity to the biomarker. We validate our previous model as a tool for designing optimal chimeric peptide steps. Finally, we demonstrate the clinical utility of yeast-based biosensors by showing specific activation by a C-terminally amidated Cystatin C peptide in commercially sourced human urine. To our knowledge, this is the first directed evolution of a peptide GPCR.

Incidence, Development, and Prognosis of Diabetic Kidney Disease in China: Design and Methods

Background:

Although that glomerulonephritis is the major cause of end-stage renal disease in developing countries such as China, the increasing prevalence of diabetes has contributed to the changing spectrum of predialysis chronic kidney disease. Recent studies have revealed an increased proportion of patients with diabetic kidney disease (DKD) in hemodialysis populations in large cities in China. However, studies regarding the clinical phenotype of DKD in China are extremely limited. The incidence, development, and prognosis of diabetic kidney disease (INDEED) study aims to investigate the incidence, progression, and prognosis of DKD, as well as the associated genetic, behavioral, and environmental factors and biomarkers in patients with DKD in China.

Methods:

INDEED study is a prospective cohort study based on all participants with diabetes in the Kailuan study, which is a general population-based cohort study in northern China. Altogether, over 10,000 participants with diabetes will be followed biennially. Questionnaires documenting general characteristics, behavioral and environmental factors, and medical history will be administrated. Anthropometric measurements and a series of laboratory tests will be performed in one central laboratory. The DNA, plasma, and urine samples of every participant will be stored in a biobank for future research.

Conclusions:

INDEED study will provide essential information regarding the clinical phenotype and prognosis of patients with DKD in China and will be valuable to identify factors and biomarkers associated with patients with DKD in China.

Drinking water quality and chronic kidney disease of unknown etiology (CKDu): synergic effects of fluoride, cadmium and hardness of water

High prevalence of chronic kidney disease of unknown etiology (CKDu) in some regions of the world is suspected mainly due to a toxin-mediated renal failure. We examined the incidence of CKDu and potable chemical water quality in a CKDu-affected region. This region has been identified as a high-risk zone for CKDu (location: latitude: 8.3500°-9.0000°, longitude: 80.3833°-81.3000°, North Central Province, NCP, Sri Lanka) by the World Health Organization (WHO). However, within this macro-region, small pockets of CKDu non-prevalence zones do exist; notably, the residents in those pockets consume spring water. Therefore, the drinking water quality of four areas, namely high-CKDu-prevalence areas (zone I), low-CKDu-prevalence area (zone II), the CKDu-free isolated pockets (zone III) and control areas (controls) were examined for F, Al, Cd, and As, and hardness and the statistical analysis were carried out to probe possible correlations among these parameters. The fluoride and hardness concentrations of water in zone III and control areas are much lower compared to zones I and II, and the water hardness is ~61 mg/L CaCO3. In zones I and II, the harness of drinking water is ~121-180 mg/L CaCO3; however, Al, Cd and As concentrations are almost comparable and below WHO recommendations. In most of the locations in zones I and II, the F concentration in drinking water is higher than the WHO recommendations. The peculiar distribution patterns of CKDu point to a synergic effect of trace elements in water for etiology of the disease.

The impact of aluminum, fluoride, and aluminum-fluoride complexes in drinking water on chronic kidney disease

It is suspected that drinking water containing fluoride and aluminum results in negative health effects especially on brain, liver, and kidney. In this investigation, the effect of F, Al, and AlFx complex on chronic kidney disease (CKD) was investigated. Mice were treated either with WHO recommended or slightly higher F and Al levels in drinking water. Treatment solutions contained 0.05-10.0 mg/L of F, 0.08-10.0 mg/L of Al, or 0.07-15 mg/L of AlFx, and the treatment period was 42 weeks. Blood urea level and creatinine levels were investigated as a measure of malfunction of kidneys. Histopathological evaluations of kidney tissues were carried out to assess the extent of damage that F, Al, and AlFx complex could cause. It was demonstrated that the treated drinking water containing F and Al with par with WHO or moderately above the WHO levels or AlFx in low level (0.07-15 mg/L) does not lead to CKD in mice.

Sickle cell trait is not associated with chronic kidney disease in adult Congolese patients: a clinic-based, cross-sectional study

OBJECTIVE

The aim of this study was to evaluate the determinants of chronic kidney disease (CKD) with special emphasis on sickle cell trait (SCT).

METHODS

Three hundred and fifty-nine patients (171 men and 188 women), aged 18 years or older, with reduced kidney function (eGFR < 90 ml/min/1.73 m(2)) and seen at secondary and tertiary healthcare in Kinshasa were consecutively recruited in this cross-sectional study. Serum creatinine and haemoglobin electrophoresis were performed in each patient. CKD was defined as < 60 ml/min/1.73 m(2). Logistic regression analysis was used to assess determinants of CKD with a special emphasis on SCT. A p-value < 0.05 defined the level of statistical significance.

RESULTS

SCT was present in 19% of the study population; its frequency was 21 and 18% (p > 0.05) in patients with and without CKD, respectively. In multivariate analysis, sickle cell trait was not significantly (OR: 0.38; 95% CI: 0.559-1.839; p = 0.235) associated with CKD; the main determinants were dipstick proteinuria (OR: 1.86; 95% CI: 1.094-3.168; p = 0.02), the metabolic syndrome (OR: 1.69; 95% CI: 1.033-2.965; p = 0.03), haemoblobin ≥ 12 g/dl (OR: 0.36; 95% CI: 0.210-0.625; p = 0.001), and personal history of hypertension (OR: 2.16; 95% CI: 1.202-3.892; p = 0.01) and of diabetes mellitus (OR: 2.35; 95% CI: 1.150-4.454; p = 0.001).

CONCLUSION

SCT was not an independent determinant of CKD in the present case series. Traditional risk factors emerged as the main determinants of CKD.

Efficacy and safety of Shenyankangfu tablets for primary glomerulonephritis: study protocol for a randomized controlled trial

BACKGROUND

Chronic kidney disease is a common disease. Most chronic kidney diseases evolve from primary glomerulonephritis. Proteinuria is an independent risk factor for the progression of chronic kidney disease. The general consensus is that therapy administered to decrease proteinuria should include steroids and/or immunosuppressants, angiotensin-converting enzyme inhibitors, and angiotensin II receptor blockers. However, the side effects of, and adverse reactions to, these agents reduce the benefits to patients. In addition, the cost of these drugs is relatively high. Therefore, identification of inexpensive and effective drugs to decrease proteinuria is urgently needed. Shenyankangfu tablets have been a widely applied Chinese patent medicine for many years to decrease proteinuria. However, there is a lack of research-derived data regarding the clinical use. Therefore, we designed the present randomized controlled clinical trial to compare the efficacy and safety of Shenyankangfu tablets versus losartan potassium for control of proteinuria in patients with primary glomerulonephritis.

METHODS/DESIGN

This study will be a multicenter, prospective, double-blind, double-dummy, randomized controlled clinical trial. We will enroll 720 patients diagnosed with primary glomerulonephritis. The eligible patients will be randomly divided into the following groups at a 1:1:1:1:1 ratio: Shenyankangfu tablets group, losartan potassium 50 mg group, losartan potassium 100 mg group, Shenyankangfu tablets + losartan potassium 50 mg group, and Shenyankangfu tablets + losartan potassium 100 mg group. All groups will be followed up for 48 weeks; follow-up visits will be performed, at weeks 0, 4, 8, 12, 24, 36, and 48. The primary efficacy outcome will be the post-treatment change in the 24-hour proteinuria level, and the secondary efficacy outcomes will be the post-treatment changes in the serum creatinine level, estimated glomerular filtration rate, traditional Chinese medicine syndrome score, and serum albumin level.

DISCUSSION

The results of this trial will provide solid data for use in evidence-based medicine with respect to the efficacy and safety of Shenyankangfu tablets for control of proteinuria in patients with primary glomerulonephritis compared to those of losartan potassium. Moreover, we infer that therapy comprising Shenyankangfu tablets + losartan potassium can decrease proteinuria to a larger extent than Shenyankangfu tablets or losartan potassium can alone.

TRIAL REGISTRATION

This trial was registered on 12 February 2014 at ClinicalTrials.gov (ID number NCT02063100).

Increased risk of end-stage renal disease among hip fracture patients

BACKGROUND

Inflammation-related microvasculr disease, albuminuria, and rapid deterioration of renal function can accelerate the development of end-stage renal disease (ESRD). The role of hip fracture (HFr), a disorder that involves inflammation, in the development of ESRD has not been fully investigated. This study explored whether HFr increases the risk of ESRD.

METHODS

Taiwan National Health Insurance inpatient claims were used to identify 83,550 patients newly diagnosed with HFr from 2000 to 2006, and 83,550 age- and sex-matched patients without HFr were randomly selected for comparison. Hazards of ESRD combined with HFr, comorbidities, including hypertension, hyperlipidemia, peripheral arterial disease, osteoporosis and asthma, and general health status, with Charlson comorbidity index (CCI), were assessed using data to the end of 2011.

RESULTS

ESRD risk was 1.42-fold higher (95% confidence interval [CI]:1.29-1.33) in the HFr cohort than in the control group, which was computed using the Cox proportional model. Age-specific analysis revealed that the adjusted hazard ratios (aHRs) of ESRD for HFr patients increased slightly as age increased, with an aHR of 1.56 (95% CI:1.35-1.81) for patients 65-74 years old, which gradually decreased to 0.88 (95% CI:0.66-1.18) for patients ≥ 85 years old. ESRD risk increased as HFr severity increased, with an aHR of 6.71 (95% CI:5.90-7.63) for patients with severe HFr.

CONCLUSION

This study is the first to report that HFr, in combination with underlying osteoporosis-related chronic illness, microvascular disease and chronic inflammation, is associated with an increased risk of ESRD, particularly among relatively younger people.

The epidemiology of chronic kidney disease in sub-Saharan Africa: a systematic review and meta-analysis

BACKGROUND

Amid rapid urbanisation, the HIV epidemic, and increasing rates of non-communicable diseases, people in sub-Saharan Africa are especially vulnerable to kidney disease. Little is known about the epidemiology of chronic kidney disease (CKD) in sub-Saharan Africa, so we did a systematic review and meta-analysis examining the epidemiology of the disease.

METHODS

We searched Medline, Embase, and WHO Global Health Library databases for all articles published through March 29, 2012, and searched the reference lists of retrieved articles. We independently reviewed each study for quality. We used the inverse-variance random-effects method for meta-analyses of the medium-quality and high-quality data and explored heterogeneity by comparing CKD burdens across countries, settings (urban or rural), comorbid disorders (hypertension, diabetes, HIV), CKD definitions, and time.

FINDINGS

Overall, we included 90 studies from 96 sites in the review. Study quality was low, with only 18 (20%) medium-quality studies and three (3%) high-quality studies. We noted moderate heterogeneity between the medium-quality and high-quality studies (n=21; I(2)=47·11%, p<0·0009). Measurement of urine protein was the most common method of determining the presence of kidney disease (62 [69%] studies), but the Cockcroft-Gault formula (22 [24%] studies) and Modification of Diet in Renal Disease formula (17 [19%] studies) were also used. Most of the studies were done in urban settings (83 [93%] studies) and after the year 2000 (57 [63%] studies), and we detected no significant difference in the prevalence of CKD between urban (12·4%, 95% CI 11-14) and rural (16·5%, 13·8-19·6) settings (p=0·474). The overall prevalence of CKD from the 21 medium-quality and high-quality studies was 13·9% (95% CI 12·2-15·7).

INTERPRETATION

In sub-Saharan Africa, CKD is a substantial health burden with risk factors that include communicable and non-communicable diseases. However, poor data quality limits inferences and draws attention to the need for more information and validated measures of kidney function especially in the context of the growing burden of non-communicable diseases.

FUNDING

Duke University.

Economic Burden of Incident Unplanned Starts on Peritoneal Dialysis in a High Specialty Health Care Facility in Mexico City

OBJECTIVES

Few studies have examined hospitalization costs for unplanned initiation of peritoneal dialysis (PD). We used data from a health care facility in Mexico to examine first hospitalization costs associated with the unplanned initiation of PD.

METHODS

Descriptive analyses focusing on initial hospitalization costs during the unplanned initiation of PD were conducted. In addition, multivariate regression models examined the association of costs with requiring urgent hemodialysis (HD) at the time of starting PD, and the association of driving distance with requiring urgent HD.

RESULTS

Of 195 patients hospitalized in 2010 for PD catheter placement, 51 patients met criteria for unplanned PD initiation and 25 of them required urgent HD prior to PD initiation. Ninety-two percent of the patients received 90% or greater government subsidy of hospital costs. Average inpatient costs for the first hospitalization related to the unplanned initiation of PD were 64,174 Mexican Pesos (MXN) (US $4,657). Costs were 78,683 MXN ($5,710) per patient for those requiring urgent HD and 50,225 MXN ($3,645) for those who did not, a difference (P<0.05) of roughly 28,000 MXN ($2,032), and regression results were similar. In addition, long driving distance to the institution was significantly associated with requiring urgent HD.

CONCLUSIONS

Our findings highlight potential cost savings to payers for developing better strategies to manage PD starts in Mexico and should help inform policy regarding oversight and coverage of low-income patients at risk of dialysis.

Effect of multidisciplinary pre-dialysis education in advanced chronic kidney disease: Propensity score matched cohort analysis

AIM

  The mortality and morbidity of end-stage renal failure patients remains high despite recent advances in pre-dialysis care. Previous studies suggesting a positive effect of pre-dialysis education were limited by unmatched comparisons between the recipients and non-recipients of education. The present study aimed to clarify the roles of the multidisciplinary pre-dialysis education (MPE) in chronic kidney disease patients.

METHODS

  We performed a retrospective single centre study, enrolling 1218 consecutive pre-dialysis chronic kidney disease patients, between July 2007 and Feb 2008 and followed them up to 30 months. By using propensity score matching, we matched 149 recipient- and non-recipient pairs from 1218 patients. The incidences of renal replacement therapy, mortality, cardiovascular event and infection were compared between recipients and non-recipients of MPE.

RESULTS

  Renal replacement therapy was initiated in 62 and 64 patients in the recipients and non-recipients, respectively (P > 0.05). The MPE reduced unplanned urgent dialysis (8.7% vs 24.2%, P < 0.001) and shortened hospital days (2.16 vs 5.05 days/patient per year). MPE recipients had a better metabolic status at the time of initiating renal replacement therapy. Although no significant survival advantage from MPE was exhibited, MPE recipients had lower incidence of cardiovascular events (adjusted hazard ratio, 0.24; 95% confidence interval (CI), 0.08 to 0.78; P = 0.017), and a tendency toward a lower infection rate (adjusted hazard ratio, 0.44; 95% CI, 0.17 to 1.11; P = 0.083).

CONCLUSION

  MPE was associated with better clinical outcomes in terms of urgent dialysis, cardiovascular events and infection.

Effects of exercise on kidney function among non-diabetic patients with hypertension and renal disease: randomized controlled trial

Background

Chronic kidney disease is an important public health threat. Such patients present high morbidity and mortality due to cardiovascular disease, with low quality of life and survival, and also high expenditure resulting from the treatment. Arterial hypertension is both a cause and a complication of kidney disease; also, arterial hypertension is a risk factor for cardiovascular disease among patients with kidney diseases. There is some evidence that exercise interventions may be beneficial to chronic kidney disease patients, but previous studies included only end-stage patients, i.e. those undergoing dialysis. This study aims to evaluate the effect of exercise on kidney function, quality of life and other risk factors for cardiovascular disease among non-diabetic chronic hypertensive kidney disease patients who are not undergoing dialysis.

Methods

The participants will be located through screening hypertensive patients attended within the public healthcare network in Pelotas, a city in south of Brazil. Eligible individuals will be those with glomerular filtration rate between 15 and 59 ml/min x 1.73 m². The randomization will be done in fixed-size blocks of six individuals such that 75 participants will be allocated to each group. At baseline, information on demographic, socioeconomic, behavioral, anthropometric, blood pressure and quality-of-life variables will be collected, and laboratory tests will be performed. The intervention will consist of three weekly physical exercise sessions lasting 60–75 minutes each, with a total duration of 16 weeks. The outcomes will be the kidney function progression rate, quality of life, blood pressure, lipid profile, hemoglobin level, ultrasensitive C-reactive protein level, and ankle-arm index. The patients in both groups (intervention and control) will be reassessed and compared partway through the study (8^th week), at the end of the intervention (16^th week) and in the 8^th week after the end of the intervention.

Discussion

There is still a scarcity of data relating to the effect of physical exercise among the most numerous group of individuals with kidney disease, i.e. patients undergoing conservative treatment. In particular, there is a lack of randomized controlled studies. This study will help fill this gap.

Analysis of urinary microRNAs in chronic kidney disease

Kidney biopsy is the gold-standard diagnostic test for intrinsic renal disease, but requires hospital admission and carries a 3% risk of major complications. Current non-invasive prognostic indicators such as urine protein quantification have limited predictive value. Better diagnostic and prognostic tests for chronic kidney disease patients are a major focus for industry and academia, with efforts to date directed largely at urinary proteomic approaches. microRNAs constitute a recently identified class of endogenous short non-coding single-stranded RNA oligonucleotides that regulate gene expression post-transcriptionally. Quantification of urinary microRNAs offers an alternative approach to the identification of chronic kidney disease biomarkers.

Radiographic periodontal bone loss in chronic kidney disease

BACKGROUND

We examined the extent and severity of radiographic periodontal bone loss in patients with different stages of chronic kidney disease (CKD) and explored a potential dose-response relationship between bone loss and CKD-related biomarkers.

METHODS

Panoramic radiographs were obtained from 129 CKD patients (78 males and 51 females; mean age: 63.5 years, range: 24 to 91 years), including 63 patients undergoing dialysis for an average of 3.3 years (range: 0.5 to 14 years). Glomerular filtration rate (GFR), dialysis dose, and levels of serum biomarkers were obtained through a hospital database. Interproximal bone loss was assessed as a percentage of root length.

RESULTS

Twenty-nine participants were edentulous (23.8% of those on dialysis versus 21.2% of those with residual kidney function; χ(2) test, P = 0.724). The extent of bone loss was higher among dialysis patients (analysis of variance [ANOVA], P = 0.007), but no clear dose-response association between CKD stage and extent was evident. GFR, dialysis dose, and levels of serum biomarkers did not differ between edentulous and dentate individuals, and only serum albumin was lower in patients with extensive bone loss (ANOVA, P = 0.030). After adjusting for dialysis status, the severity of bone loss was positively associated with glucose levels (multiple regression, P = 0.019) and white blood cell count (P = 0.032), whereas the number of teeth present was positively associated with plasma phosphorus (P = 0.008) and negatively with glucose levels (P = 0.011).

CONCLUSION

Despite a higher extent of bone loss in dialysis patients, the lack of a dose-response association between bone loss and CKD stage or the levels of CKD-related serum biomarkers underscores the complex relationship between the two conditions.

The contribution of chronic kidney disease to the global burden of major noncommunicable diseases

Noncommunicable diseases (NCDs) are the most common causes of premature death and morbidity and have a major impact on health-care costs, productivity, and growth. Cardiovascular disease, cancer, diabetes, and chronic respiratory disease have been prioritized in the Global NCD Action Plan endorsed by the World Health Assembly, because they share behavioral risk factors amenable to public-health action and represent a major portion of the global NCD burden. Chronic kidney disease (CKD) is a key determinant of the poor health outcomes of major NCDs. CKD is associated with an eight- to tenfold increase in cardiovascular mortality and is a risk multiplier in patients with diabetes and hypertension. Milder CKD (often due to diabetes and hypertension) affects 5-7% of the world population and is more common in developing countries and disadvantaged and minority populations. Early detection and treatment of CKD using readily available, inexpensive therapies can slow or prevent progression to end-stage renal disease (ESRD). Interventions targeting CKD, particularly to reduce urine protein excretion, are efficacious, cost-effective methods of improving cardiovascular and renal outcomes, especially when applied to high-risk groups. Integration of these approaches within NCD programs could minimize the need for renal replacement therapy. Early detection and treatment of CKD can be implemented at minimal cost and will reduce the burden of ESRD, improve outcomes of diabetes and cardiovascular disease (including hypertension), and substantially reduce morbidity and mortality from NCDs. Prevention of CKD should be considered in planning and implementation of national NCD policy in the developed and developing world.

Chronic kidney diseases of uncertain etiology (CKDue) in Sri Lanka: geographic distribution and environmental implications

The increase in the number of chronic kidney disease (CKD) patients from the north central region of Sri Lanka has become a environmental health issue of national concern. Unlike in other countries where long-standing diabetes and hypertension are the leading causes of renal diseases, the majority of CKD patients from this part of Sri Lanka do not show any identifiable cause. As the disease is restricted to a remarkably specific geographical terrain, particularly in the north central dry zone of the country, multidisciplinary in-depth research studies are required to identify possible etiologies and risk factors. During this study, population screening in the prevalent region and outside the region, analysis of geoenvironmental and biochemical samples were carried out. Population screening that was carried out using a multistage sampling technique indicated that the point prevalence of CKD with uncertain etiology is about 2-3% among those above 18 years of age. Drinking water collected from high-prevalent and non-endemic regions was analyzed for their trace and ultratrace element contents, including the nephrotoxic heavy metals Cd and U using ICP-MS. The results indicate that the affected regions contain moderate to high levels of fluoride. The Cd contents in drinking water, rice from affected regions and urine from symptomatic and non-symptomatic patients were much lower indicating that Cd is not a contributing factor for CKD with uncertain etiology in Sri Lanka. Although no single geochemical parameter could be clearly and directly related to the CKD etiology on the basis of the elements determined during this study, it is very likely that the unique hydrogeochemistry of the drinking water is closely associated with the incidence of the disease.

Dose-dependent Na and Ca in fluoride-rich drinking water--another major cause of chronic renal failure in tropical arid regions

Endemic occurrence of chronic kidney disease with unknown etiology is reported in certain parts of the north central dry zone of Sri Lanka and has become a new and emerging health issue. The disease exclusively occurs in settlements where groundwater is the main source of drinking water and is more common among low socio-economic groups, particularly among the farming community. Due to its remarkable geographic distribution and histopathological evidence, the disease is believed to be an environmentally induced problem. This paper describes a detailed hydrogeochemical study that has been carried out covering endemic and non-endemic regions. Higher fluoride levels are common in drinking water from both affected and non-affected regions, whereas Ca-bicarbonate type water is more common in the affected regions. In terms of the geochemical composition of drinking water, affected households were rather similar to control regions, but there is a large variation in the Na/Ca ratio within each of the two groups. Fluoride as shown in this study causes renal tubular damage. However it does not act alone and in certain instances it is even cytoprotective. The fine dividing line between cytotoxicity and cytoprotectivity of fluoride appears to be the effect of Ca(2+) and Na(+) of the ingested water on the F(-) metabolism. This study illustrates a third major cause (the other two being hypertension and diabetes) of chronic kidney diseases notably in tropical arid regions such as the dry zone of Sri Lanka.

Early recognition and prevention of chronic kidney disease

Chronic kidney disease is a common disorder and its prevalence is increasing worldwide. Early diagnosis on the basis of presence of proteinuria or reduced estimated glomerular filtration rate could permit early intervention to reduce the risks of cardiovascular events, kidney failure, and death that are associated with chronic kidney disease. In developed countries, screening for the disorder is most efficient when targeted at high-risk groups including elderly people and those with concomitant illness (such as diabetes, hypertension, or cardiovascular disease) or a family history of chronic kidney disease, although the role of screening in developing countries is not yet clear. Effective strategies are available to slow the progression of chronic kidney disease and reduce cardiovascular risk. Treatment of high blood pressure is recommended for all individuals with, or at risk of, chronic kidney disease. Use of angiotensin-converting-enzyme inhibitors or angiotensin-receptor blockers is preferred for patients with diabetic chronic kidney disease or those with the proteinuric non-diabetic disorder. Glycaemic control can help prevent the onset of early stages of chronic kidney disease in individuals with diabetes. Use of statins and aspirin is beneficial for most patients with chronic kidney disease who are at high cardiovascular risk, although research is needed to ascertain how to best prevent cardiovascular disease in this cohort. Models of care that facilitate delivery of the many complex aspects of treatment simultaneously could enhance management, although effects on clinical outcomes need further assessment. Novel clinical methods to better identify patients at risk of progression to later stages of chronic kidney disease, including kidney failure, are needed to target management to high-risk subgroups.

Multidisciplinary predialysis education decreases the incidence of dialysis and reduces mortality--a controlled cohort study based on the NKF/DOQI guidelines

BACKGROUND

Observational studies have demonstrated that multidisciplinary predialysis education (MPE) improves the post-dialysis outcomes of chronic kidney disease (CKD) patients. However, the beneficial effect of MPE remains unclear in prospective controlled studies.

METHODS

All CKD patients who visited the outpatient nephrology clinics at two centres of the Chang Gung Memorial Hospital in 2006-07 were enrolled. The incidence of dialysis and mortality were compared between MPE recipients and non-recipients. The content of the MPE was standardized in accordance with the NKF/DOQI guidelines. Prognostic factors for progression to end-stage renal disease (ESRD) and all-cause mortality were analysed by using the Cox proportional hazards model.

RESULTS

Of 573 patients, 287 received MPE. Dialysis was initiated in 13.9% and 43% of the patients in the MPE and non-MPE groups, respectively (P < 0.001). The mean follow-up period was 11.7 +/- 0.9 months. The overall mortality was 1.7% and 10.1% in the MPE and non-MPE groups, respectively (P < 0.001). Cox regression analysis revealed that diabetes, estimated glomerular filtration rate (eGFR), high-sensitive C-reactive protein (hs-CRP) and MPE assignment were significant independent predictors for progression to ESRD. Independent prognostic factors for mortality included age, diabetes, eGFR, hs-CRP and MPE assignment.

CONCLUSIONS

MPE based on the NKF/DOQI guidelines may decrease the incidence of dialysis and reduce mortality in late-stage CKD patients.

Population-based screening for CKD

Organizations both in the United States and globally have advocated for screening for chronic kidney disease with a urine test for proteinuria followed by subsequent testing with creatinine-based estimated glomerular filtration rate determinations. Screening for a disease, such as chronic kidney disease, can have value, but a decision to screen is not a trivial decision. Criteria must be met to balance the aggregate benefits with the risks and costs of a screening test. We discuss how screening for chronic kidney disease meets many of these criteria, but also how the populations to which it is applied must be targeted and the strategies for testing must be clearly defined.