The relationship between the modified National Institute of Health activity and chronicity scoring system, and the long-term prognosis for lupus nephritis: A retrospective single-center study.

BACKGROUND: The revision of International Society of Nephrology/Renal Pathology Society (ISN/RPS) classification guidelines for lupus nephritis (LN) was suggested by a working group, who recommended a modified National Institute of Health (NIH) activity and chronicity scoring system to evaluate active and chronic LN lesions. However, whether this approach was useful for estimating long-term prognosis for LN patients is unclear. METHODS: We conducted a retrospective cohort study in Japanese subjects with biopsy-proven LN, between 1977 and 2018. Pathologic lesions were evaluated based on ISN/RPS 2003 classifications and the modified NIH scoring system. Patients were grouped by activity index (low, 0-5; moderate, 6-11; high, 12-24), and chronicity index (low, 0-2; moderate, 3-5; high, 6-12). The primary outcome was a composite of end-stage kidney disease (ESKD) or all-cause death, and the secondary outcome was ESKD alone. RESULTS: Sixty-six subjects with a median age of 31 years were included. During median follow-up (11.5 years), 15 patients reached the primary outcome: 10 had ESKD, four had died, and one had ESKD and died. Kaplan-Meier analysis showed that the cumulative primary outcome incidence increased with a higher chronicity index (log-rank trend p < 0.001). From multivariable survival analysis, moderate (hazard ratio [HR] 6.17, 95% confidence interval [CI] 1.14 to 33.20; p = 0.034) and high chronicity indices (HR 20.20, 95% CI 1.13 to 359.82; p = 0.041) were risk factors for the primary outcome. CONCLUSION: Moderate and high chronicity indices were associated with an increased ESKD risk for LN.

Grading system utilising the total score of Oxford classification for predicting renal prognosis in IgA nephropathy.

The Oxford classification of IgA nephropathy (IgAN) can evaluate each MEST-C score individually. We analysed a new grading system that utilised the total MEST-C score in predicting renal prognosis. Altogether, 871 IgAN patients were classified into three groups using the new Oxford classification system (O-grade) that utilised the total MEST-C score (O-grade I: 0-1, II: 2-4, and III: 5-7 points), and the 10-year renal prognosis was analysed. The clinical findings became significantly severer with increasing O-grades, and the renal survival rate by the Kaplan-Meier method was 94.1%, 86.9%, and 74.1% for O-grades I, II, and III, respectively. The hazard ratios (HRs) for O-grades II and III with reference to O-grade I were 2.8 (95% confidence interval [CI] 1.3-6.0) and 6.3 (95% CI 2.7-14.5), respectively. In the multivariate analysis, mean arterial pressure and eGFR, proteinuria at the time of biopsy, treatment of corticosteroids/immunosuppressors, and O-grade (HR 1.63; 95% CI 1.11-2.38) were the independent factors predicting renal prognosis. Among the nine groups classified using the O-grade and Japanese clinical-grade, the renal prognosis had an HR of 15.2 (95% CI 3.5-67) in the severest group. The O-grade classified by the total score of the Oxford classification was associated with renal prognosis.

Precision medicine approach to dialysis including incremental and decremental dialysis regimens.

PURPOSE OF REVIEW: Conventional standardization of haemodialysis for treatment of end-stage kidney disease (ESKD) is predicated upon the fixed construct of one disease stage and one patient category. Increasingly recognized are subgroups of patients for whom less-intensive haemodialysis, such as incremental or decremental haemodialysis, could be employed. RECENT FINDINGS: Almost 30% of patients with incident ESKD have clinical and residual kidney function (RFK) parameters that could accommodate less-intensive haemodialysis. In one study, patients with incident ESKD and substantial RKF treated with low-dose haemodialysis had similar mortality rate as those treated with standard-dose haemodialysis, adding to the evidence that endogenous kidney function -- when present -- can complement less-intensive haemodialysis schedules. Hazards related to incremental haemodialysis include insidious development of fluid overload and higher rates of fluid removal. Finally, deintensification of haemodialysis treatment could be employed in patients with ESKD who seek conservative care. SUMMARY: A shift in approach to ESKD from a dichotomous frame -- disease presence versus absence -- to stages of dialysis-dependent kidney disease, each stage associated with attuned haemodialysis intensity, has been proposed. Haemodialysis standardization and personalization -- often considered mutually exclusive -- can be combined in incremental haemodialysis. Data from ongoing and future randomized clinical trials, comparing less-intensive with standard haemodialysis schedules, are required to change practice.

Revisiting the association between human leukocyte antigen and end-stage renal disease.

Multiple works have studied possible associations between human leukocyte antigen (HLA) alleles and end stage renal disease (ESRD) showing, however, contradictory and inconsistent results. Here, we revisit the association between ESRD and HLA antigens, comparing HLA polymorphism (at HLA-A, -B, -C, -DRB1, -DQB1 and DQA1 loci) in ESRD patients (n = 497) and controls (n = 672). Our data identified several HLA alleles that displayed a significant positive or negative association with ESRD. We also determined whether heterozygosity or homozygosity of the ESRD-associated HLA alleles at different loci could modify the prevalence of the disease. Few HLA allele combinations displayed significant associations with ESRD, among which A*3_26 combination showed the highest strength of association (OR = 4.488, P≤ 0.05) with ESRD. Interestingly, the age of ESRD onset was not affected by HLA allele combinations at different loci. We also performed an extensive literature analysis to determine whether the association of HLA to ESRD can be similar across different ethnic groups. Our analysis showed that at least certain HLA alleles, HLA-A*11, HLA-DRB1*11, and HLA-DRB1*4, display a significant association with ESRD in different ethnic groups. The findings of our study will help in determining possible protective or susceptible roles of various HLA alleles in ESRD.

Reclassification of chronic kidney disease patients for end-stage renal disease risk by proteinuria indexed to estimated glomerular filtration rate: multicentre prospective study in nephrology clinics.

BACKGROUND: In non-dialysis chronic kidney disease (CKD), absolute proteinuria (Uprot) depends on the extent of kidney damage and residual glomerular filtration rate (GFR). We therefore evaluated, as compared with Uprot, the strength of association of proteinuria indexed to estimated GFR (eGFR) with end-stage renal disease (ESRD) risk. METHODS: In a multi-cohort prospective study in 3957 CKD patients of Stages G3-G5 referred to nephrology clinics, we tested two multivariable Cox models for ESRD risk, with either Uprot (g/24 h) or filtration-adjusted proteinuria (F-Uprot) calculated as Uprot/eGFR ×100. RESULTS: Mean ± SD age was 67 ± 14 years, males 60%, diabetics 29%, cardiovascular disease (CVD) 34%, eGFR 32 ± 13 mL/min/1.73 m2, median (interquartile range) Uprot 0.41 (0.12-1.29) g/24 h and F-Uprot 1.41 (0.36-4.93) g/24 h per 100 mL/min/1.73 m2 eGFR. Over a median follow-up of 44 months, 862 patients reached ESRD. At competing risk analysis, ESRD risk progressively increased when F-Uprot was 1.0-4.9 and ≥5.0 versus <1.0 g/24 h per 100 mL/min/1.73 m2 eGFR in Stages G3a-G4 (P < 0.001) and Stage G5 (P = 0.002). Multivariable Cox analysis showed that Uprot predicts ESRD in Stages G3a-G4 while in G5 the effect was not significant; conversely, F-Uprot significantly predicted ESRD at all stages. The F-Uprot model allowed a significantly better prediction versus the Uprot model according to Akaike information criterion. Net reclassification improvement was 12.2% (95% confidence interval 4.2-21.1), with higher reclassification in elderly, diabetes and CVD, as well as in diabetic nephropathy and glomerulonephritis, and in CKD Stages G4 and G5. CONCLUSIONS: In patients referred to nephrology clinics, F-Uprot predicts ESRD at all stages of overt CKD and improves, as compared with Uprot, reclassification of patients for renal risk, especially in more advanced and complicated disease.

BMI and its association with death and the initiation of renal replacement therapy (RRT) in a cohort of patients with chronic kidney disease (CKD).

BACKGROUND: A survival advantage associated with obesity has often been described in dialysis patients. The association of higher body mass index (BMI) with mortality and renal replacement therapy (RRT) in preterminal chronic kidney disease (CKD) patients has not been established. METHODS: Subjects were patients with pre-terminal CKD who were recruited to the CKD.QLD registry. BMI at time of consent was grouped as normal (BMI 18.5-24.9 kg/m2), overweight (BMI 25-29.9 kg/m2), mild obesity (BMI 30-34.9 kg/m2) and moderate obesity+ (BMI ≥ 35 kg/m2) as defined by WHO criteria. The associations of BMI categories with mortality and starting RRT were analysed. RESULTS: The cohort consisted of 3344 CKD patients, of whom 1777 were males (53.1%). The percentages who had normal BMI, or were overweight, mildly obese and moderately obese+ were 18.9, 29.9, 25.1 and 26.1%, respectively. Using people with normal BMI as the reference group, and after adjusting for age, socio-economic status, CKD stage, primary renal diagnoses, comorbidities including cancer, diabetes, peripheral vascular disease (PVD), chronic lung disease, coronary artery disease (CAD), and all other cardiovascular disease (CVD), the hazard ratios (HRs, 95% CI) of males for death without RRT were 0.65 (0.45-0.92, p = 0.016), 0.60 (0.40-0.90, p = 0.013), and 0.77 (0.50-1.19, p = 0.239) for the overweight, mildly obese and moderately obese+. With the same adjustments the hazard ratios for death without RRT in females were 0.96 (0.62-1.50, p = 0.864), 0.94 (0.59-1.49, p = 0.792) and 0.96 (0.60-1.53, p = 0.865) respectively. In males, with normal BMI as the reference group, the adjusted HRs of starting RRT were 1.15 (0.71-1.86, p = 0.579), 0.99 (0.59-1.66, p = 0.970), and 0.95 (0.56-1.61, p = 0.858) for the overweight, mildly obese and moderately obese+ groups, respectively, and in females they were 0.88 (0.44-1.76, p = 0.727), 0.94 (0.47-1.88, p = 0.862) and 0.65 (0.33-1.29, p = 0.219) respectively. CONCLUSIONS: More than 80% of these CKD patients were overweight or obese. Higher BMI seemed to be a significant "protective" factor against death without RRT in males but there was not a significant relationship in females. Higher BMI was not a risk factor for predicting RRT in either male or female patients with CKD.

Timing of Renal-Replacement Therapy in Patients with Acute Kidney Injury and Sepsis.

BACKGROUND: Acute kidney injury is the most frequent complication in patients with septic shock and is an independent risk factor for death. Although renal-replacement therapy is the standard of care for severe acute kidney injury, the ideal time for initiation remains controversial. METHODS: In a multicenter, randomized, controlled trial, we assigned patients with early-stage septic shock who had severe acute kidney injury at the failure stage of the risk, injury, failure, loss, and end-stage kidney disease (RIFLE) classification system but without life-threatening complications related to acute kidney injury to receive renal-replacement therapy either within 12 hours after documentation of failure-stage acute kidney injury (early strategy) or after a delay of 48 hours if renal recovery had not occurred (delayed strategy). The failure stage of the RIFLE classification system is characterized by a serum creatinine level 3 times the baseline level (or ≥4 mg per deciliter with a rapid increase of ≥0.5 mg per deciliter), urine output less than 0.3 ml per kilogram of body weight per hour for 24 hours or longer, or anuria for at least 12 hours. The primary outcome was death at 90 days. RESULTS: The trial was stopped early for futility after the second planned interim analysis. A total of 488 patients underwent randomization; there were no significant between-group differences in the characteristics at baseline. Among the 477 patients for whom follow-up data at 90 days were available, 58% of the patients in the early-strategy group (138 of 239 patients) and 54% in the delayed-strategy group (128 of 238 patients) had died (P=0.38). In the delayed-strategy group, 38% (93 patients) did not receive renal-replacement therapy. Criteria for emergency renal-replacement therapy were met in 17% of the patients in the delayed-strategy group (41 patients). CONCLUSIONS: Among patients with septic shock who had severe acute kidney injury, there was no significant difference in overall mortality at 90 days between patients who were assigned to an early strategy for the initiation of renal-replacement therapy and those who were assigned to a delayed strategy. (Funded by the French Ministry of Health; IDEAL-ICU ClinicalTrials.gov number, NCT01682590 .).

Incidence, Prevalence, and Duration of Chronic Kidney Disease in Taiwan: Results from a Community-Based Screening Program of 106,094 Individuals.

BACKGROUND/AIMS: Taiwan has the highest incidence of end-stage renal disease, which requires renal replacement therapy. Chronic kidney disease (CKD) contributes to this burden. However, the current data on the epidemiologic features of CKD in Taiwan are incomplete. Therefore, we aimed to investigate the prevalence and incidence of CKD in a population-based study and then estimate the average dwelling time (ADT) in the main clinical burden of CKD (stages 3-5). METHODS: A prospective cohort study was designed with an integrated community-based multiple screening program of 106,094 individuals aged ≥20 years in Keelung, Taiwan, in 1999-2009. Prevalence was estimated as the percentage of CKD stages among individuals attending the first screening, and incidence was expressed as the ratio of total desired events in the following period to the total observational time. Finally, ADT was estimated from the ratio of prevalence to incidence. RESULTS: The participants' mean age was 47.7 ± 15.4 years. The estimated prevalence was 15.46% for total CKD and 9.06% for CKD stages 3-5. The incidence was 27.21/1,000 person-years (PY) for total CKD and 16.89/1,000-PY for CKD stages 3-5. Older patients, males, and those patients with comorbidities of diabetes mellitus (DM), hypertension, and metabolic syndrome (MetS) exhibited higher prevalence and incidence rates than their opposing counterparts. Moreover, the ADT of CKD stages 3-5 was 5.37 years (95% CI 5.17-5.57). Males and those with comorbidities of DM or MetS had shorter ADTs in CKD stages 3-5 than their opposing counterparts. Interestingly, the ADT of participants with hypertension was longer than those without. CONCLUSIONS: The prevalence and incidence of CKD in Taiwan are high. Moreover, ADT in CKD stages 3-5 varied according to sex, age, and comorbidity. Further exploration of the factors associated with the shifting of this duration will shed light on effective CKD management.

Test-retest reliability and minimal detectable change scores for the short physical performance battery, one-legged standing test and timed up and go test in patients undergoing hemodialysis.

Functional tests are commonly used for chronic kidney disease (CKD) patients undergoing hemodialysis (HD). However, the relative and absolute reliability of such physical performance-outcome assessments must first be determined in specific patient cohorts. The aims of this study were to assess the relative and the absolute reliability of the Short Physical Performance Battery (SPPB), One-Legged Stance Test (OLST), and Timed Up and Go (TUG) test, as well as the minimal detectable change (MDC) scores for these tests in CKD patients receiving HD. Seventy-one end-stage CKD patients receiving HD therapy, aged between 21 and 90 years, participated in the study. The patients completed two testing sessions one to two weeks apart and performed by the same examiner, comprising the following tests: the SPPB (n = 65), OLST (n = 62), and TUG test (n = 66). High intraclass correlation coefficients (≥0.90) were found for all the tests, suggesting that their relative reliability is excellent. The MDC scores for the 90% confidence intervals were as follows: 1.7 points for the SPPB, 11.3 seconds for the OLST, and 2.9 seconds for the TUG test. The reliability of the SPPB, OLST, and TUG test for this sample were all considered to be acceptable. The MDC data generated by these tests can be used to monitor meaningful changes in the functional capacity of the daily living-related activity of CKD patients on HD.

Comparison of RIFLE, AKIN, and KDIGO classifications for assessing prognosis of patients on extracorporeal membrane oxygenation.

BACKGROUND/PURPOSE: Acute kidney injury (AKI) developing during extracorporeal membrane oxygenation (ECMO) is associated with very poor outcome. The Kidney Disease: Improving Global Outcomes (KDIGO) group published a new AKI definition in 2012. This study analyzed the outcomes of patients treated with ECMO and identified the relationship between the prognosis and the KDIGO classification. METHODS: This study examined total 312 patients initially, and finally reviewed the medical records of 167 patients on ECMO support at a tertiary care university hospital between March 2002 and November 2011. Demographic, clinical, and laboratory variables were retrospectively collected as survival predicators. RESULTS: The overall mortality rate was 55.7%. In the analysis of the areas under the receiver operating characteristic curves, the KDIGO classification showed relatively higher discriminatory power (0.840 ± 0.032) than the Risk of renal failure, Injury to the kidney, Failure of kidney function, Loss of kidney function, and End-stage renal failure (RIFLE) (0.826 ± 0.033) and Acute Kidney Injury Network (AKIN) (0.836 ± 0.032) criteria in predicting in-hospital mortality. Furthermore, multiple logistic regression analysis showed that KDIGO, hemoglobin, and Glasgow Coma Scale score on the first day of patients on ECMO were independent predictors for in-hospital mortality. Finally, cumulative survival rates at 6-month follow-up after hospital discharge differed significantly for KDIGO stage 3 versus KDIGO stage 0, 1, and 2 (p < 0.001); and KDIGO stage 2 versus KDIGO stage 0 (p < 0.05). CONCLUSION: For those patients with ECMO support, the KDIGO classification proved to be a more reproducible evaluation tool with excellent prognostic abilities than RIFLE or AKIN classification.

Strengthening Renal Registries and ESRD Research in Africa.

In Africa, the combination of noncommunicable diseases, infectious diseases, exposure to environmental toxins, and acute kidney injury related to trauma and childbirth are driving an epidemic of chronic kidney disease and end-stage renal disease (ESRD). Good registry data can inform the planning of renal services and can be used to argue for better resource allocation, audit the delivery and quality of care, and monitor the impact of interventions. Few African countries have established renal registries and most have failed owing to resource constraints. In this article we briefly review the burden of chronic kidney disease and ESRD in Africa, and then consider the research questions that could be addressed by renal registries. We describe examples of the impact of registry data and summarize the sparse primary literature on country-wide renal replacement therapy in African countries over the past 20 years. Finally, we highlight some initiatives and opportunities for strengthening research on ESRD and renal replacement therapy in Africa. These include the establishment of the African Renal Registry and the availability of new areas for research. We also discuss capacity building, collaboration, open-access publication, and the strengthening of local journals, all measures that may improve the quantity, visibility, and impact of African research outputs.

The ISKDC classification and a new semiquantitative classification for predicting outcomes of Henoch-Schönlein purpura nephritis.

BACKGROUND: Histological findings from primary kidney biopsies were correlated with patient outcomes in a national cohort of paediatric Henoch-Schönlein nephritis (HSN) patients. METHODS: Primary kidney biopsies from 53 HSN patients were re-evaluated using the ISKDC (International Study of Kidney Disease in Children) classification and a modified semiquantitative classification (SQC) that scores renal findings and also takes into account activity, chronicity and tubulointerstitial indices. The ISKDC and SQC classifications were evaluated comparatively in four outcome groups: no signs of renal disease (outcome A, n = 27), minor urinary abnormalities (outcome B, n = 18), active renal disease (outcome C, n = 3) and renal insufficiency, end-stage renal disease or succumbed due to HSN (outcome D, n = 5). For the receiver operating characteristic and logistic regression analyses, outcomes A and B were considered to be favourable and outcomes C and D to be unfavourable. The median follow-up time was 7.3 years. RESULTS: The patients with an unfavourable outcome (C and D), considered together due to low patient numbers, had significantly higher total biopsy SQC scores and activity indices than those who had a favourable one (groups A and B). The chronicity and tubulointerstitial indices differed significantly only between group C + D and group A. The difference in areas under the curve between the total biopsy SQC scores and ISKDC findings was 0.15 [p = 0.04, normal-based 95% confidence interval (CI) 0.007-0.29, bias-controlled 95% CI -0.004 to 0.28]. CONCLUSIONS: Our results suggest that the modified SQC is more sensitive than ISKDC classification for predicting the outcome in HSN cases.

Intradialytic aerobic cycling exercise alleviates inflammation and improves endothelial progenitor cell count and bone density in hemodialysis patients.

Inflammation, endothelial dysfunction, and mineral bone disease are critical factors contributing to morbidity and mortality in hemodialysis (HD) patients. Physical exercise alleviates inflammation and increases bone density. Here, we investigated the effects of intradialytic aerobic cycling exercise on HD patients. Forty end-stage renal disease patients undergoing HD were randomly assigned to either an exercise or control group. The patients in the exercise group performed a cycling program consisting of a 5-minute warm-up, 20 minutes of cycling at the desired workload, and a 5-minute cool down during 3 HD sessions per week for 3 months. Biochemical markers, inflammatory cytokines, nutritional status, the serum endothelial progenitor cell (EPC) count, bone mineral density, and functional capacity were analyzed. After 3 months of exercise, the patients in the exercise group showed significant improvements in serum albumin levels, the body mass index, inflammatory cytokine levels, and the number of cells positive for CD133, CD34, and kinase insert domain-conjugating receptor. Compared with the exercise group, the patients in the control group showed a loss of bone density at the femoral neck and no increases in EPCs. The patients in the exercise group also had a significantly greater 6-minute walk distance after completing the exercise program. Furthermore, the number of EPCs significantly correlated with the 6-minute walk distance both before and after the 3-month program. Intradialytic aerobic cycling exercise programs can effectively alleviate inflammation and improve nutrition, bone mineral density, and exercise tolerance in HD patients.

Renal Transplantation in Advanced Chronic Kidney Disease Patients.

Kidney transplantation is the best option for patients with end-stage kidney disease. It is associated with better quality of life, lower medical costs, less hospitalization, and improved survival compared with wait-listed patients who remain on dialysis. Timely referral for transplantation is essential to reap the maximal benefit and should begin in the advanced chronic kidney disease stage prior to starting dialysis. Shortage of donor organs remains the biggest challenge to transplantation. With the improved success of kidney transplantation, candidate acceptance criteria continue to broaden. This article provides an overview of the pretransplantation multidisciplinary evaluation process detailing the factors that determine transplant candidacy.

Creation of a Successful Transposed Antecubital Radiocephalic Arteriovenous Fistula in Patient with Known Ipsilateral Modified Radical Mastectomy, Postoperative Radiation, and Proximal Central Venous Occlusion.

Native arteriovenous fistula (AVF) placement in patients with ipsilateral mastectomy and radiation has been avoided because of concerns regarding central venous outflow obstruction. To our knowledge, only 3 such cases have been reported. We present a patient with bilateral mastectomies and right-sided radiation therapy presenting for vascular access in the setting of multiple failed AVF in her left upper extremity and infected-groin catheter, central catheters, and axillary loop graft. We created and superficialized a radiocephalic AVF in her right upper extremity in the setting of central vein occlusion and robust collaterals which remains patent and has been cannulated successfully.

Contrast induced acute kidney injury in acute coronary syndrome patients: A single centre experience.

BACKGROUND: The aim of the study was to investigate predictors of contrast induced acute kidney injury, in-hospital and long-term mortality in patients with acute coronary syndrome treated by percutaneous coronary intervention. METHODS: We investigated 536 consecutive patients with acute coronary syndrome who underwent percutaneous coronary intervention. Contrast induced acute kidney injury was classified according to risk, injury, failure, loss of kidney function and end-stage kidney disease/acute kidney injury network (RIFLE/AKIN) criteria into those with normal kidney function, risk, RIFLE stage I and those with stage ⩾ II. We investigated in-hospital, all-cause mortality during index hospitalization and long-term all-cause mortality during the follow-up period of 94 months (interquartile 81.6-108.9 months) in adjustment with parameters of the Global Risk of Acute Coronary Events score. RESULTS: Patients with contrast induced acute kidney injury had worse baseline clinical characteristics and displayed more co-morbidities than patients with normal kidney function. In multivariate logistic regression analysis intra-aortic balloon pump use, congestive heart failure, age >75 years and admission serum creatinine >1.5mg/dl were independent predictors of contrast induced acute kidney injury development. contrast induced acute kidney injury RIFLE stage ⩾ II was an independent predictor of in-hospital mortality (odds ratio 33.16, confidence interval 1.426-770.79, p=0.029) and long-term mortality (hazard ratio 4.713, confidence interval 1.53-14.51, p=0.007) even after adjustment for confounders (variables of Global Risk of Acute Coronary Events score). CONCLUSION: Contrast induced acute kidney injury is a common complication of acute coronary syndrome patients treated by percutaneous coronary intervention. Advanced deterioration in renal function after percutaneous coronary intervention is an independent predictor for in-hospital and long-term mortality.

KDIGO 2012 Clinical Practice Guideline CKD classification rules out creatinine clearance 24 hour urine collection?

OBJECTIVES: The recent guideline for the evaluation and management of Chronic Kidney Disease recommends assessing GFR employing equations based on serum creatinine; despite this, creatinine clearance 24-hour urine collection is used routinely in many settings. In this study we compared the classification assessed from CrCl (creatinine clearance 24h urine collection) and e-GFR calculated with CKD-EPI or MDRD formulas. DESIGN AND METHODS: In this retrospective study we analyze consecutive laboratory data: creatinine clearance 24h urine collection, serum creatinine and demographic data such as sex and age from 15,777 patients >18 years of age collected from 2011 to 2013 in our laboratory at Careggi Hospital. The results were then compared to the estimated GFR calculated with the equations according to the recent treatment guidelines. Consecutive and retrospective laboratory data (creatinine clearance 24h urine collection, serum creatinine and, demographic data such as sex and age) from 15,777 patients >18 years of age seen at Careggi Hospital were collected. RESULTS: Comparison between e-GFR calculated with CKD-EPI or MDRD formulas and GFR according CrCl determinations and bias [95% CI] were 11.34 [-47,4/70.1] and 11.4 [-50.2/73] respectively. The concordance for 18/65 years aged group when compared with e-GFR classification between MDRD vs CKDEPI, MDRD vs CrCl and CKD-EPI vs CrCl were 0.78, 0.34, and 0.41 respectively, while in the 65/110years aged group the concordance Kappas were 0.84, 0.38, and 0.36 respectively. CONCLUSIONS: The use of CrCl provides a different classification than the estimation of GFR using a prediction equation. The CrCl is unreliable when it is necessary to identify CKD subjects with decrease of GFR of 5ml/min/1.73m(2)/year.

Significance, definition, classification and risk factors of chronic kidney disease in South Africa.

Renal dysfunction or chronic kidney disease (CKD) is found in 10% of the global population and is classified into five stages according to the estimated glomerular filtration rate (eGFR). No matter where a patient lives, estimation of the GFR is mandatory for decision-making and obtained by the simple measurement of a serum creatinine level. The objective of diagnosing CKD lies in its future prevention, early detection and proper treatment, which will prevent or delay functional deterioration. Primary hypertension (PH) occurs in 25% of South Africa (SA)s black population and is the putative cause of stage 5 CKD in 40 - 60% of these patients. Moreover, in this group, stage 5 CKD occurs at a relatively young age (35 - 45 years) compared with other population groups in whom stage 5 CKD resulting from PH usually occurs between 60 and 70 years of age. In the cohort study, PH has been found in 12 - 16% of black school learners (mean age 17 years) compared with 1.8 - 2% of other ethnic groups (mixed race, Asian, white). End-stage renal failure (ESRF) is the fifth most common cause of death in SA, excluding post-traumatic cases. In addition, undiagnosed or poorly controlled PH is a potent risk factor for other cardiovascular disease (CVD), e.g. congestive cardiac failure, myocardial infarction, stroke. Significant protein is also associated with CVD and protein >1 g/d is a significant risk factor for ESRF.