Plasma Exchange and Glucocorticoids in Severe ANCA-Associated Vasculitis.

BACKGROUND: More effective and safer treatments are needed for antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis. METHODS: We conducted a randomized trial with a 2-by-2 factorial design to evaluate the use of plasma exchange and two regimens of oral glucocorticoids in patients with severe ANCA-associated vasculitis (defined by an estimated glomerular filtration rate of <50 ml per minute per 1.73 m2 of body-surface area or diffuse pulmonary hemorrhage). Patients were randomly assigned to undergo plasma exchange (seven plasma exchanges within 14 days after randomization) or no plasma exchange (control group). Patients were also randomly assigned to follow either a standard-dose regimen or a reduced-dose regimen of oral glucocorticoids. Patients were followed for up to 7 years for the primary composite outcome of death from any cause or end-stage kidney disease (ESKD). RESULTS: Death from any cause or ESKD occurred in 100 of 352 patients (28.4%) in the plasma-exchange group and in 109 of 352 patients (31.0%) in the control group (hazard ratio, 0.86; 95% confidence interval [CI], 0.65 to 1.13; P = 0.27). The results were similar in subgroup analyses and in analyses of secondary outcomes. We also assessed the noninferiority of a reduced-dose regimen of glucocorticoids to a standard-dose regimen, using a noninferiority margin of 11 percentage points. Death from any cause or ESKD occurred in 92 of 330 patients (27.9%) in the reduced-dose group and in 83 of 325 patients (25.5%) in the standard-dose group (absolute risk difference, 2.3 percentage points; 90% CI, -3.4 to 8.0), which met the criterion for noninferiority. Serious infections at 1 year were less common in the reduced-dose group than in the standard-dose group (incidence rate ratio, 0.69; 95% CI, 0.52 to 0.93), but other secondary outcomes were similar in the two groups. CONCLUSIONS: Among patients with severe ANCA-associated vasculitis, the use of plasma exchange did not reduce the incidence of death or ESKD. A reduced-dose regimen of glucocorticoids was noninferior to a standard-dose regimen with respect to death or ESKD. (Funded by the U.K. National Institute for Health Research and others; PEXIVAS Current Controlled Trials number, ISRCTN07757494; ClinicalTrials.gov number, NCT00987389.).

Hydration for health hypothesis: a narrative review of supporting evidence.

PURPOSE: An increasing body of evidence suggests that excreting a generous volume of diluted urine is associated with short- and long-term beneficial health effects, especially for kidney and metabolic function. However, water intake and hydration remain under-investigated and optimal hydration is poorly and inconsistently defined. This review tests the hypothesis that optimal chronic water intake positively impacts various aspects of health and proposes an evidence-based definition of optimal hydration. METHODS: Search strategy included PubMed and Google Scholar using relevant keywords for each health outcome, complemented by manual search of article reference lists and the expertise of relevant practitioners for each area studied. RESULTS: The available literature suggest the effects of increased water intake on health may be direct, due to increased urine flow or urine dilution, or indirect, mediated by a reduction in osmotically -stimulated vasopressin (AVP). Urine flow affects the formation of kidney stones and recurrence of urinary tract infection, while increased circulating AVP is implicated in metabolic disease, chronic kidney disease, and autosomal dominant polycystic kidney disease. CONCLUSION: In order to ensure optimal hydration, it is proposed that optimal total water intake should approach 2.5 to 3.5 L day-1 to allow for the daily excretion of 2 to 3 L of dilute (< 500 mOsm kg-1) urine. Simple urinary markers of hydration such as urine color or void frequency may be used to monitor and adjust intake.

Hydration Status and Kidney Health of Factory Workers Exposed to Heat Stress: A Pilot Feasibility Study.

Dehydration associated with heat stress increases the risk of workplace injury or illness, decreases productivity, and may contribute to the chronic kidney disease epidemic identified in outdoor workers from hot climates. There is limited research on the effects of chronic occupational heat stress among indoor workers. We aimed to test the feasibility of measuring markers of hydration and kidney function in foundry factory workers in Southern Brazil, exposed and not exposed to heat stress. Factory workers exposed to heat stress (wet bulb globe temperature ≥28.9) and not exposed to heat were identified by management and invited to participate. Clinical and biochemical markers of hydration and kidney function were evaluated before and after a single 8.5 h work shift (lunch time not included). Feasibility outcomes included rates of enrolment, % completion of study protocols, and time to complete data collection. This study was deemed feasible with 80% enrolment and 90% completion of the protocol. Among the preselected workers, the enrolment rate was 91%. All subjects completed the physiological measures and blood collection and 95% completed the urine studies. Mean time to complete data collection pre-shift was 19.1 ± 4.2 min and post-shift: 14.3 ± 4.0 min. Workers exposed to heat stress had a greater decline in estimated glomerular filtration rate compared to controls over the work shift (-13 ± 11 vs. -5 ± 7 mL/min; p < 0.01). We demonstrated the feasibility and challenges of conducting future hydration and kidney function research among indoor factory workers. Further study is needed to determine if exposure to indoor heat contributes to a decline in kidney function.

Effect of Coaching to Increase Water Intake on Kidney Function Decline in Adults With Chronic Kidney Disease: The CKD WIT Randomized Clinical Trial.

Importance: In observational studies, increased water intake is associated with better kidney function. Objective: To determine the effect of coaching to increase water intake on kidney function in adults with chronic kidney disease. Design, Setting, and Participants: The CKD WIT (Chronic Kidney Disease Water Intake Trial) randomized clinical trial was conducted in 9 centers in Ontario, Canada, from 2013 until 2017 (last day of follow-up, May 25, 2017). Patients had stage 3 chronic kidney disease (estimated glomerular filtration rate [eGFR] 30-60 mL/min/1.73 m2 and microalbuminuria or macroalbuminuria) and a 24-hour urine volume of less than 3.0 L. Interventions: Patients in the hydration group (n = 316) were coached to drink more water, and those in the control group (n = 315) were coached to maintain usual intake. Main Outcomes and Measures: The primary outcome was change in kidney function (eGFR from baseline to 12 months). Secondary outcomes included 1-year change in plasma copeptin concentration, creatinine clearance, 24-hour urine albumin, and patient-reported overall quality of health (0 [worst possible] to 10 [best possible]). Results: Of 631 randomized patients (mean age, 65.0 years; men, 63.4%; mean eGFR, 43 mL/min/1.73 m2; median urine albumin, 123 mg/d), 12 died (hydration group [n = 5]; control group [n = 7]). Among 590 survivors with 1-year follow-up measurements (95% of 619), the mean change in 24-hour urine volume was 0.6 L per day higher in the hydration group (95% CI, 0.5 to 0.7; P < .001). The mean change in eGFR was -2.2 mL/min/1.73 m2 in the hydration group and -1.9 mL/min/1.73 m2 in the control group (adjusted between-group difference, -0.3 mL/min/1.73 m2 [95% CI, -1.8 to 1.2; P = .74]). The mean between-group differences (hydration vs control) in secondary outcomes were as follows: plasma copeptin, -2.2 pmol/L (95% CI, -3.9 to -0.5; P = .01); creatinine clearance, 3.6 mL/min/1.73 m2 (95% CI, 0.8 to 6.4; P = .01); urine albumin, 7 mg per day (95% CI, -4 to 51; P = .11); and quality of health, 0.2 points (95% CI, -0.3 to 0.3; P = .22). Conclusions and Relevance: Among adults with chronic kidney disease, coaching to increase water intake compared with coaching to maintain the same water intake did not significantly slow the decline in kidney function after 1 year. However, the study may have been underpowered to detect a clinically important difference. Trial Registration: clinicaltrials.gov Identifier: NCT01766687.

How we treat thrombotic thrombocytopenic purpura: Results of a Canadian TTP practice survey.

BACKGROUND: Thrombotic thrombocytopenic purpura (TTP) is a rare disease with 90% mortality if untreated. Since the Canadian Apheresis Group (CAG) trial showed greater survival with therapeutic plasma exchange (TPE) versus plasma infusion, there has been widespread adoption of TPE. Beyond TPE, there is significant practice variation. To characterize this, we developed a survey sent to physicians who might be directly involved in TTP management. METHODS: The survey was sent to CAG members as well as hematologists and nephrologists nationwide and addressed areas of controversy or recognized practice heterogeneity. Descriptive statistics were used to summarize responses, and the χ2 test was used to compare respondents who were and were not CAG physicians. We also compared responses by estimated frequency of TTP cases per year. RESULTS: The CAG response rate was 31% (13 of 42). The survey was sent to 665 non-CAG physicians, of whom 41 responded (6.1%). Though not statistically different, CAG and non-CAG respondents varied regarding use of corticosteroids, aspirin, and venous thromboembolism (VTE) prophylaxis. Significant differences were found between CAG and non-CAG groups regarding cryosupernatant as fluid choice (69.2% vs. 22.5%, P = .004) and the use of TPE tapering (84.6% vs. 51.3%, P = .034), respectively. CONCLUSION: TTP treatment is variable across centres in Canada. Areas of significant variation include the choice of replacement fluid for TPE and whether or not and how to taper TPE. Our survey highlights the practice heterogeneity that exists and identifies areas where more evidence is needed and perhaps where trials should be performed.

Plasmapheresis for the treatment of kidney diseases.

The purpose of this review is to examine the evidence supporting the application of plasma exchange in renal disease. Our review focuses on the following 6 most common renal indications for plasma exchange based on 2014 registry data from the Canadian Apheresis Group: (i) thrombotic thrombocytopenic purpura (TTP)/hemolytic uremic syndrome; (ii) renal transplantation, (iii) anti-neutrophil cytoplasm antibodies-associated vasculitis, (iv) cryoglobulinemia, (v) focal segmental glomerulosclerosis, and (vi) Goodpasture syndrome. The rarity of these diseases and their rapid, often fatal course mean that randomized controlled studies of plasma exchange are rarely conducted. Although evidence from an adequately powered randomized controlled trial supports the use of plasma exchange to treat thrombotic thrombocytopenic purpura, the use of plasma exchange to treat other renal diseases is only supported by observational and mechanistic studies. Larger well-designed trials are needed to clarify the potential role of plasma exchange in renal disease. Growing international collaboration will improve the quality of future studies in this area.

Hydration and Chronic Kidney Disease Progression: A Critical Review of the Evidence.

We performed a comprehensive literature review to examine evidence on the effects of hydration on the kidney. By reducing vasopressin secretion, increasing water intake may have a beneficial effect on renal function in patients with all forms of chronic kidney disease (CKD) and in those at risk of CKD. This potential benefit may be greater when the kidney is still able to concentrate urine (high fluid intake is contraindicated in dialysis-dependent patients). Increasing water intake is a well-accepted method for preventing renal calculi, and current evidence suggests that recurrent dehydration and heat stress from extreme occupational conditions is the most probable cause of an ongoing CKD epidemic in Mesoamerica. In polycystic kidney disease (PKD), increased water intake has been shown to slow renal cyst growth in animals via direct vasopressin suppression, and pharmacologic blockade of renal vasopressin-V2 receptors has been shown to slow cyst growth in patients. However, larger clinical trials are needed to determine if supplemental water can safely slow the loss of kidney function in PKD patients.

Long-term outcomes of thrombotic microangiopathy treated with plasma exchange: A systematic review.

With the adoption of plasma exchange as standard treatment for thrombotic microangiopathy (TMA), more patients are surviving and long-term outcomes have greater relevance. We conducted a systematic review to synthesize and evaluate the quality of evidence on long-term outcomes of TMA among adults treated with plasma exchange and to identify factors that may be associated with a worse long-term prognosis. We searched databases from 1980 to 2013 for eligible articles published in any language. We included studies that reported outcomes in at least ten adults with a history of TMA treated with plasma exchange and at least 6 months of follow-up. We abstracted data in duplicate and assessed the methodological quality of each study using an assessment tool developed based on recommended validity criteria. We screened 6672 articles, reviewed 213, and included 34 studies totaling 1182 patients (study median [range], 24 [10-118]). The mean (or median) follow-up ranged from 6 months to 13 years. The cumulative incidence of relapse and mortality was highly variable and ranged from 3 to 84 and 0 to 61%, respectively. The incidence of other outcomes across 10 studies also varied (outcomes included hypertension, kidney disease, preeclampsia, stroke, seizure, severe cognitive impairment, and depression); in three other studies, long-term neurocognitive function and health-related quality of life were significantly lower than in the general population. Patients who survive an episode of TMA may be susceptible to long-term vascular complications, but the magnitude of this risk and how to mitigate it remains unclear. Am. J. Hematol. 91:623-630, 2016. © 2016 Wiley Periodicals, Inc.

International Society of Nephrology-Hydration and Kidney Health Initiative - Expanding Research and Knowledge.

The purpose of this manuscript is to describe a collaborative research initiative to explore the role of hydration in kidney health. Our understanding of the effects of hydration in health and disease is surprisingly limited, particularly when we consider the vital role of hydration in basic human physiology. Recent initiatives and research outcomes have challenged the global medical community to expand our knowledge about hydration, including the differences between water, sugared beverages and other consumables. Identification of the potential mechanisms contributing to the benefits of hydration has stimulated the global nephrology community to advance research regarding hydration for kidney health. Hydration and kidney health has been a focus of research for several research centers with a rapidly expanding world literature and knowledge. The International Society of Nephrology has collaborated with Danone Nutricia Research to promote development of kidney research initiatives, which focus on the role of hydration in kidney health and the global translation of this new information. This initiative supports the use of existing data in different regions and countries to expand dialogue among experts in the field of hydration and health, and to increase scientific interaction and productivity with the ultimate goal of improving kidney health.

The role of plasma exchange in treating post-transplant focal segmental glomerulosclerosis: A systematic review and meta-analysis of 77 case-reports and case-series.

BACKGROUND: Evidence on the role of plasma exchange for treating recurrent post-transplant focal segmental glomerulosclerosis (FSGS) comes largely from individual cases and uncontrolled series. We conducted a systematic review and meta-analysis to estimate the remission rate after treatment with plasma exchange, and to determine if remission varied with patient or treatment characteristics. METHODS: We searched MEDLINE, EMBASE, Science Citation Index Expanded, and the Conference Proceedings Citation Index (Science and BIOSIS) for studies of patients with post-transplant recurrent FSGS who were treated with plasma exchange after recurrence (1950-2012). Of 678 studies screened, 77 met our inclusion criteria: 34 case reports (45 patients) and 43 case series (378 patients). We extracted patient-level data from each study and used random-effects models to calculate remission, defined as proteinuria <3.5 g/day (partial) or <0.5 g/day (complete). RESULTS: The overall remission rate in 423 patients with outcome data was 71 % (95 % CI: 66 % to 75 %). In 235 patients with data on age, remission was similar for adults and children: 69.1 % (95 % CI: 59.6 % to 77.2 %) and 70.2 % (95 % CI: 61.1 % to 77.9 %). Males were more likely to achieve remission (OR = 2.85; 95 % CI: 1.44 to 5.62) and patients treated within 2 weeks of recurrence showed a trend towards higher likelihood of remission (OR = 2.16; 95 % CI: 0.93 to 5.01). Proteinuria >7 g/day at recurrence was inversely associated with remission (OR = 0.43; 95 % CI: 0.19 to 0.97). Age and type of kidney transplant (living vs. deceased) did not associate with remission. CONCLUSION: In this systematic review of patients with recurrent post-transplant FSGS, 71 % of patients achieved full or partial remission after treatment with plasma exchange; however, extensive missing data and lack of a control group limit any conclusions on causality.

Characteristics and Outcomes of AKI Treated with Dialysis during Pregnancy and the Postpartum Period.

Acute kidney injury (AKI) is a rare complication of pregnancy, but may be associated with significant morbidity and mortality in young and often otherwise healthy women. We conducted a retrospective population-based cohort study of all consecutive pregnancies over a 15-year period (1997-2011) in Ontario, Canada, and describe the incidence and outcomes of AKI treated with dialysis during pregnancy or within 12 weeks of delivery. Of 1,918,789 pregnancies, 188 were complicated by AKI treated with dialysis (incidence: 1 per 10,000 [95% confidence interval, 0.8 to 1.1]). Only 21 of 188 (11.2%) women had record of a preexisting medical condition; however, 130 (69.2%) women experienced a major pregnancy-related complication, including preeclampsia, thrombotic microangiopathy, heart failure, sepsis, or postpartum hemorrhage. Eight women died (4.3% versus 0.01% in the general population), and seven (3.9%) women remained dialysis dependent 4 months after delivery. Low birth weight (<2500 g), small for gestational age, or preterm birth (<37 weeks' gestation) were more common in pregnancies in which dialysis was initiated (35.6% versus 14.0%; relative risk, 3.40; 95% confidence interval, 2.52 to 4.58). There were no stillbirths and fewer than five neonatal deaths (<2.7%) in affected pregnancies compared with 0.1% and 0.8%, respectively, in the general population. In conclusion, AKI treated with dialysis during pregnancy is rare and typically occurs in healthy women who acquire a major pregnancy-related medical condition such as preeclampsia. Many affected women and their babies have good short-term outcomes.

A phase-II sequential case-series study of all patients presenting to four plasma exchange centres with presumed relapsed/refractory thrombotic thrombocytopenic purpura treated with rituximab.

The primary objective of this phase II study was to evaluate the efficacy of rituximab in the management of adult patients with physician-diagnosed presumed thrombotic thrombocytopenic purpura (TTP); relapsed or refractory. We conducted a multicentre study in four Canadian hospital-based apheresis units. Forty patients with presumed TTP (20 refractory and 20 relapsing) were sequentially enrolled and all received rituximab in a standardized manner. A complete response was documented in 14 of 19 refractory patients by week 8 and 15/16 were alive and in remission at 52 weeks (one patient was lost to follow-up, one was a non-responder, and three died). Among relapsing patients, 16/18 had a complete response at week 8 and 18/18 at week 52 (one patient lost to follow-up and one withdrew). At 1 year, all relapsing and 85% of refractory patients survived. Of 38/40 patients who had ADMATS13 testing at study entry, 13/19 refractory and 10/19 relapsing patients had ADAMTS13 < 10% (typical TTP); whereas 6/19 refractory and 9/19 relapsing cases had ADAMTS13 > 10% (other thrombotic microangiopathy; TMA). Refractory-typical TTP in contrast to refractory-other TMA and all relapsing patients treated with plasma exchange and rituximab, were less likely to be responsive and more likely to die or relapse.

Primary and Secondary Thrombotic Microangiopathy Referred to a Single Plasma Exchange Center for Suspected Thrombotic Thrombocytopenic Purpura: 2000-2011.

BACKGROUND: Patients who present with unexplained thrombocytopenia, that is, hemolytic anemia with end-organ dysfunction with a normal coagulation profile are suspected to have thrombotic thrombocytopenic purpura (TTP) and are usually referred to a plasma exchange (PE) center for immediate treatment to prevent mortality. Here, we describe the distribution and outcomes of patients with suspected TTP referred to a single center for PE therapy. METHODS: In this retrospective cohort study, we reviewed the data of all consecutive patients who were treated with PE for suspected TTP at our center between January 2000 and December 2011 (Canada). Patients were followed for a median of 73 months. RESULTS: Of 137 patients, 70 (51%) were determined to have primary (idiopathic) TTP and 67 (49%) secondary TTP or hemolytic uremic syndrome (HUS). Patients with primary TTP were twice as likely to be refractory than those with secondary TTP or HUS: 27 vs. 12%; p = 0.03. Patients with primary TTP were more likely to experience remission (61/70 (87%) vs. 45/67 (67%); p = 0.01); however, the relapse rate was higher in patients with primary versus secondary TTP-HUS: 11 vs. 1.5%, respectively (p = 0.03). The overall mortality rate was 23% (13 vs. 33% in those with primary vs. secondary TTP-HUS; p = 0.007). After excluding deaths from scleroderma renal crisis (100% mortality), malignancy (75% mortality) and stem cell transplant (50% mortality), the survival rate for secondary TTP was 85%. CONCLUSIONS: In contrast to patients with secondary TTP or HUS, those with primary TTP have a higher refractory and relapse rate, but are also more likely to achieve remission and survive.

Increasing Water Intake in Chronic Kidney Disease: Why? Safe? Possible?

Increased water intake may slow the progression of chronic kidney disease by lowering vasopressin levels. Prior to initiating a large randomized controlled trial on the effect of increased water intake on renal decline, we conducted a six-week pilot study to examine the safety and feasibility of asking adults with chronic kidney disease to increase their water intake. We randomly assigned 29 patients to either a hydration or a control group. The hydration group was asked to increase water intake by 1 to 1.5 l/day relative to their weight, gender, and 24 h urine osmolality, in addition to usual consumed beverages; the control group was asked to continue with usual fluid intake. After six weeks, the change in urine volume was significantly different between groups (0.9 l/day; p = 0.002) with no change in serum sodium and no serious adverse effects. Similarly, preliminary results of our large clinical trial of the same intervention (489 patients enrolled to date) demonstrated a significant separation between groups on 24 h urine volume (at 12 months the mean difference between groups was 1.2 l/day; p < 0.001) with no serious adverse effects. Serum sodium has remained stable in both groups over follow-up. To our knowledge, this trial is currently the largest of its kind to date; the significant separation between groups with respect to urine volume indicates that we will have scientifically reliable data on the effect of increased fluid intake on renal decline. The analysis of primary and secondary outcomes will be conducted at the conclusion of follow-up in July 2016.

Hyponatremia and sodium picosulfate bowel preparations in older adults.

OBJECTIVES: Bowel preparations are commonly prescribed drugs. Case reports and our clinical experience suggest that sodium picosulfate bowel preparations can precipitate severe hyponatremia in some older adults. At present, this risk is poorly quantified. We investigated the association between sodium picosulfate use and the risk of hyponatremia in older adults. METHODS: We conducted a population-based retrospective cohort study using six linked administrative databases in Ontario, Canada. All Ontario residents over the age of 65 years who filled an outpatient bowel preparation prescription before colonoscopy were eligible. We enrolled new users of either sodium picosulfate (n=99,237) or polyethylene glycol (n=48,595). The primary outcome was hospitalization with hyponatremia within 30 days of the bowel preparation assessed by database codes. The secondary outcomes were hospitalization with urgent head computed tomography (CT) (a proxy for acute central nervous system disturbance) and all-cause mortality. RESULTS: The baseline characteristics of the two groups, including patient demographics, comorbid conditions, and concomitant medications, were nearly identical. Compared with polyethylene glycol, sodium picosulfate was associated with a higher risk of hospitalization with hyponatremia (absolute risk increase: 0.05%, 95% confidence interval (CI): 0.04-0.06%, relative risk (RR): 2.4, 95% CI: 1.5-3.9), but not hospitalization with urgent CT head (RR: 1.1, 95% CI: 0.7-1.4) or mortality (RR: 0.9, 95% CI: 0.7-1.3). CONCLUSIONS: Sodium picosulfate bowel preparations lead to more hyponatremia than polyethylene glycol. There was no evidence of increased risk of acute neurologic symptoms or mortality. The absolute increase in risk of hospitalization with hyponatremia remains low but may be avoidable through appropriate fluid intake or preferential use of polyethylene glycol in some older adults.

Timing of peritoneal dialysis initiation and mortality: analysis of the Canadian Organ Replacement Registry.

BACKGROUND: Several observational studies of hemodialysis patients show an association between early dialysis therapy initiation and increased mortality. Few studies have examined this association among peritoneal dialysis patients. STUDY DESIGN: Retrospective cohort study. SETTING & PARTICIPANTS: A cohort of 8,047 incident peritoneal dialysis patients who started dialysis therapy in 2001-2009 and were treated in Canada. PREDICTOR: Estimated glomerular filtration rate (eGFR) at dialysis therapy initiation. Defined early, mid, and late starts as eGFR>10.5, 7.5-10.5, and <7.5mL/min/1.73m(2), respectively. OUTCOMES: Time to death. MEASUREMENTS: Proportional piecewise exponential survival models to compare mortality (overall and early) for the 3 predictor groups. RESULTS: Between 2001 and 2009, the proportion of patients starting peritoneal dialysis therapy as early starts increased from 29% (95% CI, 26%-32%) to 44% (95% CI, 41%-47%). Compared with the late-start group, the overall mortality rate was not higher for the early- (adjusted HR, 1.08; 95% CI, 0.96-1.23) or mid-start (adjusted HR, 0.96; 95% CI, 0.86-1.09) groups. However, when examined yearly, patients in the early-start group were significantly more likely to die within the first year of dialysis therapy compared with those in the late-start group (adjusted HR, 1.38; 95% CI, 1.10-1.73), but not in subsequent years. LIMITATIONS: Bias and residual confounding may have influenced the observed relationship between predictor and outcome. CONCLUSIONS: Patients are initiating peritoneal dialysis therapy at increasingly higher eGFRs. Contrary to most observational studies assessing hemodialysis, the early initiation of peritoneal dialysis therapy, at eGFR>10.5mL/min/1.73m(2), is not associated with increased mortality.

Tandem hemodialysis and plasma exchange.

The combination of hemodialysis and plasma exchange as one tandem procedure was first described in 1999 by Siami et al. (ASAIO J 45:229-233), but larger pediatric case series were not described until 2012. Even in adults, there are only limited case series. If performed in sequence, up to 8 h of treatment time may be required. With the use of the tandem procedure in stable patients, the same procedures can be completed during the same time as a routine hemodialysis, which is more convenient for patients and may reduce healthcare costs. Little is known about the utilization of the combination of hemodialysis and plasma exchange in children. The purpose of this review is to summarize the adult and scarce pediatric experience. The results of a survey carried out by the authors using the Internet listserver "PedNeph" to obtain an overview of the current practice patterns of pediatric nephrologists are also presented.

Patients' quality of life after stopping plasma exchange: a pilot study.

BACKGROUND: Plasma exchange is being widely used to treat various serious medical conditions. There has been very little follow-up data to describe the quality of life (QOL) of plasma exchange-recipients after active plasma exchange has stopped. OBJECTIVE: To assess the QOL of plasma exchange recipients after stopping plasma exchange. METHODS: A pilot study, based on responses to a postal questionnaire and clinical data obtained from the patients' charts, was carried out. The scores were computed from questionnaire responses and analyzed. RESULTS: The response rate was 59% with 58 patients completing a questionnaire three months after their final plasma exchange therapy. We identified significant heterogeneity in the quality of life of plasma exchange recipients after stopping plasma exchange therapy. This could be driven by different patient co-morbidities. We recommend that during follow up visits, a multi-disciplinary approach including consultation with a social worker might be considered for patients who may continue to have some limitations in their psychosocial activities post-discontinuation of plasma exchange. The high response rate to the questionnaire indicates that PLEX patients are interested in being involved in QOL studies, which suggests potential support for a prospective study of QOL with pre and post questionnaires and more detailed tracking of baseline co-morbidities.

Has the yearly increase in the renal replacement therapy population ended?

The recent decline in the number of new patients undergoing dialysis and transplantation in the United States may be linked to a reduction in the incidence of early-start dialysis, defined as the initiation of renal replacement therapy (RRT) at an estimated GFR ≥10 ml/min per 1.73 m(2). We examined the most recent data from the U.S. Renal Data System to determine how this trend will affect the future incidence of ESRD in the United States. The percentage of early dialysis starts grew from 19% to 54% of all new starts between 1996 and 2009 but remained stable between 2009 and 2011. Similarly, the incident RRT population increased substantially in all age groups between 1996 and 2005, with the largest increase occurring in patients aged ≥75 years. Early dialysis starts accounted for most of the increase in the incident RRT population in all age groups during this time period, and between 2005 and 2010, the increase slowed dramatically. Although the future incident RRT population will be determined in part by population growth, these results suggest that later dialysis starts and greater use of conservative and palliative care, which may improve quality of life for elderly patients with advanced renal failure, will continue to attenuate the increase observed in previous years.

Association between water intake, chronic kidney disease, and cardiovascular disease: a cross-sectional analysis of NHANES data.

BACKGROUND: Evidence from animal and human studies suggests a protective effect of higher water intake on kidney function and cardiovascular disease (CVD). Here the associations between water intake, chronic kidney disease (CKD) and CVD were examined in the general population. METHODS: We conducted a cross-sectional analysis of the 2005-2006 National Health and Nutrition Examination Survey. Non-pregnant adults with an estimated glomerular filtration rate (eGFR) ≥30 ml/min/1.73 m(2) who were not taking diuretics were included. Total water intake from foods and beverages was categorized as low (<2.0 l/day), moderate (2.0-4.3 l/day) and high (>4.3 l/day). We examined associations between low total water intake and CKD (eGFR 30-60 ml/min/1.73 m(2)) and self-reported CVD. RESULTS: Of 3,427 adults (mean age 46 (range 20-84); mean eGFR 95 ml/min/1.73 m(2) (range 30-161)), 13% had CKD and 18% had CVD. CKD was higher among those with the lowest (<2.0 l/day) vs. highest total water intake (>4.3 l/day) (adjusted odds ratio (OR) 2.52; 95% confidence interval (CI) 0.91-6.96). When stratified by intake of (1) plain water and (2) other beverages, CKD was associated with low intake of plain water: adjusted OR 2.36 (95% CI 1.10-5.06), but not other beverages: adjusted OR 0.87 (95% CI 0.30-2.50). There was no association between low water intake and CVD (adjusted OR 0.76; 95% CI 0.37-1.59). CONCLUSIONS: Our results provide additional evidence suggesting a potentially protective effect of higher total water intake, particularly plain water, on the kidney.