Delayed post-dialysis recovery times are associated with relative changes in intracellular and extracellular fluid ratios between different body compartments.

INTRODUCTION: Hemodialysis patient groups have advocated reducing dialysis fatigue and symptoms. We investigated whether compartmental fluid shifts were associated with peri-dialytic fatigue and symptoms. METHODS: Sessional dialysis records of patients reporting both a short and delayed recovery (<1 h and ≥1 h) with corresponding bioimpedance measurements were reviewed. RESULTS: One hundred and twenty-four patients reported both short and delayed recovery times, mean age 66.0 ± 14.8 years, 66.1% male. Differences between sessions included higher distress thermometer [4 (1-6) vs. 3 (0-5)], fatigue [4 (0-9) vs. 2 (0-7)], total symptom scores [20.5 (12.3-34.5) vs. 16 (7-28)], change in extracellular water to total body water ratios between body compartments [right leg/left arm 2.36 (1.23-4.19) vs. 1.28 (0.12-2.01), all p < 0.01] with delayed recovery, and more hemodialysis than hemodiafiltration sessions (χ2 4.6, p = 0.02). CONCLUSION: Sessions with prolonged recovery times were associated with more peri-dialytic symptoms, psychological distress, and hemodialysis mode, and greater changes in compartmental fluid shifts.

Do patients dialysing with higher ultrafiltration rates report more intradialytic symptoms and longer postdialysis recovery times?

BACKGROUND: Many hemodialysis (HD) patients report intradialytic symptoms, and take time to recover postdialysis. To improve quality of life, patient groups have highlighted the need to reduce postdialysis fatigue and other peridialytic symptoms. As compartmental shifts of fluid during dialysis have been proposed to cause peridialytic symptoms we investigated whether patients dialysing with higher ultrafiltration rates (UFR) reported more intradialytic symptoms and recovery times. METHODS: We reviewed the hospital records of HD patients who completed a self-reported intradialytic symptom questionnaire, using a visual analogue scale, who had contemporaneous midweek pre- and postdialysis segmental bioimpedance measurements. RESULTS: Six hundred and five patients returned the peridialytic symptom questionnaire with pre- and postdialysis bioimpedance measurements. The majority were male (64.8%), mean age 64.2 ± 15.6 years, duration of dialysis treatment 26.8 (10.7-59.2) months, 85% treated by hemodiafiltration and mean dialysate temperature 35.4 ± 0.4°C. We divided patients into terciles according to UFR adjusted for weight, and there was a greater fall in the ratio of extracellular water (ECW) to total body water (TBW) postdialysis in the nonfistula arm from the lower to middle to higher tercile (0.8 (0-1.54) vs. 1.28 (0.52-1.85) vs. 1.54 (0.78-2.52)), trunk (1.5 (0.74-2.27) vs. 1.53 (0.99-2.2) vs. 1.98 (1.18-2.66)), left leg (1.56 (0.49-2.25) vs. 1.77 (1.24-2.43) vs. 2.08 (1.18-2.95)), lower versus higher tercile p < 0.05. However, no differences in intradialytic symptoms or postdialysis recovery times between the UFR terciles were observed. CONCLUSION: There were no differences in self-reported intradialytic symptoms or postdialysis recovery times with differing UFRs, despite changes in intracompartmental fluid shifts as measured by changes in ECW/TBW.

Efficacy of the Cytokine Adsorption Therapy in Patients with Severe COVID-19-Associated Pneumonia: Lesson Learned from a Prospective Observational Study.

INTRODUCTION: Severe COVID-19 pneumonia can activate a cytokine storm. Hemoperfusion can reduce pro-inflammatory cytokines in sepsis but is still debated in the COVID-19 setting. Thus, we sought to investigate the benefits of HA-330 cytokine adsorption through clinical and laboratory outcomes. METHODS: We conducted a single-center prospective observational study in adults with severe COVID-19 pneumonia admitted to the intensive care unit at Chiang Mai University Hospital (Chiang Mai, Thailand). Those with cytokine storms indicated by organ injury, including acute respiratory distress syndrome (ARDS), and high inflammatory markers were included. Patients treated with the HA-330 device were classified as a hemoperfusion group, while those without cytokine adsorption were classified as a control group. We compared the outcomes on day 7 after treatment and evaluated the factors associated with 60-day mortality. RESULTS: A total of 112 patients were enrolled. Thirty-eight patients received hemoperfusion, while 74 patients did not. Baseline cytokine storm parameters were comparable. In univariate analysis, there was an improvement in clinical and laboratory effects from hemoperfusion therapy. In multivariate analysis, APACHE II score, SOFA score, PaO2/FiO2, the number of hemoperfusion sessions, the amount of blood purified, high-sensitivity C-reactive protein, and IL-6 were associated with mortality. Using at least 3 sessions of hemoperfusion could mitigate, the 60-day mortality (adjusted odds ratio 0.25, 95% confidence interval: 0.03-0.33, p = 0.001). By categorizing the amount of blood treated into 3 groups of <1 L/kg, 1-2 L/kg, and ≥2 L/kg, there was a linear dose-response association with survival, which was better in the higher volume purified (mortality 60% vs. 33.3% vs. 0%, respectively, p = 0.015). CONCLUSIONS: The early initiation of HA-330 hemoperfusion could improve the severity score and laboratory outcomes of COVID-19 ARDS. The optimal dose of at least three sessions or the amount of blood purified greater than 1 L/kg was associated with a reduction in 60-day mortality.

Correction: Narongkiatikhun et al. Immunogenicity and Safety of Homologous and Heterologous Prime-Boost of CoronaVac® and ChAdOx1 nCoV-19 among Hemodialysis Patients: An Observational Prospective Cohort Study. Vaccines 2023, 11, 175.

The authors wish to make the following correction to this paper [...].

Immunogenicity and Safety of Homologous and Heterologous Prime-Boost of CoronaVac® and ChAdOx1 nCoV-19 among Hemodialysis Patients: An Observational Prospective Cohort Study.

BACKGROUND: Vaccines that prevent SARS-CoV-2 infection are considered the most promising approach to modulating the pandemic. There is scarce evidence on the efficacy and safety of different vaccine prime-boost combinations in MHD patients since most clinical trials have used homologous mRNA vaccine regimens. METHODS: This prospective observational study assessed the immunogenicity and safety of homologous CoronaVac® (SV-SV), ChAdOx1 nCoV-19 (AZD1222) (AZ-AZ), and the heterologous prime-boost of SV-AZ, among MHD patients. RESULTS: A total of 130 MHD participants were recruited. On day 28, after the second dose, seroconversion results of the surrogate virus neutralization test were not different between vaccine regimens. The magnitude of the receptor-binding domain-specific IgG was highest among the SV-AZ. Different vaccine regimens had a distinct impact on seroconversion, for which the heterologous vaccine regimen demonstrated a higher probability of seroconversion (OR 10.12; p = 0.020, and OR 1.81; p = 0.437 for SV-AZ vs. SV-SV, and SV-AZ vs. AZ-AZ, respectively). There were no serious adverse events reported in any of the vaccine groups. CONCLUSIONS: Immunization with SV-SV, AZ-AZ, and SV-AZ could generate humoral immunity without any serious adverse events among MHD patients. Using the heterologous vaccine prime-boost seemed to be more efficacious in terms of inducing immunogenicity.

Comparative effectiveness of lactulose and sennosides for the prevention of peritoneal dialysis-related peritonitis: an open-label, randomized, active-controlled trial.

BACKGROUND: To the best of our knowledge, the effectiveness and safety of lactulose in comparison to sennosides, for the prevention of peritoneal dialysis (PD)-related peritonitis, has never been tested in a randomized study. METHODS: We conducted an open-label, randomized, active-controlled trial in a PD-center in Northern Thailand. Adult patients on PD were enrolled and randomly assigned in a 1:1 ratio into two groups; one group received lactulose 15 mL once daily (n = 50) and the other group received sennosides two tablets daily (n = 50). The primary outcome was time-to-first bacterial peritonitis. The secondary outcomes included a composite of bacterial peritonitis and all-cause mortality. Cox proportional hazards regression was calculated and presented as hazard ratios (HRs) with 95% confidence intervals (CIs). RESULTS: One hundred PD patients were recruited (50.0% men; mean age 55.5 ± 13.0 years) in this study. The baseline characteristics of the study participants were similar in both groups. No significant trend towards a higher risk of PD-related peritonitis was observed in the lactulose group (HR, 2.32 [95% CI, 0.92-5.83]; p = .051) compared to the sennosides group. Nevertheless, the secondary outcome was significantly higher in the lactulose group (HR, 2.77 [95% CI, 1.20-6.41]; p = .010). The incidence of adverse events was not substantially different between the two groups; however, diarrhoea was more frequent in the lactulose group (38.0% vs. 18.0%; p = .030) than in the sennosides group. CONCLUSIONS: Treatment with lactulose is not more effective than sennosides and cannot be routinely recommended for the prevention of peritonitis among the PD population. TRIAL REGISTRATION Thai Clinical Trial Registry (clinicaltrials.in.th); ID: TCTR20171012001 KEY MESSAGE To the best of our knowledge, no randomized controlled trial that compares the efficacy and safety profiles of lactulose versus sennosides for the prevention of PD-related peritonitis among the PD population has been conducted. In this open-label, randomized, active-controlled trial, treatment with lactulose is not more effective than sennosides in the prevention of PD-related peritonitis, and it could increase the risk of bacterial PD-related peritonitis. Further studies with a larger sample size by incorporated real-world evidence are needed to confirm our findings and to explore strategies to prevent peritonitis among PD patients.

Hemodialysis patients with less extracellular water overload and smaller cardiac atrial chamber sizes are at greater risk of a fall in blood pressure during dialysis.

Intradialytic hypotension is the most common complication of hemodialysis (HD) treatments. Excessive ultrafiltration results in reduced cardiac preload. We aimed to determine whether a fall in systolic blood pressure during HD was greater in patients starting HD with (a) less overhydration measured by extracellular water (ECW) and (b) lower cardiac preload by cardiac magnetic resonance imaging (MRI). Pre-HD measurements of ECW and total body water (TBW) were performed using multifrequency bioimpedance (MFBIA). Cardiac chamber sizes and functions were determined by MRI. Twenty-six patients, 18 males (69.2%), 11 (42.3%) with diabetes, mean age 63.9 ± 15.9 years were studied. Systolic blood pressure (SBP) fell in 15 (57.7%) patients, and either did not change or increased in 9. There was no difference in demographics between groups. Patients with a fall in SBP had lower pre-HD ECW/TBW (0.400 ± 0.018 vs 0.418 ± 0.021), indexed right ventricular end-diastolic volume (81.2 ± 37.6 vs 100.8 ± 33.7 mL/m2 ), and indexed left atrial size (13.7 ± 3.9 vs 18.3 ± 5.0 mL/m2 ), all P < .05, respectively. There were univariate correlations between the change in SBP and pre-HD ECW/TBW for the trunk (r = .50, P = .009) and indexed left atrial volume (r = .54, P = .005). A fall in blood pressure occurred more commonly in patients starting HD with lower overhydration as measured by bioimpedance, and those with smaller cardiac chamber sizes. Patients with the lowest ECW/TBW and smallest cardiac chamber sizes had the greatest falls in SBP. This study reinforces the importance of determining physiological target weights and avoiding inappropriately low target weights for HD patients.

Comparison between standard single chamber versus dual chamber low glucose degradation product peritoneal dialysis fluids.

Dual chamber (DC) peritoneal dialysis (PD) dialysates contain fewer glucose degradation products (GDPs), so potentially reducing advanced glycosylation end products (AGEs), which have been reported to increase inflammation and cardiovascular risk. We wished to determine whether use of DC dialysates resulted in demonstrable patient benefits. Biochemical profiles, body composition, muscle strength, and skin autofluorescence measurements of tissue AGEs (SAF) were compared in patients using DC and standard single chamber dialysates. We studied 263 prevalent PD patients from 2 units, 62.4% male, mean age 61.8 ± 16.1 years, 78 (29.7%) used DC dialysates. DC patients were younger (55.9 ± 16.4 vs. 64.2 ± 15.4 years), and more had lower Davies comorbidity score (median 1 (0-1) vs. 1 (0, 2)), slower peritoneal transport (D/P creatinine 0.67 ± 0.12 vs. 0.73 ± 0.13), greater extracellular water-to-total body water (ECW/TBW) ratio (0.46 ± 0.05 vs. 0.42 ± 0.06), all P < .001, whereas there were no differences in the duration of PD (median (IQR) 19 (8-32) vs. 14 (8-23) months), residual renal function (Kt/Vurea 0.71 ± 0.71 vs. 0.87 ± 0.82), urine volume (642 (175-1200) vs. 648 (300-1200) mL/day), hand grip strength (26.9 ± 10.5 vs. 24.9 ± 10.7 kg), C-reactive protein (4(1-10) vs. 4(2-12) mg/L), and SAF (median 3.60 (3.02, 4.40) vs. 3.50 (3.00, 4.23)) AU. In our cross-sectional observational study, we were not able to show a demonstrable advantage for using low GDP dialysates over conventional glucose dialysates, in terms of biochemical profiles, residual renal function, muscle strength, or tissue AGE deposition. More patients using low GDP dialysates were slower peritoneal transporters with higher ECW/TBW ratios.

Plasma volume treated with double filtration plasmapheresis and outcomes of acute antibody-mediated rejection in kidney transplant recipients: A retrospective cohort study.

A retrospective cohort study was conducted to evaluate the association between the plasma volume treated by double filtration plasmapheresis and allograft outcomes for the treatment of acute antibody-mediated rejection in kidney transplant recipients. Patients were divided into two groups: group 1, plasma volume treated between 1 and <1.3 total plasma volume and group 2, plasma volume treated ≥1.3 total plasma volume. Primary outcome was ≥50% reduction of serum creatinine rising from baseline value at 1 month. A total of 32 courses (146 sessions) of double filtration plasmapheresis were performed; 17 and 15 courses in group 1 and group 2, respectively. Primary outcome occurred in 41% of group 1 and 40% of group 2 (adjusted risk ratio 1.15 [95%CI, 0.48-2.76]). Graft loss at 1 year did not differ between the two groups (adjusted hazard ratio 0.65 [95%CI, 0.23-1.87]). Infection tendency seemed to be higher in group 2 (40% vs 18%, P = .243).

The association between peri-dialytic pulse wave velocity measurements and hemodialysis patient mortality.

INTRODUCTION: Arterial stiffness in the general population is an independent prognostic factor for cardiovascular mortality, and can be measured noninvasively by pulse wave velocity (PWV). PWV is increased in hemodialysis (HD) patients, but the prognostic additional value remains debatable, with variable results reported. We wished to review whether increased PWV was associated with mortality in our HD patients. METHODS: Aortic pulse wave velocity (PWVao) was measured peridialytic using an oscillograph technique (Arteriograph TensioMed, Hungary), in a cohort of HD patients in 2012. FINDINGS: Three hundred and eighty-three HD patients, 238 (62.1%) male, median age 67.7 (54.2-78.0) years, 163 (42.6%) diabetic, Charlson comorbidity score 7 (5-9) and PWVao 8.9 (7.4-11.2) m/s were studied. Two hundred and twenty-nine deaths occurred during a median 61.1-month follow-up. PWVao was associated with all-cause mortality in unadjusted models (odds ratio [OR] for PWVao as a continuous variable 1.084, 95% confidence limits [CL] 1.046-1.124), P < 0.001, and for patients with PWVao>10 m/s (OR 1.61, CL 1.240-2.098, P < 0.001), but not after adjusting for clinical confounders (OR 1.024, CL 0.987-1.063, P = 0.208), whereas age (OR 1.049, CL 1.038-1.060, P < 0.001), and Charlson comorbidity (OR 1.131, CL1.065-1.201, P < 0.001) remained significantly associated with mortality. DISCUSSION: Although our HD patients with an increased PWVao had greater all-cause mortality, after adjustment for age and comorbidity, the prognostic value of a single PWVao measurement was no longer an independent prognostic factor for mortality. Future studies are required to determine whether changes in PWV offer additional prognostic value for HD patients.

Comparison of skin autofluorescence, a marker of tissue advanced glycation end-products in the fistula and non-fistula arms of patients treated by hemodialysis.

Advanced glycosylation end-products (AGEs) are reported to be a risk factor for cardiovascular mortality in hemodialysis (HD) patients. As serum AGEs can change with dialysis, measurement of AGEs deposited in the skin by autofluorescence (SAF) is now a recognized method of measuring AGEs. An arteriovenous fistula (AVF) is the preferred way to access blood in HD patients, and as the creation of an AVF changes blood flow distribution in the arm, we wished to determine whether this affected SAF deposition in the skin. SAF was measured using the AGE reader, which directs ultraviolet light at an intensity range of 300-420 nm (peak 370 nm) in the arms of HD patients dialyzing with an AVF. We measured SAF in 267 patients, 60.3% male, 46.1% diabetic, median duration of dialysis 34.7 (15.1-64.2) months with AVF. The median SAF was lower in the AVF arm (median 3.4 (2.9-4.2) vs. 3.7 (3.2-4.5) AU, P < .001), and for the 160 patients with an upper arm AVF (3.5 (2.9-4.3) vs. 3.8 (3.2-4.5) AU, P < .001), but not for the 107 patients dialyzing with a forearm AVF ((3.4 (2.8-4.2) vs. 3.6 (3.0-4.5) AU, P = .085). Blood flow was greater for upper arm AVF compared to forearm AVFs (1190 (770-1960) vs. (930 (653-1250) mL/min, P = .007), but there was no association between blood flow and SAF (P > .05). AVF alters blood flow in the arm, and we found that SAF measurements were lower in the arm with AVF. We suggest that SAF measurements are made in the non-AVF arm.

Effects of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers on all-cause mortality, cardiovascular death, and cardiovascular events among peritoneal dialysis patients: A protocol for systematic review.

BACKGROUND: Based on the International Society for peritoneal dialysis (PD) recommendations, blockade of renin-angiotensin systems with an angiotensin-converting enzyme inhibitors (ACEI) and angiotensin receptor blockers (ARB) improves residual kidney function in PD patients. However, the long-term effectiveness of ACEI/ARB use in PD patients has not been fully elucidated. We, therefore, intend to perform a systematic review and meta-analysis to summarize the effects of ACEI/ARB use on long-term mortality, cardiovascular outcomes, and adverse events among PD patients. METHODS: This systematic review will include both randomized controlled trials and non-randomized studies in adult PD patients. We also plan to incorporate data from our cohort study in Thai PD population into this review. We will search PubMed, Medline, EMBASE, Cochrane Library, Web of Science, Scopus, CINAHL, and grey literature from inception to February 29, 2019, with no language restrictions. The process of study screening, selection, data extraction, risk of bias assessment, and grading the strength of evidence will be performed independently by a pair of reviewers. Any discrepancy will be resolved through a team discussion and/or consultation with the third reviewer. The pooled effects estimate and 95% confidence intervals will be estimated using DerSimonian-Laird random-effects models. Heterogeneity will be assessed by the Cochran Q test, I index and tau-squared statistics. The funnel plots along with the Begg and Egger test and trim and fill method will be performed to investigate any evidence of publication bias. Preplanned subgroup analyses and random-effects univariate meta-regressions will be performed to quantify the potential sources of heterogeneity based on studies- and patient-characteristics. RESULTS: This will be the first systematic review and meta-analysis to summarize the long-term effectiveness of renin-angiotensin system inhibitors in PD populations. CONCLUSION: In summary, this systematic review and meta-analysis will summarize the effectiveness of ACEI/ARB on long-term mortality, cardiovascular outcomes, and adverse events among adult PD patients by integrated all available evidences. ETHICS AND DISSEMINATION: Based on the existing published data, an ethical approval is not required. The findings will be disseminated through scientific meetings and publications in peer-reviewed journals.PROSPERO registration number: CRD42019129492.

Efficacy of Furosemide, Oral Sodium Chloride, and Fluid Restriction for Treatment of Syndrome of Inappropriate Antidiuresis (SIAD): An Open-label Randomized Controlled Study (The EFFUSE-FLUID Trial).

RATIONALE & OBJECTIVE: First-line therapy for syndrome of inappropriate antidiuresis (SIAD) is fluid restriction. Additional treatment for patients who do not respond to fluid restriction are water restriction with furosemide or water restriction with furosemide and salt supplementation. However, the efficacy of these treatments has never been tested in a randomized controlled study. The objective of this study was to investigate whether, combined with fluid restriction, furosemide with or without sodium chloride (NaCl) supplementation was more effective than fluid restriction alone in the treatment of hyponatremia in SIAD. STUDY DESIGN: Open-label randomized controlled study. SETTING & PARTICIPANTS: Patients with serum sodium concentrations ([Na+]) ≤ 130mmol/L due to SIAD. INTERVENTION(S): Random assignment to 1 of 3 groups: fluid restriction alone (FR), fluid restriction and furosemide (FR+FM), or fluid restriction, furosemide, and NaCl (FR+FM+NaCl). Strictness of fluid restriction (<1,000 or<500mL/d) was guided by the urine to serum electrolyte ratio. Furosemide dosage was 20 to 40mg/d. NaCl supplements were 3g/d. All treatments were continued for 28 days. OUTCOMES: The primary outcome was change in [Na+] at days 4, 7, 14, and 28 after randomization. RESULTS: 92 patients were recruited (FR, n=31; FR+FM, n=30; FR+FM+NaCl, n=31). Baseline [Na+] was 125±4mmol/L, and there were no significant differences between groups. Mean [Na+] on day 4 in all treatment groups was significantly increased from baseline by 5mmol/L (P<0.001); however, the change in [Na+] was not significantly different across groups (P=0.7). There was no significant difference in percentage of patients or time to reach [Na+] ≥ 130 or≥135mmol/L across the 3 groups. Acute kidney injury and hypokalemia (potassium≤3.0mmol/L) were more common in patients receiving furosemide. LIMITATIONS: Open-label treatment. CONCLUSIONS: In patients with SIAD, furosemide with NaCl supplement in combination with fluid restriction did not show benefits in correction of [Na+] compared with treatment with fluid restriction alone. Incidences of acute kidney injury and hypokalemia were increased in patients receiving furosemide. FUNDING: None. TRIAL REGISTRATION: Registered at the Thai Clinical Trial Registry with study number TCTR20170629004.

Factors associated with systolic hypertension in peritoneal dialysis patients.

BACKGROUND: Hypertension is common in peritoneal dialysis (PD) patients and associated with adverse outcomes. Besides solute clearance, PD convective clearance is used to control extracellular water (ECW) volume and sodium balance. Previous studies have reported on hypertension in PD patients treated with continuous ambulatory peritoneal dialysis (CAPD) using hypertonic glucose dialysates. However, increasing numbers of PD patients are now treated with automated peritoneal dialysis (APD) and icodextrin dialysates. As such, we wished to explore factors associated with systolic blood pressure (SBP) in a modern cohort to identify targets to improve blood pressure control in PD patients. METHODS: We retrospectively reviewed the results from PD patients attending for peritoneal membrane assessment who had corresponding bioimpedance ECW and brain natriuretic peptide (NT-proBNP) measurements. RESULTS: We studied 510 PD patients: 317 (72.2%) male, 216 (42.4%) diabetics, median age 59 (47-72) years, and 51% treated by APD with a day-time icodextrin exchange. Mean systolic blood pressure (SBP) was 140 ± 24.8 mmHg. SBP was independently associated with 4-hour dialysate to plasma creatinine ratio (ß = 29.5 (95% confidence limits 11.4-47.5, p = 0.001), N-terminal brain natriuretic peptide [ß = 11.9 (7.2-16.7), p < 0.001], and daily urine sodium excretion [ß = 1.7 (1.0-2.3), p < 0.001]. CONCLUSION: In the era of APD cyclers and icodextrin, SBP is associated with increased NT-proBNP, a marker of ECW expansion, and faster peritoneal transport, a risk factor for a positive sodium balance, and increased urinary sodium suggestive of higher dietary sodium intake. Patients should be encouraged to restrict sodium intake and PD prescriptions targeted to control ECW to improve SBP control.

The effect of gender on survival for hemodialysis patients: Why don't women live longer than men?

Women in the general population have a survival advantage over men, but this advantage is not sustained in end-stage kidney disease (ESKD) patients treated by hemodialysis. To understand why gender may affect survival we need to understand confounders which may affect dialysis practices. The current paradigm is to prescribe hemodialysis to achieve a target dialyzer urea clearance adjusted to total body water volume (Kt/Vurea ). Estimated glomerular filtration calculated from serum creatinine is often used to determine when patients start dialysis; as creatinine generation rates are lower in women, this may potentially result in a lead time bias with male patients starting dialysis earlier than females. When hemodialysis dose is scaled to total body water (Kt/Vurea ) women receive shorter dialysis session times. Scaling dialysis for body surface area may be more appropriate since urea generation (a surrogate for uremic toxin production) depends upon resting energy expenditure (ie, cellular metabolism) which reflects internal organ sizes. Resting energy expenditure is proportionally greater for smaller people. Women are generally smaller than men and as such have smaller sized internal organs. However, when comparing individuals, then internal organ size is best adjusted for using body surface area, not body water. The shorter, resultant dialysis session also results in lower middle molecule clearances, increases fluid removal rates and the risk of intra-dialytic hypotension; the latter potentially results in earlier loss of residual renal function. Observational studies report that the association between survival and dialyzer Kt/Vurea is improved after adjustment for body surface area, or energy expenditure. These studies also demonstrated that the conventional prescription of hemodialysis based on current Kt/Vurea targets leads to less treatment delivered to women. These multiple consequences of the generally smaller size of women compared with men may account for the unexpectedly higher relative mortality for women. As such, prospective studies investigating alternative scaling parameters are required to confirm that increasing dialysis treatments for women improves survival.

Differences between Measured Total Nitrogen Losses in Spent Peritoneal Dialysate Effluent and Estimated Nitrogen Losses.

OBJECTIVE: Patients treated by peritoneal dialysis (PD) are at increased risk of muscle wasting, and clinical guidelines recommend assessing dietary intake, by calculating protein equivalent of nitrogen appearance (PNA) to assure protein sufficiency. The PNA equations were developed many years ago, and we wished to re-evaluate them by comparing estimated and measured peritoneal nitrogen losses. DESIGN AND METHODS: This is a cross-sectional observational cohort study. The study setting was an outpatient PD center of a university hospital and the study subjects included 67 patients undergoing PD, in which 61.2% were males, and the median age was 67.3 (53.2-79.4) years. The nitrogen content of 24-hour spent peritoneal dialysate by automated chemiluminescence analyzer was measured and compared with estimates of nitrogen losses based on dialysate urea loss using the Bergstrom, Randerson, and Blumenkrantz equations. RESULTS: Measured total dialysate nitrogen was more than urea nitrogen equivalent, 5.79 ± 4.07 versus 2.66 ± 1.67 g/day (P < .001). Each equation has an inflation factor to compensate for nonurea protein losses; however, measured nitrogen loss was 27.7 (15.5-59.6) g/day versus Bergstrom, 16.5 (9.8-27.1); Randerson, 16.4 (9.8-27.3); and Blumenkrantz, 12.9 (7.9-25.4) g/day, P < .001. The BlandAltman analysis demonstrated systematic bias with increasing underestimation by these equations with increasing measured nitrogen losses (r = 0.74, P < .001). CONCLUSION: Our findings demonstrate that at higher protein losses, the currently used predictive equations underestimate the amount lost. It is important to attempt to compensate the iatrogenic protein loss by recommending the appropriate intake of dietary protein to patients, in an attempt to minimize muscle wasting. This discrepancy may have arisen because of the characteristics of newer PD prescriptions and change in patient demographics. We propose a new equation PNA g/day = 0.31 × (urea loss mmol) + 7.17, which will require prospective validation in additional studies.

Comparison of skin autofluorescence, a marker of tissue advanced glycation end-products in peritoneal dialysis patients using standard and biocompatible glucose containing peritoneal dialysates.

BACKGROUND: Heat sterilization of peritoneal dialysis (PD) dialysates leads to the generation of advanced glycation products (AGE), which can then deposit in the skin and be measured by skin autofluorescence (SAF). Newer biocompatible dual chamber dialysates contain less AGE. We wished to determine whether the use of these newer dialysates resulted in lower SAF. METHODS: Skin autofluorescence was measured using the AGE reader, which directs ultraviolet light, intensity range 300-420 nm (peak 370 nm) in patients established on PD for >3 months using glucose containing dialysates. RESULTS: We screened 196 consecutive patients, and measured SAF in 150; 86 (57.3%) male, median age 62 (53-71) years, median duration of PD treatment 17 (8.6-34.3) months. The median SAF was 3.48 (2.92-4.26) AU. The median SAF in the 57 (38%) patients prescribed biocompatible dual chamber bag dialysates was 3.39 (2.69-3.98) versus 3.5 (3.05-4.54) for those using standard dialysates (P = 0.044). Although prescription of biocompatible fluids was associated with SAF on univariate analysis, but not on multivariable testing, SAF was independently associated with Stoke-Davies co-morbidity grade (ß 0.045, 95% confidence limits (CL) 0.015-0.075, P = 0.002), log duration of PD therapy (ß 0.051, CL 0.001-0.101, P = 0.045), white ethnicity (ß 0.066, CL 0.028-0.104, P = 0.001), and negatively with serum albumin (ß -0.006, CL -0.008 to -0.004, P = 0.014). CONCLUSION: Although SAF was lower in PD patients prescribed biocompatible dual chamber dialysates, on multivariable testing these dialysates were not independently associated with SAF. Other factors than PD fluid AGE content appear more important in determining SAF.

Estimating Dietary Protein Intake in Peritoneal Dialysis Patients: The Effect of Ethnicity.

Kidney dialysis patients with sarcopenia have increased mortality. Clinical guidelines recommend peritoneal dialysis (PD) patients have a target daily protein intake to prevent sarcopenia. Protein intake is estimated from total daily urea losses in urine and peritoneal dialysate to assess the protein equivalent of nitrogen appearance rate adjusted for body weight (nPNA). Dietary habits differ among ethnic groups, so we reviewed nPNA and body composition in a multi-ethnic PD population. Body composition was measured with multifrequency bioimpedance in 598 patients (301 white, 136 black, 123 South-Asian, and 38 Asian-Pacific). South-Asians had a lower nPNA compared with white and black individuals (Randerson 0.80 ± 0.21 vs 0.88 ± 0.24 and 0.85 ± 0.24 g/kg/day, Blumenkrantz 0.97 ± 0.14 vs 1.04 ± 0.22 and 0.99 ± 0.22 g/kg/day, Bergström 0.87 ± 0.4 vs 0.95 ± 0.24 and 0.92 ± 0.24 g/kg/day all p < 0.001). South-Asians had lower weights (68.9 ± 14.9 vs 74.4 ± 16.6 and 73.5 ± 16.3 kg, p < 0.001), and although of similar body mass index (25.9 ± 4.9 vs 28.5 ± 4.9 and 26.5 ± 5.2 kg/m2), had both lower skeletal muscle and appendicular muscle mass indexed for height (9.08 ± 1.45 vs 9.89 ± 1.62 and 10.1 ± 1.85, p < 0.001; and 6.95 ± 1.39 vs 7.68 ± 1.48 and 7.67 ± 1.58 kg/m2p < 0.01). South-Asian patients had a lower calculated basal metabolic rate (BMR) (1,358 ± 218 vs 1,487 ± 257 and 1,489 ± 271 kcal/day, p < 0.001).Asian PD patients, particularly South-Asians, have lower dietary protein intakes when calculated by nPNA. However, South-Asians had lower measured muscle mass and calculated BMR. As such, dietary protein intake targets derived from studies in 1 ethnic group are not necessarily applicable for all patients, as those with less muscle mass and lower BMR may well need less daily protein intake to maintain homeostasis.

Differences in the prevalence of sarcopenia in peritoneal dialysis patients using hand grip strength and appendicular lean mass: depends upon guideline definitions.

BACKGROUND: Peritoneal dialysis (PD) patients with sarcopenia have increased risk of mortality. There is consensus that sarcopenia should combine assessments of muscle function and mass. We wished to determine the effect of using different operational definitions in PD patients. METHODS: Hand grip strength (HGS) and segmental bioimpedance derived appendicular lean mass (ALM) were measured and the prevalence of sarcopenia determined using the Foundation for the National Institutes of Health Sarcopenia Project (FNIH), European Working Group on Sarcopenia Older Persons (EWGSOP), and Asian Working Group on Sarcopenia (AWGS) definitions. RESULTS: We studied 155 PD patients, 95 men (61.3%), mean age 63.0 ± 14.9 years, 37.4% diabetic, treated by PD 9 (3-20) months with a HGS of 22.5 (15.5-30.2) kg, weight 73.6 ± 16.6 kg, % body fat 31.4 ± 4.2, and ALM index 7.52 ± 1.40 kg/m2. More patients were defined with muscle weakness using the EWGSOP compared to the FNIH criteria (X2 = 6.8, p = 0.009), whereas fewer patients met the EWGSOP criteria for muscle wasting compared to FNIH body mass index adjustment (X2 = 7.7, p = 0.006). However, when combining both criteria, there was no difference in the prevalence of sarcopenia between the different recommended definitions (11-15.5%). CONCLUSION: We report a much lower prevalence of sarcopenia compared to studies in haemodialysis patients. Although there may be an element of patient selection bias, PD patients are not subject to changes in hydration and electrolytes with haemodialysis, which can affect HGS and muscle mass measurements. Using HGS and segmental bioimpedance we found similar prevalence of sarcopenia using EWGSOP, FNIH, AWGS definitions.

Cryptococcal meningitis in HIV-infected patients at Chiang Mai University Hospital: a retrospective study.

Cryptococcal meningitis (CM) is a common central nervous system infection in HIV-infected patients. This study aimed to determine treatment outcomes among HIV-infected patients who had cryptococcal meningitis and to determine predictors of death. We conducted a retrospective cohort study among HIV-infected patients receiving care at Chiang Mai University Hospital from January 1, 2005 to December 31, 2010. We studied 79 patients; 45 (57.0%) were male and the mean age was 35.1 +/- 7.2 years. Eleven patients (13.9%) had previous opportunistic infection. The most common presenting symptoms were headache (63 patients, 79.8%), fever (49 patients, 62.0%), and altered consciousness (21 patients, 26.6%). The median CD4+ cell count was 20 cells/mm3 [Interquartile range (IQR) 10, 53]. The in-hospital, 90-day, and 1-year mortality rates were 24.1%, 32.4%, and 52.2%, respectively. The CM attributable in-hospital, 90-day and 1-year mortality rates were 13.9%, 20.3%, and 23.2%, respectively. Predictors associated with a 1-year mortality were a high cerebrospinal (CSF) cryptococcal antigen titer (> 1:10,000) [Odds Ratio (OR) =7.08, 95% confidence interval (CI): 1.62-31.00, p = 0.009], and altered consciousness at presentation (OR = 5.27; 95% CI: 1.16-24.05; p = 0.032). Cryptococcal meningitis is an important cause of death in HIV-infected patients. HIV-infected patients with a low CD4+ cell count, a headache, fever and altered consciousness should be investigated for CM and those with a high CSF cryptococcal antigen titer are at high risk for mortality.