Interferon-λ3 as a Predictor of Survival in Hemodialysis Patients.

BACKGROUND: IFNL4 polymorphisms are associated with circulating IFN-λ3, and higher plasma IFN-λ3 are associated with higher production of antibodies to HBV surface antigen (anti-HBs). The IFNL4 rs8099917 T allele and anti-HBs development in response to HBV vaccine are associated with better survival in hemodialysis (HD) patients. OBJECTIVE: To show whether plasma IFN-λ3 is also a predictor of survival in HD patients. METHODS: Plasma IFN-λ3 was measured in 135 HD patients who were followed-up for 2.6 years. Survival probability was tested using the Kaplan-Meier method and the Cox proportional hazard model. RESULTS: Plasma IFN-λ3 (ng/L) was 116.8 (20.4-227.5) in survivors on HD (n=89, 65.9%), 75.1 (36.0-228.8) in deceased patients (n=37, 27.4%), and 109.0 (40.0-232.7) in subjects submitted to kidney transplantation (n=9, 6.7%). IFN-λ3 was lower in deceased patients than that in all remaining patients (P=0.039) and patients who continued HD without transplantation (P=0.028). IFN-λ3 and anti-HBs titers were correlated (r=0.587, P<0.000001). Patients showing IFN-λ3 >126.1 ng/L (3rd tertile) presented better survival compared with patients with IFN-λ3 in the 1st (<73.8 ng/L, P=0.005) and 2nd (≥73.8 - <126.1 ng/L, P=0.013) tertiles. Each decrease in IFN-λ3 per 10 ng/L was associated with a hazard ratio equal to 1.076 (95%CI 1.015-1.140, P=0.013). In multivariate analysis, the independent predictors of survival were age (P=0.008), dialysis modality (P=0.038), circulating IFN-λ3 (P=0.044), and diabetic nephropathy (P=0.047), but not gender, dialysis duration prior to the study, mean arterial pressure, BMI, CRP, albumin, 25(OH)D, or anti-HBs. CONCLUSION: Circulating IFN-λ3 is a promising predictor of HD patient survival.

The role of nutritional status in the outcome of peritoneal dialysis patients.

Abnormalities in nutritional status of peritoneal dialysis (PD) patients include too high body mass (overweight, obesity), too low body mass (underweight, starvation) or changes in body composition (malnutrition) without or with normal body weight. In vivo neutron activation analysis is considered the reference gold standard for the determination of protein malnourishment in end-stage renal disease patients, but body mass index (BMI) is the most frequently used parameter in nutritional assessment surveys. The association between BMI and outcome of PD patients is controversial, but so-called obesity paradox (the higher BMI the longer survival) remains frequently reported. The use of metabolic syndrome with high BMI as a crucial component is not more predictable in the prognosis of outcome in PD patients than using separately each risk factor of metabolic syndrome. Underweight/starvation is univocally underlined as associated with morbidity and mortality, but prevalence of severe undernutrition is decreasing over last decades, at least in well developed countries. PD patients may also present features of malnutrition without decreased body mass or even with increased body weight. It mainly concerns to deficiencies of vitamins, minerals and trace elements. Serum albumin concentration has serious limitations as a marker of nutritional status, because is influenced by volemic status and inflammation. Nutritional interventions in undernourished patients (oral, intestinal or intravenous feeding, amino acid peritoneal solution, supplementation of vitamins and trace elements) may correct deficiencies, but their influence on PD patients survival remains unclear.

Bone pain in dialysis patients is not associated with bone mineral density but with serum concentration of small uremic toxins.

PURPOSE: Abnormalities in bone mineral density (BMD) are frequent disorder in dialysis patients. In our study we checked if such clinical symptom as bone pain may be associated with BMD. PATIENTS AND METHODS: The study was performed in 30 dialysis patients. They were divided according to declared or not declared bone pain in any localization. The group with bone pain (n=10) included 7 women and 3 men, age 57.4 +/- 16.2 years, dialysis vintage 19.3, 6.5-45.5 months. The group without bone pain (n=20) consisted of 11 women and 9 men, age 55.5 +/- 18.9 years, dialysis vintage 20.5, 6.3-59.6 months. BMD was assessed by dual-energy x-ray absorptiometry in femoral neck (N) and lumbar spine from the second to the fourth lumbar vertebra (L2-L4). Routine clinical and laboratory parameters were evaluated and compared in both groups. RESULTS: The group with bone pain had higher serum concentrations of phosphate (6.2 +/- 1.4 mg/dl vs 4.9 +/- 1.1 mg/dl, p = 0.012) and urea (136.0 +/- 37.4 mg/dl vs 111.3 +/- 23.5 mg/dl, p = 0.035) than the group without bone pain. After adjustment of results to gender, age and dialysis vintage these differences remained significant, additionally the group with bone pain had higher serum creatinine concentration than the group without bone pain (9.5 +/- 2.4 mg/dl vs 7.5 +/- 2.9 mg/dl, p = 0.009). There were no statistically significant differences between groups in BMD measured in N and L2-L4. CONCLUSION: Our results suggest that bone pain in dialysis patients is associated rather with serum concentration of small uremic toxins than with BMD.

Protecting the peritoneal membrane in dialyzed patients.

This review paper describes methods of protecting the peritoneal membrane in uremic patients chronically treated with peritoneal dialysis. Possible interventions involved in protection of the peritoneum aim at reducing peritoneal exposure to glucose, glucose degradation products and lactate; preventing or diminishing harmful effects of dialysis solutions; decreasing infection rate, especially peritonitis, and its consequences. Techniques reducing peritoneal exposure to bioincompatible solutions include peritoneal resting, replacing some glucose exchanges with amino acid-based, icodextrin-based or glycerol-based dialysis solution, using bicarbonate or pyruvate as a buffer, and administering solutions with low content of glucose degradation products. Preventing or diminishing harmful effects of dialysis solutions includes interventions with drugs, especially those given intraperitoneally. Decreasing local and systemic infection rate is also very or even the most important in maintaining relatively unchanged peritoneal membrane histology and function.

Results of improvement in adequacy of intermittent hemodialysis in uremic patients.

PURPOSE: Increasing number of patients, who need intermittent hemodialysis (IHD), is a great challenge for every society. The aim of study is to look if small increase in IHD adequacy is able to improve standard medical parameters. MATERIAL AND METHODS: In 40 patients, Kt/V was monitored on-line during the middle IHD session in the week, 4 times in each of 6 consecutive months. In the first month of observation Kt/V was lower (1.09 +/- 0.02) than in the further months, in which Kt/V was increasing to 1.17 +/- 0.01. Blood count was estimated every month. At the beginning of study period, after 3 months and at the end of studies, dry body mass, body mass index (BMI), the blood pH and serum concentration of calcium, phosphate, intact parathormone (iPTH), total protein, albumin, cholesterol, iron, ferritin, urea and creatinine were determined. RESULTS: The increase in Kt/V was accompanied by rising values of hemoglobin (Hb), hematocrit (Hct), mean corpuscular volume, iron, blood pH before and after IHD session as well as by decreasing values of PTH. Statistically unchanged parameters included dry body mass, BMI, serum concentration of total protein, phosphate, cholesterol and ferritin as well as white blood cells and platelet count. There were correlations between Kt/V and serum concentrations of phosphate, PTH, ferritin, Hb and Hct, indicating that higher IHD doses were provided to patients in more advanced uremic state. CONCLUSIONS: Even small increase in IHD adequacy leads to beneficial changes in management of uremic patients.

What is new in peritoneal dialysis in the years 2003-2004.

This review paper describes new data on the role of aquaporins in peritoneal function, peritoneal membrane permeability, peritoneal dialysis (PD) adequacy and peritoneal membrane histology, new aspects of the use of PD solutions alternative to glucose ones and indications for use of peritoneal catheters with different configurations. Results of main studies, published predominantly in 2003-2004, are presented and discussed. Clinically important news, although preliminary in some cases, are also included.

Ratio of cyclase activating and cyclase inactive parathormone (CAP/CIP) in dialysis patients: correlations with other markers of bone disease.

PURPOSE: We checked correlation of CAP/CIP with osteoprotegrin (OPG), its soluble ligand (OPGL) and routinely measured parameters of bone turnover in patients treated with peritoneal dialysis (PD) and hemodialysis (HD). MATERIAL & METHODS: In 30 patients (22 HD, 8 PD) we determined serum concentrations of intact parathormone (iPTH), CAP, OPG, OPGL, total Ca, inorganic phosphates (Pi), creatinine, urea, total alkaline phosphatase (AP) and blood pH. CIP was calculated by subtraction of CAP from iPTH. Controls (Cs) included 9 healthy persons in whom iPTH, CAP, OPG and OPGL were measured as well as CIP, CAP/CIP and OPGL/OPG were calculated. RESULTS: Differences between HD and PD patients included dialysis duration, OPGL, OPGL/OPG, AP, Pi, Ca and pH. After adjustment to dialysis duration differences in OPGL/OPG, Pi, Ca and pH remained significant. HD patients differed from Cs in terms of iPTH, CAP, CIP, OPGL, OPG and OPGL/OPG. In whole group of patients iPTH, CAP, CIP but not CAP/CIP correlated negatively with OPGL and OPGL/OPG as well as positively with dialysis duration, OPG and AP. CONCLUSIONS: Despite more advanced uremic bone disease in longer dialyzed HD patients than in shorter dialyzed PD ones, CAP/CIP is not different neither between these groups nor Cs persons. CAP/CIP does not seem to be more powerful tool in noninvasive diagnosis of bone disease than iPTH or CAP and CIP alone.

Serum osteoprotegerin level is lower in peritoneal dialysis patients than in hemodialysis ones.

PURPOSE: Osteoprotegrin (OPG) and OPG-ligand are involved in bone turnover induced by parathyroid hormone (PTH) in renal osteodystrophy. We determined serum OPG level in dialysis patients and checked its correlations with other parameters of bone turnover. MATERIAL AND METHODS: Serum level of OPG, PTH, phosphates (Pi), calcium, total alkaline phosphatase (AP) and pH was determined in 29 peritoneal dialysis (PD) patients and 41 hemodialysis (HD) ones. RESULTS: OPG level was lower in PD than HD patients (4.0, 2.1-13.4 pmol/L vs 7.9, 0.9-16.5 pmol/L; p = 0.000) and in both groups it was higher than in controls (2.2, 1.0-3.9 pmol/L; p = 0.000). PD patients had also lower AP (78.0, 34.0-583.0 U/L vs 116.0, 59.0-577.0 U/L; p = 0.000) and Pi (1.4 +/- 0.4 mmol/L vs 3.4 +/- 2.6 mmol/L; p = 0.000) than HD patients, but higher calcium level (2.4 +/- 0.2 mmol/L vs 2.2 +/- 0.3 mmol/L; p = 0.002) and pH (7.412 +/- 0.051 vs 7.326 +/- 0.043; p = 0.000). The only correlation displayed in PD patients for OPG was negative one with pH (r = -0.417, p = 0.038) and in HD patients--positive with Pi (r = 0.548, p = 0.000). OPG level was elevated in 38 HD (92.7%) and in 15 PD (51.7%) patients. There was correlation between serum OPG and AP (r = -0.615, p = 0.033) and calcium (r = 0.575, p = 0.040) in group characterised by normal OPG value. There were no significant correlations in group with elevated OPG level. CONCLUSIONS: Lower serum OPG level in PD patients may be connected with lower activity of osteoclasts and less compensating production of OPG in this group of patients. Lower serum OPG level may contribute to higher serum calcium level in PD patients.

Lymphocyte subsets in the course of continuous ambulatory peritoneal dialysis.

The present study evaluated whether estimation of lymphocyte subset counts can be more helpful than total lymphocyte count (TLC) in earlier diagnosis of immune and nutritional changes in the course of continuous ambulatory peritoneal dialysis (CAPD). For the study, 50 CAPD patients were divided into four groups depending on dialysis duration. Group I consisted of patients treated for 6-12 months (n = 15); group II, for 13-24 months (n = 16); group III, for 25-36 months (n = 12); and group IV, for more than 36 months (n = 7). Thirteen patients, being 8 +/- 7 days before CAPD initiation, were included in group 0. Flow cytometry was used for estimation of lymphocyte subsets (determination of CD3, CD4, CD8, CD19, and CD16 + 56 antigens). Our uremic patients started CAPD therapy with decreased TLC and lymphocyte subset (excluding CD16 + 56) counts. After 6-12 months of CAPD therapy, a significant increase in TLC, CD4:CD8 ratio, and all examined lymphocyte subset counts was observed. In the next years of CAPD therapy, TLC, CD3, CD4, CD8, and CD19 cell counts decreased. In patients on CAPD for more than 36 months, CD3, CD4, CD8, and CD19 cell counts were below the normal range, but mean TLC was maintained in the normal range, and CD16 + 56 exceeded the upper limit of normal. A significant negative correlation between CD19 cell count and dialysis duration was seen (r = -0.298, p = 0.035, n = 50). In conclusion, the first months of CAPD therapy see an improvement in immune and nutritional status as expressed by an increase in TLC, lymphocyte subset counts, and CD4:CD8 ratio. Repeat determinations of CD3, CD4, CD8, and CD19 cell counts indicate that these counts decrease earlier than an evaluation of TLC indicates. We recommend lymphocyte subset determinations for detection of immune and nutritional abnormalities in the course of CAPD treatment. An increase in natural killer cells above the normal range may reflect chronic sterile or infectious inflammatory response, which deteriorates nutritional status.

Polyglucose dialysis solution induces changes in blood chemistry.

In peritoneal dialysis patients, polyglucose dialysis solution (PG-DS) influences serum levels of sodium, amylase, and lipase, and of iron parameters. We aimed to examine, in the blood or serum of continuous ambulatory peritoneal dialysis (CAPD) patients treated with PG-DS, changes in the concentrations of Na+, K+, Ca++, total Ca, phosphorus, urea nitrogen, creatinine, uric acid, total protein, albumin, and intact parathyroid hormone (iPTH); in lipid profile [total cholesterol, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, triglycerides, HDL:total cholesterol ratio]; and in acid-base status. We started studies in 14 CAPD patients in whom 7.5% PG-DS was applied for the overnight 2-L exchange (duration: about 10 hours). Determinations of blood chemistry were carried out at 1.6 +/- 0.8 months before the introduction of PG-DS (period I, n = 14); after 1.2 +/- 0.6 months (period II, n = 14), 4.4 +/- 0.8 months (period III, n = 11), and 8.8 +/- 2.4 months (period IV, n = 9) of PG-DS administration; and 2.0 +/- 0.6 months after PG-DS discontinuation (period V, n = 11). The most pronounced (significant) differences in the examined parameters were seen between periods I and III or periods I and IV for Na+ (140 +/- 3 mmol/L vs 136 +/- 4 mmol/L), K+ (4.2 +/- 0.6 mmol/L vs 4.8 +/- 0.6 mmol/L), total Ca (9.4 +/- 1.1 mg/dL vs 10.5 +/- 1.3 mg/dL), urea nitrogen (61.3 +/- 25.9 mg/dL vs 79.4 +/- 20.9 mg/dL), creatinine (10.7 +/- 2.6 mg/dL vs 12.8 +/- 4.3 mg/dL), uric acid (4.8 +/- 2.3 mg/dL vs 7.1 +/- 1.7 mg/dL), and total protein (61.7 +/- 10.8 g/L vs 70.5 +/- 8.0 g/L). Serum lipid levels were stable during PG-DS administration, but they increased after discontinuation of the PG-DS. Other studied parameters usually returned to pre-treatment values after PG-DS discontinuation. All patients were in good clinical status during the study. The changes in blood chemistry did not cause clinical intervention. Our results indicate that PG-DS influences blood chemistry. The observed differences need to be clinically analyzed.

Bone mass in chronic renal insufficiency patients treated with continuous ambulatory peritoneal dialysis.

Chronic renal failure (CRF) causes deterioration of the fluid, electrolyte, and acid-base balances, azotemia, and impairment of the structure and function of many systems. In the skeletal system, CRF changes both the quality and quantity of the bone through its multifactorial influence on bone metabolism, leading to osteopenia, osteoporosis, and increased risk of fracture. The aim of the present study was to work up the quickest and most sensitive schedule for detecting osteoporosis in chronic renal insufficiency patients treated with CAPD. Thirty-seven uremic patients were included in the study. Bone mineral density was measured by dual-energy x-ray absorptiometry in lumbar spine, femoral neck, forearm (33% distal and ultradistal sites), and total body. Analyzing all five sites, we made the assessment that the prevalence of osteoporosis in our group of patients reached 48.6%. If only one site was evaluated, the ultradistal part of forearm yielded the highest frequency of diagnosis of osteoporosis (37.8%). Next came the femoral neck and total body (21.6% each). When the two sites in the forearm were taken into account together, the incidence of osteoporosis reached 40.5%. We conclude that the quickest and most sensitive method of detecting osteoporosis in CAPD patients is to measure bone mass in both forearm sites (33% distal and ultradistal), then in the femoral neck.

Zinc as a marker of nutrition in continuous ambulatory peritoneal dialysis patients.

Our aim was to show, in continuous ambulatory peritoneal dialysis (CAPD) patients, the relationships between zinc (serum level and dietary intake) and adequacy and duration of CAPD, age, and measures of nutrition. Serum zinc (12.2 +/- 1.8 mumol/L) was not significantly related to dietary zinc intake (9.9 +/- 2.5 mg daily), but depended on daily instilled (r = -0.331, p < 0.05) and effluent (r = -0.311, p < 0.05) dialysate volumes and on patient age (r = -0.304, p < 0.05). Positive correlations were seen between serum zinc level and laboratory (but not anthropometric) markers of nutrition: prealbumin (r = 0.349, p < 0.05), iron (r = 0.447, p < 0.05), transferrin saturation [(TSAT) r = 0.374, p < 0.05]. Additionally, zinc intake was positively related to serum ferritin level (r = 0.370, p < 0.05). Serum zinc level positively influenced blood morphology [correlation with hemoglobin (r = 0.287, p < 0.05) and mean corpuscular hemoglobin concentration (r = 0.361, p < 0.05)]. Zinc intake showed negative correlations with serum levels of total cholesterol (r = -0.373, p < 0.05) and vitamin E (r = -0.504, p < 0.05), and a positive correlation with HDL: total cholesterol ratio (r = 0.338, p < 0.05). Mean values of three latter parameters were out of the normal limits (total cholesterol: 219.2 +/- 47.0 mg/dL; vitamin E: 1.91 +/- 0.82 mg/dL; HDL: total cholesterol ratio: 16.7 +/- 5.1). We conclude that, in CAPD patients, zinc is a marker of nutrition showing beneficial effect on serum iron parameters, blood morphology, lipid profile, and elevated vitamin E concentration. Zinc supplementation is needed for approximately 16% of CAPD patients, especially older patients and those requiring higher dialysate volumes.

Parathyroid hormone contributes to variations in blood morphology in diabetic and non diabetic patients treated with continuous ambulatory peritoneal dialysis.

The present study looked for variations in blood morphology between diabetic patients (group I, n = 7) and non diabetic patients (group II, n = 16) treated with continuous ambulatory peritoneal dialysis (CAPD). A subsequent trial sought to find a reason for discrepancies in the results between the two groups. The patients in both groups and similar ages, CAPD durations, and erythropoietin dosages. Nutrition, CAPD adequacy, serum iron and ferritin levels, total iron binding capacity (TIBC), transferrin saturation (TSAT), red blood cells (RBCs), mean corpuscular hemoglobin (MCH), mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC), hemoglobin (Hb), hematocrit (Hct), white blood cells (WBCs), total lymphocyte count (TLC), platelets (PLTs), and serum intact parathyroid hormone (PTH) were evaluated every three months. The mean result of each parameter was obtained in every patient as representative for the entire CAPD course. Means and standard deviations for all respective parameters were then calculated for the two groups and compared. In patients with diabetes as compared with patients without diabetes, significantly higher numbers of RBCs, WBCs, and PLTs were seen, as were higher values for Hb and Hct and a lower serum PTH concentration. Values for WBCs, PLTs, and MCH obtained in all patients (n = 23) were correlated with serum intact PTH (r = -0.520, p = 0.011; r = -0.422, p = 0.045; and r = -0.436, p = 0.037 respectively). When data obtained in the patients receiving erythropoietin were excluded and the correlation analysis was repeated for the 10 remaining patients, a correlation between serum PTH and RBCs was found (r = -0.685, p = 0.029). With comparable age, renal function, nutrition, erythropoietin dosage, iron indices, and CAPD adequacy, duration, and outcome, higher parameters of blood morphology in diabetic patients may be related to lower levels of serum intact PTH, indicating no or only mild secondary hyperparathyroidism. Patients with diabetes usually show smaller disturbances in PTH level than do non diabetic uremic patients on CAPD. Better peripheral morphology indices in the group with diabetes can be expected when other factors affecting hematologic status are similar.

[A role of serum ferritin estimations in continuous ambulatory peritoneal dialysis patients]. / Znaczenie oznaczania stezenia ferrytyny w surowicy chorych leczonych ciagla ambulatoryjna dializa otrzewnowa.

The aim of our studies was to establish an aspect of pathophysiology that is specially indicated by serum ferritin level in continuous ambulatory peritoneal dialysis (CAPD) patients. In 50 CAPD patients serum ferritin level was related to other serum indicators of iron status as well as serum level of C-reactive protein (CRP), peripheral blood morphology (including RBC indices), serum lipid profile, anthropometrical and laboratory parameters of nutritional status, parameters of dialysis adequacy and dietary food intake. In examined CAPD patients serum ferritin concentration was elevated (median 448, range 25-5334 ng/ml). Statistically significant correlations between serum ferritin level and other examined parameters included positive correlation with CRP (r = +0.389) and negative correlation with transferrin (r = -0.462), RBC (r = -0.441), haemoglobin (r = -0.412), haematocrit (r = -0.483), total cholesterol (r = -0.580) and LDL-cholesterol concentration (r = -0.442). There were also positive correlations with daily effluent volume and dietary food intake. Our studies show that in CAPD patients an elevated serum ferritin level is an indicator of inflammatory status, protein malnutrition, and inadequate erythropoiesis, despite normal or nearly normal mean levels of other serum iron parameters. On the other hand, serum ferritin level increases with greater food intake.

Amino-acid-based dialysis solution changes leptinemia and leptin peritoneal clearance.

In continuous ambulatory peritoneal dialysis (CAPD) patients, nutritional parameters, appetite, and transperitoneal solute movement can be modified by treatment with amino-acid-based dialysis solution (AADS). Because leptin is involved in energy expenditure and appetite regulation, we decided to examine the influence of AADS on serum and dialysate leptin concentrations. We prospectively evaluated AADS influence on leptinemia and peritoneal transport indices in CAPD patients. Nine clinically stable patients (7 males, 2 females), mean age 55.4 +/- 10.5 years, who had been treated with CAPD for 6.1 +/- 5.8 months, were studied. Examinations were conducted before treatment with 1.1% AADS (period I), after 3 months of AADS administration (period II), after 6 months of AADS administration (period III), and at 3 months after AADS discontinuation (period IV). The primary outcome measure was concentration of leptin in serum and dialysate. Secondary measures included anorexia incidence, nutrient intake, and nutritional parameters. Dialysate-to-plasma ratio (D/P), peritoneal excretion, and clearance (PCl) of leptin were calculated. After 3 months of AADS administration (period II), leptinemia was transiently lower (9.8 +/- 6.2 ng/mL vs 17.1 +/- 14.2 ng/mL, p = 0.017), while D/P (0.51 +/- 0.44 vs 0.23 +/- 0.19, p = 0.012), peritoneal excretion (72.9 +/- 85.4 micrograms/day vs 37.2 +/- 32.3 micrograms/day, p = 0.015), and PCl (4.02 +/- 3.40 mL/min vs 1.75 +/- 1.32 mL/min, p = 0.008) of leptin were higher than measurements obtained at entry. Anorexia incidence and daily protein and energy intakes showed no significant changes during the study. Total body mass, body mass index, and plasma concentrations of total protein and of albumin increased significantly during AADS treatment. A significant positive relation of leptinemia to total fat mass was observed when AADS was not used (periods I and IV). We conclude that administration of AADS in CAPD patients causes a transient decrease in leptinemia and increases in peritoneal excretion and in PCl of leptin, as well as dissociation of the physiological relationship between serum leptin level and total fat mass.

Polyglucose dialysis solution influences serum iron parameters.

Owing to the lack of data dealing with the influence of polyglucose dialysis solution (PG-DS) on serum indicators of iron status, our study aimed at examining this problem in patients receiving PG-DS for the overnight exchange during treatment with continuous ambulatory peritoneal dialysis. We evaluated serum concentrations of iron, ferritin, and transferrin, total iron binding capacity (TIBC), and transferrin saturation (TSAT) at 1.6 +/- 0.8 months before introducing 7.5% PG-DS for an overnight 2 L exchange lasting about 10 hours (period I, n = 14), after 1.2 +/- 0.6 months of PG-DS administration (period II, n = 14), after 4.4 +/- 0.8 months of PG-DS administration (period III, n = 11), after 8.8 +/- 2.2 months of PG-DS administration (period IV, n = 9), and at 2.0 +/- 0.6 months after PG-DS discontinuation (period V, n = 11). Interference owing to PG-DS in laboratory determinations of serum iron parameters was excluded. Indices of nutritional status were also evaluated in all study periods. Significant differences in iron parameters were seen between periods I and III, or I and IV for transferrin (212 +/- 41 mg/dL vs 253 +/- 36 mg/dL), TIBC (304 +/- 40 micrograms/dL vs 338 +/- 31 micrograms/dL) and TSAT (34% +/- 15% vs 24% +/- 4%). After PG-DS withdrawal, these parameters all returned to pre-treatment values. Improvement in nutritional status was indicated by increases in total body mass (73.9 +/- 15.6 kg vs 77.4 +/- 13.8 kg), lean body mass (54.5 +/- 9.7 kg vs 56.9 +/- 8.5 kg), and serum total protein concentration (61.7 +/- 10.8 g/L vs 70.5 +/- 8.0 g/L). We conclude that serum transferrin concentration increases during PG-DS administration without enhanced iron binding to transferrin. An increase in transferrin level can be related to improved nutritional status.

Polyglucose dialysis solution influences serum activity of amylase and of lipase differently.

Polyglucose dialysis solution (PG-DS) decreases serum amylase activity owing to interference in the analytical method. The interference can make it difficult to diagnose pancreatitis. Our aim was to check whether, during PG-DS administration, serum lipase activity changes simultaneously with serum amylase activity, and, if so, what the reason is for the detected change. Studies were started in 14 continuous ambulatory peritoneal dialysis (CAPD) patients in whom 7.5% PG-DS was applied for the overnight exchange. In addition to standard clinical and laboratory data, serum activity of lipase and of total amylase were evaluated at 1.6 +/- 0.8 months before PG-DS introduction (period I, n = 14), after 1.2 +/- 0.6 months of PG-DS administration (period II, n = 14), after 4.4 +/- 0.8 months of PG-DS administration (period III, n = 11), after 8.8 +/- 2.2 months of PG-DS administration (period IV, n = 9), and at 2.0 +/- 0.6 months after PG-DS discontinuation (period V, n = 11). The PG-DS was also added to serum from CAPD patients with known activity of amylase and of lipase. Immediately and 3 hours after PG-DS addition, a significant decrease in total amylase activity was seen; lipase activity was unchanged. In consecutive study periods, the results (median and range) were: for lipase activity--50 U/L (12-131 U/L), 59 U/L (25-160 U/L; p < 0.05 vs period I), 73 U/L (26-158 U/L; p < 0.05 vs period I), 66 U/L (30-203 U/L; p < 0.05 vs period I), and 44 U/L (15-112 U/L); for amylase activity--81 U/L (43-249 U/L), 14 U/L (5-82 U/L; p < 0.05 vs period I and period V), 15 U/L (5-192 U/L; p < 0.05 vs period I), 15 U/L (10-93 U/L; p < 0.05 vs period I and period V), and 118 U/L (4-221 U/L). An increase in serum lipase activity over the normal range (27-65 U/L) was not accompanied by clinical symptoms of pancreatic dysfunction, but rises were simultaneously shown in blood urea nitrogen, in serum level of creatinine and of total calcium, and in calcium phosphorus product. Our results confirm PG-DS influence on amylase determinations, exclude PG-DS interference in lipase measurements, and indicate that long-term PG-DS administration influences pancreatic exocrine function at a subclinical level.