Effects of Dialysis Membranes on the Kinetics of Tumor Necrosis Factor-α Production by Peripheral Mononuclear Cells in Chronic Hemodialysis Patients

To evaluate the biocompatibility of dialysis membranes, blood samples were collected from 10 hemodialysis patients immediately before dialysis and peripheral blood mononuclear cells were isolated. The 3.0 x 105 cells/ml were then passed 30 times through modules made of a polyethylene glycolgrafted cellulose membrane, a polyacrylonitrile membrane, and a polysulfone membrane. Expression of messenger RNA for tumor necrosi factor-α (TNF-α) was determined. Cells were also cultured for 2 h with and without lipopolysaccharide and TNF-α levels in the supernatant were measured.

TNF-α messenger RNA expression was significantly higher immediately after passage through the polyacrylonitrile membrane compared with the other membranes. Cells cultured without lipopolysaccharide, produced significantly less TNF-α after passage through the polysulfone membrane, while lipopolysaccharide significantly increased TNF-α production by cells passed through the polyacrylonitrile membrane. These results suggest that biocompatibility differs even among dialysis membranes believed to cause no complement activation.

Lipid-lowering therapy and coagulation/fibrinolysis parameters in patients on peritoneal dialysis

Patients on continuous ambulatory peritoneal dialysis (CAPD) often have abnormalities of lipid metabolism or coagulation and fibrinolysis, these patients may thus be more susceptible to atherosclerosis than those on hemodialysis. It has been reported that hypercoagulability and hyperfibrinolysis are correlated with abnormalities of lipid metabolism. Therefore, we investigated the effect of a decrease in lipids on the coagulation and fibrinolysis system in CAPD patients with hyperlipidemia who received lipid-lowering therapy. The patients included 5 men and 13 women, with a mean age of 52.5 years. Pravastatin sodium (10 mg/day) and ethyl icosapentate (1800 mg/day) were administered concomitantly for 8 weeks. Lipid levels and coagulation/fibrinolysis parameters were measured before and after therapy. The patients were divided into two groups depending on their response to therapy: responders showed a decrease in total cholesterol or triglycerides by at least 20% and non-responders showed less improvement. In the responders, the levels of protein C, tissue plasminogen activator/plasminogen activator inhibitor-I complex, factor XIII, alpha2-plasmin inhibitor, and D-dimer were significantly lower after therapy than before therapy. Protein C, factor XIII, and alpha2-plasmin inhibitor were also significantly decreased after therapy in non-responders, but the extent of the decrease was smaller. The plasminogen level was significantly increased after therapy in non-responders. These findings suggest that a decrease in lipid levels and/or some other action by lipid-lowering agents may correct abnormalities of coagulation and fibrinolysis in CAPD patients.

Apolipoprotein E polymorphism and renal disease

BACKGROUND

Lipid abnormalities are frequently found in end-stage renal disease (ESRD), and abnormal lipid metabolism may contribute to the progression of renal disease. Previous investigators have reported that apolipoprotein E (apoE) has an important role in lipoprotein metabolism and that the process of lipoprotein catabolism varies according to the apoE phenotype. In addition, the relative frequency of the apoE alleles is different among the races. In this study, we investigated the allele frequency of apoE phenotypes and evaluated the impact of apoE polymorphism on lipid profile in Japanese patients with renal disease.

METHODS

ApoE phenotypes were determined using isoelectric focusing and Western blotting in 592 Japanese patients with renal disease [86 out of 107 patients with glomerulonephritis had proteinuria of not less than 0.25 g per 24 hr and 485 with ESRD; 448 were on hemodialysis (HD), and 37 were on continuous ambulatory peritoneal dialysis (CAPD)]. The allele frequency and apoE phenotype distribution were estimated by the gene-counting method. Serum lipid parameters related to lipid metabolism were measured after at least a 12-hour fast.

RESULTS

The allele frequency of the three major apoE phenotypes (apoE2, apoE3, and apoE4) in 107 glomerulonephritis patients (epsilon 2; 0.037, epsilon 3; 0.860, epsilon 4; 0.103) was almost identical to that in the normal control population (epsilon 2; 0.036, epsilon 3; 0.848, epsilon 4; 0.115). However, 86 glomerulonephritis patients with proteinuria had higher allele frequency of apoE2 (epsilon 2; 0.052, P < 0.01) and apoE4 (epsilon 4; 0.140, P < 0.001) and lower allele frequency of apoE3 (epsilon 3; 0.808, P < 0.001) than the controls. Furthermore, ESRD patients had higher allele frequency of apoE2 (epsilon 2; 0.058, P < 0.01) and lower allele frequency of apoE4 (epsilon 4; 0.091, P < 0.05) than the controls. Higher prevalence of nephrotic syndrome was found in proteinuric glomerulonephritis patients with apoE2. The impact of apoE polymorphism on serum lipid profile in patients with glomerulonephritis, HD, and CAPD was different from that generally expected.

CONCLUSIONS

The higher frequency of apoE2 in ESRD patients suggests that apoE2 is a possible genetic predisposition to ESRD in a Japanese population. The impact of apoE2 and apoE4 on lipid profile in patients with renal disease was unique and different from that in the normal population.

Vancomycin therapy for treatment of peritonitis in outpatients on peritoneal dialysis

Vancomycin therapy is frequently used for peritonitis in patients on peritoneal dialysis, but the emergence of resistance has been reported. We evaluated the efficacy of a single intraperitoneal dose of vancomycin for peritonitis in peritoneal dialysis patients. We assessed 24 episodes of peritonitis in 16 patients, and compared clinical parameters between responders and nonresponders. Vancomycin was effective for 12 patients (18 out of 24 episodes, 75.0%). Nonresponders had a significantly higher initial C-reactive protein level and dialysis fluid leukocyte count, and the mean serum albumin over three months before onset was significantly lower than in responders. Patients with a serum albumin level 3.0 g/dl or more were significantly more likely to respond than those with a level less than 3.0 g/dl. In conclusion, it seems reasonable for peritonitis patients with a mild inflammatory response and a serum albumin 3.0 g/dl or more to receive intraperitoneal vancomycin on an outpatient basis.

Effects of dialysis membranes on the kinetics of tumor necrosis factor-alpha production by peripheral mononuclear cells in chronic hemodialysis patients

To evaluate the biocompatibility of dialysis membranes, blood samples were collected from 10 hemodialysis patients immediately before dialysis and peripheral blood mononuclear cells were isolated. The 3.0 x 10(5) cells/ml were then passed 30 times through modules made of a polyethylene glycol-grafted cellulose membrane, a polyacrylonitrile membrane, and a polysulfone membrane. Expression of messenger RNA for tumor necrosi factor-alpha (TNF-alpha) was determined. Cells were also cultured for 2 h with and without lipopolysaccharide and TNF-alpha levels in the supernatant were measured. TNF-alpha messenger RNA expression was significantly higher immediately after passage through the polyacrylonitrile membrane compared with the other membranes. Cells cultured without lipopolysaccharide, produced significantly less TNF-alpha after passage through the polysulfone membrane, while lipopolysaccharide significantly increased TNF-alpha production by cells passed through the polyacrylonitrile membrane. These results suggest that biocompatibility differs even among dialysis membranes believed to cause no complement activation.

Dose escalation induces tolerance to side-effects of erythropoietin in a patient with dialysis anaemia: case report

A 51-year-old woman began haemodialysis for chronic renal failure in February 1981. Symptomatic anaemia required treatment with recombinant human erythropoietin (rHuEPO) in February 1990 (3000 IU, twice weekly, intravenously). She developed influenza-like symptoms and treatment was withdrawn. In June 1994 rHuEPO was resumed at a very low dose of 100 IU subcutaneously three times weekly, and was increased gradually to 500 IU, without inducing any side-effects. At this dose the haematocrit was maintained at 22.0-25.0% and the symptoms of anaemia improved. In patients like ours, with influenza-like symptoms caused by rHuEPO therapy, dose escalation starting from an ultra-low dose may be effective in avoiding side-effects.

CAPD catheter rupture without deterioration

Continuous ambulatory peritoneal dialysis (CAPD) is associated with various problems, including damage to the CAPD catheter. We encountered catheter rupture around the titanium adaptor in a patient who had been on CAPD for 7 years. The area near the adaptor generally suffers damage secondary to deterioration of the silicon composing the catheter. However, stereoscopic and electron microscopic observation of the surface of the catheter revealed no deterioration. Instead, there were fine scratches around the site of rupture and the broken surface was rough. Since the patient did not protect the catheter with gauze near the titanium adaptor, it was probably damaged by the adaptor and then ruptured by some external force.

Fatal hepatic failure caused by miliary tuberculosis in a hemodialysis patient: case report

A 57 year-old male dialysis patient died soon after the onset of high fever, hypoglycemia, and disturbance of consciousness. Autopsy revealed granulomatous lesions associated with caseous necrosis mainly found in the liver, despite the absence of pulmonary changes on chest radiographs performed during the patients illness. It appears that tubercle bacilli were hematogenously disseminated mainly to the liver causing miliary tuberculosis without producing typical diffuse lesions in the lungs. Since tuberculosis is a common complication in hemodialysis patients, the potential development of atypical miliary tuberculosis should always be borne in mind.

Remnant-like particle cholesterol may indicate atherogenic risk in patients on chronic hemodialysis

Recently, involvement of remnant-like particle cholesterol (RLP-C) in atherosclerosis was reported, but this parameter has not been adequately investigated in hemodialysis (HD) patients. The present study investigated the relationship between the RLP-C level and total cholesterol (TC), triglycerides (TG), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), lipid peroxides (malone dialdehyde, MDA), apolipoprotein (Apo) A-I, and ApoB. In addition, the fractions of very low density lipoprotein (VLDL), intermediate density lipoprotein (IDL), LDL, and HDL in serum lipoproteins were determined by disk polyacrylamide gel electrophoresis. The relationship between the RLP-C level and three atherogenic indices was also studied. The RLP-C level in HD patients (8.2 +/- 6.7 mg/dl) was significantly higher than that in normal controls (2.7 +/- 1.3 mg/dl). The RLP-C level showed a significant positive correlation with the levels of TC, TG, LDL-C, MDA, ApoB, VLDL(%), and IDL(%), as well as a negative correlation with HDL(%). However, there was no correlation with age or the duration of HD. RLP-C also showed significant positive correlations with the (TC -HDL-C)/HDL-C ratio and the (VLDL + LDL)/HDL ratio, as well as a negative correlation with the ApoA-I/ApoB ratio. These results suggest that RLP-C may be a potential indicator of atherogenic risk in HD patients.

Immunohistochemical localization of apolipoprotein E in renal amyloidosis

To clarify the role of apolipoprotein E (apo E) in the formation of amyloid deposits, we examined specimens from 11 patients with renal amyloidosis who underwent renal biopsy by an immunohistochemical method using a monoclonal antibody (murine IgG1). Apo E was distributed in the amyloid deposits of all patients in a pattern similar to that obtained with Congo red staining. Strong positive staining for apo E was found on the amyloid deposits in the glomeruli. These results suggest that apo E is a common constituent of amyloid fibrils and that it may be a useful marker for immunohistochemical studies of systemic amyloidosis including renal amyloidosis.

Nicardipine hydrochloride suppresses DNA synthesis in human mesangial cells stimulated with recombinant human (rh) platelet-derived growth factor AA, rh interleukin-1 alpha, or rh tumor necrosis factor-alpha

In order to define the role of cytokines in mesangial cell pathophysiology, we measured the mitogenic activity of recombinant human platelet-derived growth factor AA (rhPDGF-AA), rh interleukin-1 alpha (rhIL-1 alpha) and rh tumor necrosis factor-alpha (rhTNF-alpha) in cultured human mesangial cells, and investigated the effect of the calcium channel blocker nicardipine hydrochloride on their cell mitogenic activity. DNA synthesis in mesangial cells, stimulated by rhPDGF-AA, rhIL-1 alpha or rhTNF-alpha, was measured using [3H]TdR up take and similar investigations, with nicardipine hydrochloride added to the above, were conducted. The results showed DNA synthesis in cultured human mesangial cells were stimulated by rhPDGF-AA, rhIL-1 alpha and rhTNF-alpha, and this effect was reduced by the addition of nicardipine hydrochloride. Since rhPDGF-AA, rhIL-1 alpha and rhTNF-alpha are released by the inflammatory cells which infiltrate glomeruli, these cytokines may be involved in the mechanisms of mesangial cell proliferation observed in immune-mediated mesangial proliferative glomerulonephritis. Nicardipine hydrochloride reduced DNA synthesis in cultured human mesangial cells in response to these cytokines, suggesting possible application in medical therapy for immune-mediated mesangial proliferative glomerulonephritis.

Glomerulocystic kidney disease in a young adult

We report an 18-year old woman who had glomerulocystic kidney disease (GCKD) without a family history of renal disease or hypertension and no known congenital abnormalities. Her renal function was normal. Renal biopsy showed cystic dilatation of the Bowman's spaces and atrophy of the glomerular tufts. Electron microscopy revealed specific changes in the basement membranes of noncystic glomeruli, suggesting a congenital origin for her renal pathology. This relatively rare case contrasts with the usual presentation of GCKD in neonates or children.