The role of aluminum accumulation in articular tissues of patients affected by dialysis-associated arthropathy (DAA) is questioned. The aim of this work is to identify the nature of these aluminum accumulations by the use of secondary ion mass spectrometry (SIMS). Al/Si ratios of about 1, measured by SIMS, strongly suggest for the first time the presence of aluminum silicates and possibly aluminum hydroxides in amyloid synovial tissue and articular cartilage of 1 patient with DAA and aluminum intoxication. This is thermodynamically consistent with the total dissolved Al and Si contents and pH measured in the synovial fluids. These results are similar to the abnormal Al distribution recently found by SIMS in the forebrain of chronic renal dialysis patients and to the amorphous aluminum silicates identified in the core of senile plaques in Alzheimer's disease.

To assess the prevalence and the incidence of hepatitis C virus (HCV) in a dialysis unit, we prospectively tested for anti-HCV in chronic hemodialysis patients and staff members since January 1989, using a first generation assay. Incidence was nil in staff and low in patients (3.7% in 89, 1% in 90), and prevalence was 30% in patients. In January 1991 blood samples from 115 patients were tested by first (EL1) and second generation (EL2) ELISA (Ortho Diagnostic System). Positive subjects were tested by a RIBA-2 confirmation test. Fifty-three patients were negative by all tests. Positive tests were observed in 62 patients (54%) including 36 positive in EL1 and EL2, and 26 only by EL2. All positive patients were reactive by RIBA-2 but nine were classified undetermined (only one positive band). In five patients reactivity of antibodies to 5-1-1 and C-100-3 gradually declined during the study. Second generation tests gave a better correlation with time on dialysis and blood transfusion. We conclude that second generation tests for HCV are more accurate for estimating true prevalence of HCV infection in hemodialysis units.

responsible for the production of IgG3. Further studies are needed to clarify the relationship of the low IgG3 level and susceptibility to infection. In this study we report preliminary results of treatment of patients with recurrent infections and low IgG3 levels. Double-blind placebo-controlled trials are needed to conclusively demonstrate the efficacy of prophylactic antibiotics and/or IVIG therapy in this patient group.

The phosphate kinetics during bicarbonate dialysis (BCD) and Acetate-free Biofiltration (AFB) were determined in 3 stable regular dialysis patients. These patients were switched to a 6-month period of AFB after a 12-month period of BCD. The plasma levels of phosphate, urea, and bicarbonate, and mass removal of phosphate and urea were measured every hour, during 3 consecutive dialysis sessions on BCD and AFB. The plasma phosphate behavior revealed a peculiar form with two main components, which differed from that of urea. The plasma phosphate level fell sharply during the first 2 hours of treatment, and then remained at a plateau towards to the end of the session. The plasma bicarbonate levels during the treatment sessions in the case of AFB were significantly higher than that in BCD. The actual mass removal in AFB was similar to that BCD, despite a significantly lower value of pre-plasma phosphate. A high ultrafiltration rate and better control of acidosis might be the reason for the better performance of phosphate mass removal in AFB. Better control of phosphatemia due to AFB can lead to a reduction in the amount of phosphate binders which have several untoward side effects.

The authors report the clinical history of a seventeen years old boy with renal failure treated with chronic haemodialysis since eleven and a half years of age. Growth velocity was 1.5 cm/year. The stature was below 5 SD as compared to the mean for the age. Hormonal measurements showed a complete growth hormone (hGH) deficiency and hyperparathyroidism. Thyroid, adrenal and gonadic secretions were normal, but the responses of TSH and prolactin to TRH were abnormal, showing an hypothalamic disturbance. hGH treatment, with thyroxin substitution, enhanced growth velocity up to 4 cm/year. Respective influences of hGH treatment, puberty and hyperparathyroidism on the incomplete correction of growth velocity are discussed.

Adverse reactions, such as skin flush and pruritus, have been observed among hemodialyzed (HD) patients. A potential relationship between hemodialysis and allergic phenomena prompted us to investigate some allergologic parameters. Total IgE, specific IgE antiethylene oxide and anti-isocyanate toluene diisocyanate, and in vitro spontaneous histamine release (SHR) were measured in 105 long-term stable HD patients. Thirty-two of the patients had occasionally developed skin flush reactions and/or pruritus during dialysis sessions. Blood samples were taken at the start of dialysis, sera were kept frozen until assay, and in vitro SHR was performed on washed leukocytes at 37 degrees C for 40 minutes. A high (range, 20% to 80%) and reproducible in vitro SHR was observed among 24% of patients. No correlation was found between SHR and the type of dialysis membrane used (copolymer of acrylonitrile-methallyl-sodium sulfonate, cuprophan, and polysulfone). High SHR (i.e., greater than 20%) was observed mainly among patients with detectable antiethylene oxide IgE antibodies (p less than 0.001). High levels of IgE (greater than 300 ng/ml), specific IgE antibodies, and a high in vitro SHR were all observed concomitantly in 26% of the patients with skin flush reactions and/or pruritus, whereas all three of these parameters together were present in only 3% of the symptom-free patients. To our knowledge, this is the first time that a high in vitro SHR has been described among HD patients, and putative correlations with in vivo phenomena are discussed.

In vivo induction of interleukin-1 (IL-1) production during hemodialysis was investigated by measuring IL-1 activity in monocyte lysates from 59 patients undergoing long-term maintenance hemodialysis with complement activating and non-complement activating devices. In patients dialyzed with new hollow-fiber cuprophane dialyzers, predialytic (T0) monocyte-associated IL-1 activity was 12.5 +/- 3.0 U/ml (mean +/- SEM), a value that was higher than that found in normal individuals (2.85 +/- 0.85 U/ml; P less than 0.0025) and in non-dialyzed patients with chronic renal failure (0.95 +/- 0.85 U/ml, P less than 0.0001). Cell-associated IL-1 activity was consistently increased after five hours of dialysis with cuprophane membranes (42.4 +/- 5.5 U/ml, P less than 0.0005). Systemic complement activation was demonstrated by the finding of increased plasma levels of C3adesArg antigen during dialysis. In patients dialyzed with high permeability polyacrylonitrile and polysulfone membranes, no intradialytic change in cell-associated IL-1 and no complement activation occurred. However, the mean predialytic values of monocyte-associated IL-1 in these patients (that is, 32.9 +/- 5.6 U/ml and 38 +/- 5.65 U/ml for the polyacrylonitrile and the polysulfone groups, respectively) were higher than the predialytic levels of cell-associated IL-1 in the patients from the cuprophane group (P less than 0.0025). Monocytes obtained at the beginning and five hours of dialysis from patients dialyzed with polyacrylonitrile devices, and monocytes obtained at five hours but not at the beginning of dialysis from patients dialyzed with cuprophane membranes, spontaneously released extracellular IL-1 after 24 hours of culture in serum free conditions.(ABSTRACT TRUNCATED AT 250 WORDS)

Pruritus is frequently observed in hemodialyzed patients; its etiology seems to be multifactorial. Increased plasma histamine levels have been reported in chronic renal failure. As histamine is a potent inducer of pruritus. The authors investigated its concentrations and kinetics in plasma of stable hemodialyzed patients.