摘要:

We simulated touch contamination of peritoneal dialysis fluids perfused through an in vitro system with a modified Robbins’ device (MRD) and Y-connecting tubings, to study the pathogenesis of bacterial biofilm (BB) growth on Tenckhoff catheter (TC) discs. The spike ends of Y-connecting sets were dipped in a suspension of freshly cultured cells of Staphylococcus epidermidis (3X108 cfu/ml), and connected to 2 litres of 0.5 % dianeal solution which was perfused through the MRD with plugs containing TC discs. Four simulated clinical exchanges were performed with or without prior flushing and/or bleach treatment of the Y sets. Control experiments were done with fresh Dianeal solution with no contamination, flushing, or bleach treatment. BB growth on the TC discs was examined by scanning electron microscopy (SEM) and transmission electron microscopy and quantitated by routine culture of scrapings from the discs. We noted that touch contamination of dialysis fluids via the spike ends of the connecting sets can generate dense BB growth on TC discs in this experimental system (62 ± 8% by SEM and 10.2 ± 8.3 X 103 cfu/ml by culture). This growth of BB was significantly reduced by flushing the Y set with sterile Dianeal solution (24.3 ± 3% by SEM and 5.7 ± 3.5 X 101 cfu/ml by culture) and was absent by bleach treatment. We conclude that although bleach treatment of Y sets can prevent BB growth, the ‘flushing’ procedure alone can significantly reduce BB growth on TC from touch contamination of dialys

ISSN:0250-8095    

DOI:10.1159/000168149

出版商:S. Karger AG    

年代:1990

数据来源: Karger

摘要:

A modification of the urine osmolal gap was evaluated as an estimate of urine [NH+4]. We proposed that: Urine [NH-4] =Urine osmolality – [2(Na+ + K+) + urea + glucose]/2 Spot urine samples were collected from normal volunteers and from individuals with ketonuria; the modified urine osmolal gap as well as two other previously described estimates of urine [NH+4] were compared with measured urine [NH+4]. There was a significant positive linear correlation between the urine [NH+4] and the modified urine osmolal gap in normal volunteers (r = 0.81; p < 0.01) and in individuals with ketonuria (r = 0.93; p < 0.001). The originally described urine osmolal gap greatly overestimated the urine [NH+4] but also showed a significant correlation. The urine anion gap was not a valid estimate of urine [NH+4] within the range of values measured in our subjects. The modified urine osmolal gap is an improvement over previously described estimates of urine [NH+4] and can be used as a single calculation in place of the other tw

ISSN:0250-8095    

DOI:10.1159/000168150

出版商:S. Karger AG    

年代:1990

数据来源: Karger

摘要:

We assessed the utility of bioelectric impedance plethysmography (BIA) for measuring acute volume changes and body composition in patients with renal disease. Chronic hemodialysis and peritoneal dialysis patients were evaluated before and after dialysis. Total body water, as measured by BIA, predicts body weight. Acute changes in body water, induced by dialysis, are not predicted well by data derived from BIA. Body fat (%) and fat-free mass (%), determined by anthropometry, are predicted well by body composition data derived by BIA. BIA is useful for assessing body composition in this population, but must be cautiously applied to the measurement of acute volume changes.

ISSN:0250-8095    

DOI:10.1159/000168151

出版商:S. Karger AG    

年代:1990

数据来源: Karger

摘要:

Peritoneal macrophages (PM) perform first-line defense activity against peritonitis, the most important complication in continuous ambulatory peritoneal dialysis (CAPD) therapy. Our longitudinal study has compared the PM function in 20 uremic patients during periods free of peritonitis since they started CAPD therapy in January 1987. The results showed that at the initiation of CAPD, there was a higher bactericidal activity, phagocytosis index, H2O2 production and interleukin-1 (IL-1), γ-interferon (IFN-γ) and tumor necrosis factor (TNF) production ability and MHC expression. As time went on, these progressively decreased, and by 9 months after CAPD therapy had started they were significantly lower than at the beginning. During the 1.5-year follow-up period, there was a significantly increased peritonitis rate in the period 6 months after the beginning of CAPD than in the period before the 6th month (88.3 vs. 11.7% respectively; p < 0.001). These results indicate that PM of new CAPD patients have a more active function than those of established patients. The established patients had a greater risk of peritonitis. A comparison of the immunological profiles of PM from patients who had a peritonitis history shows that phagocytosis index, bactericidal activity and IL-1 and TNF production of PM were significantly decreased during the period free of peritonitis. This result suggests that these parameters may serve as an indicator in developing peritonitis.

ISSN:0250-8095    

DOI:10.1159/000168152

出版商:S. Karger AG    

年代:1990

数据来源: Karger

摘要:

The morphometric investigation of the proximal and distal tubules, the cortical interstitium, the inter-tubular capillaries, the renal corpuscles and the juxtaglomerular apparatuses (JGAs) in 56 cases in the oligoanuric, polyuric, and normuric phases of human acute renal failure (ARF), 6 cases of myeloma kidney with clinically confirmed ARF and 21 control kidneys revealed the following: (1) The main pathological change in human ARF is swelling of the epithelial cells of the proximal and distal tubules. Necrosis of these cells was observed in some cases but usually only as single cell necroses. (2) The interstitium of the cortex and of the outer stripe of the outer medulla is significantly widened in most cases of ARF. (3) In proximal tubules proximal to occluding casts (which were observed only in the plasmacytoma cases), the lumina are not widened but are narrower than normal, and the cross-sectional area of the epithelium is not greater but smaller than normal. (4) The JGAs were significantly larger in kidneys in the oligoanuric phase of ARF (with 1 exception) than in normal kidneys. In the normuric and polyuric phases they were slightly (not significantly) smaller than normal. In myeloma kidneys with occluding casts and/or diffuse interstitial fibrosis, the JGAs were significantly smaller than normal. From these findings it is concluded that: (1) The fall in glomerular filtration rate (GFR) in the postshock phase of ARF is not caused by nonselective back-diffusion of the primary urine through necrotic tubules or by compression of the lumina of the proximal and distal tubules by interstitial edema. A fall in GFR associated with occluding casts in the distal tubules is found only in the myeloma kidney and does not lead to widening of the proximal tubules but to tubular atrophy and narrowing of the lumen. (2) The casts seen in the lumina of the ascending limb of Henle’s loop in some cases of ARF, which consist of hemoglobin, Tamm-Horsfall protein or desquamated blebs, do not occlude the lumen, since they are not associated with atrophy or luminal dilatation of the proximal tubules. (3) The JGAs with their secretory product renin-angiotensin II, together with adenosine, which is released in kidneys with ischemic or toxic damage, play a critical role in the pathogenesis of ARF. (4) In myeloma kidneys with ARF, in which the JGAs are markedly atrophic, the potentiated effect of adenosine that has been observed with a chronic absence of urine flow probably leads to a progressive, irreversible drop in GFR associated with tubular atroph

ISSN:0250-8095    

DOI:10.1159/000168153

出版商:S. Karger AG    

年代:1990

数据来源: Karger

摘要:

A new type of amyloidosis, predominantly osteoarticular, has recently been recognized in uremic patients on hemodialysis, (β2-microglobulin being the major constituent protein. Nowadays, it is not clear whether the amyloid deposition is limited to osteoarticular structures or whether it has a systemic character. In order to investigate the extension of dialysis amyloidosis, we studied 26 patients receiving hemodialysis treatment (mean time 12.2 years) for chronic renal failure due to nonamyloid nephropathy and who were affected by symptomatic dialysis amyloidosis. Twenty-two patients developed a carpal tunnel syndrome, and amyloid arthropathy was present in 21. Subcutaneous abdominal fat aspiration, rectal and skin biopsy, and two-dimensional echocardiography were performed in most of the patients, searching for the visceral involvement. Surgical pieces (one stomach and two colon) and three necropsies of symptomatic patients were included in the systemic investigation. Also, we studied five necropsies of patients without articular symptoms. Histological confirmation of amyloid visceral involvement was demonstrated in 15 (58%) of the 26 patients studied. When positive two-dimensional echocardiograms were included, the percentage increased to 81 %. No differences in the rate of visceral involvement could be found between the two clinical groups (with and without carpal tunnel syndrome). Two-dimensional echocardiography represents the most useful tool to search for the visceral involvement of β2-microglobulin amyloidosis, followed by abdominal fat aspiration and rectal biopsy. Amyloid deposits were resistent to potassium permanganate treatment and reacted with antihuman β2-microglobulin (avidin-biotin-peroxidase metho

ISSN:0250-8095    

DOI:10.1159/000168154

出版商:S. Karger AG    

年代:1990

数据来源: Karger

摘要:

During the period from April 4, 1988, to April 20, 1988, nine pyrogenic reactions and five gram-negative bacteremias occurred in 11 patients undergoing dialysis. All pyrogenic reactions and gram-negative bacteremias occurred among patients in whom a reprocessed dialyzer was used. The rate of pyrogenic reactions or bacteremias per 100 sessions using a reprocessed dialyzer was higher than in sessions during which a new dialyzer was used (4.5 vs. 0; p = 0.03). Dialyzers were manually reprocessed with 2.5% Renalin germicide. The Renalin concentrations varied widely in 12 dialyzers stored after manual reprocessing during the epidemic period (0.9–4.2%); the median endotoxin concentrations varied from 0 to 246 ng/ml and were higher in dialyzers with Renalin concentrations < 1.0% than in dialyzers with higher concentrations (p = 0.01). Experiments using a dilution technique described by a technician resulted in Renalin concentrations ranging from 1.4% at the surface to 3.5% at the bottom of the preparation container. These findings suggest that failure to adequately admix Renalin during dilution may be associated with low levels of disinfectant, high levels of bacteria and endotoxins in dialyzers, and outbreaks of pyrogenic reactions and gram-negative bacteremias in dialysis patient

ISSN:0250-8095    

DOI:10.1159/000168155

出版商:S. Karger AG    

年代:1990

数据来源: Karger

摘要:

Twelve stable haemodialysis patients were divided into two groups and given recombinant human erythropoietin (r-HuEPO) for 14 weeks either intravenously (i.v.) or subcutaneously (s.c). Dosage was 25 units/kg either thrice (i.v.) or twice (s.c.) per week for 7 weeks, and then 50 units/kg for a further 7 weeks. Response to s.c. therapy was comparable to i.v. despite a 33% lower weekly dosage, and was significant at both 7 (i.v.: 1.1 ± 0.3, mean ± SEM, p = 0.02; s.c: 0.8 ± 0.3 g/dl, p = 0.03) and 14 weeks (i.v.: 2.8 ± 0.5, p = 0.003; s.c: 2.6 ± 0.6 g/dl, p = 0.009). A correlation was observed between response to r-HuEPO and initial ferritin levels (r = 0.63, p = 0.04). One patient required an increase in antihypertensive medication and there was one arteriovenous fistula thrombosis. Results suggest that overall s.c. therapy is as effective as i.v. therapy, and that a good response with few side effects can be obtained using relatively low doses of r-H

ISSN:0250-8095    

DOI:10.1159/000168156

出版商:S. Karger AG    

年代:1990

数据来源: Karger

摘要:

Although hypermagnesemia purportedly lowers the anion gap (AG), we have shown previously that increases in the serum concentration of the unmeasured cation (UC) Mg due to therapeutic infusion of MgSO4 are not associated with AG reduction. To assess our hypothesis that increases in serum SO4 (unmeasured anion, UA) offset the effect of elevated serum Mg on the AG, we prospectively studied 11 patients receiving MgS04 intravenously for toxemia of pregnancy. After 6 h of MgSO4 infusion, serum Mg increased by 2.1 ± 0.2 (SE) mEq/1 (p < 0.001) without a significant decrease in the AG. Concomitantly, serum SO4 increased by 1.4 ± 0.2 mEq/1. Comparison of the renal handling of SO4 versus Mg showed a higher fractional excretion of the former, probably accounting in part for the smaller increment of serum SO4 than of Mg. Comparison of the change in serum SO4 minus that of Mg indicated that, on the average, 70% of the observed 1.0 ± 0.7 mEq/1 reduction in AG was accounted for by the observed changes in the two pertinent unmeasured ions. A small decrement in serum Ca probably was a quantitatively minor factor tending to obviate a greater decrease in AG. We conclude that hypersulfatemia attenuates the reduction in AG that would otherwise accompany MgSO4-induced hypermagnesem

ISSN:0250-8095    

DOI:10.1159/000168157

出版商:S. Karger AG    

年代:1990

数据来源: Karger

ISSN:0250-8095    

DOI:10.1159/000168158

出版商:S. Karger AG    

年代:1990

数据来源: Karger