摘要:

In a retrospective, double-blind study, we analyzed, utilizing an immunohistochemical technique, the distribution of Endothelin (Et) in 20 renal biopsies of 17 children with nephrotic syndrome (NS): 9 cases of steroid-responsive and 8 of steroid-resistant minimal-change disease (MCD) and 3 cases of focal segmental glomerulosclerosis (FSGS). Thirteen out of 20 biopsies (9/9 steroid-responsive MCD and 4/8 steroid-resistant MCD) showed a weak positivity of the vascular endothelial cells, as the normal renal tissue samples obtained from tumor nephrectomies. Seven out of 20 biopsies, all steroid-resistant NS, showed a marked positivity of the vascular endothelium and of the tubules and/or interstitial cells. In 4 of these 7 cases (1 MCD, 3 FSGS) a positivity of glomeruli was also revealed. The positivity of vascular endothelium seems to confirm its central role in Et production. The marked immunoreactivity detected in the endothelial cells and other renal components reveals a local increase in Et in some steroid-resistant MCD and, particularly, in FSGS. These preliminary observations suggest that Et may participate (cause or epiphenomon) in the mechanisms underlying the development of glomerulosclerosis and the progression of renal damage.

ISSN:0250-8095    

DOI:10.1159/000168707

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

Uremic compounds are known to displace phenytoin from protein binding, resulting in a higher concentration of the pharmacologically active free fraction of phenytoin. The true chemical identities and molecular weight range of all these compounds are still unknown. We demonstrated that indoxyl sulfate and hippuric acid, which are found at high concentrations in uremic patients, can only partially explain the elevated free phenytoin concentration. Other known uremic compounds, guanidine, methylguanidine, and guanidinosuccinic acid, do not displace phenytoin from the protein-binding sites. Uremic compounds from sera of patients on maintenance hemodialysis were removed using activated charcoal. These compounds were then backextracted from activated charcoal using methanol and analyzed by fast atom bombardment mass spectroscopy. Mass spectra of uremic sera showed no peak over m/z 450, indicating that midmolecular uremic toxins are not involved in displacing phenytoin from protein binding. We also observed additional peaks in the mass spectrum of uremic compounds when compared with the normal serum extract, indicating the presence of several endogeneous compounds in uremic sera, as expected.

ISSN:0250-8095    

DOI:10.1159/000168708

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

Short-course therapy for pediatric urinary tract infection (UTI) remains controversial. The present study was undertaken to compare the effectiveness of cefuroxime axetil (Ceftin®) as short-course (2-day) versus conventional (10-day) therapy for uncomplicated pediatric UTIs. In a randomized, controlled, prospective study, we enrolled 50 children, 2-11 years of age, to receive oral cefuroxime axetil, 125 mg twice a day, for either 2 or 10 days. UTI was defined as at least 105 colonies/ml of a single pathogen isolated on clean catch, or at least 104 colonies/ml on a catheterized specimen. A 10-fold or greater reduction in colony count ofthe initially isolated organism (3-5) days after stopping therapy was considered a bacteriologic success, as long as the absolute colony count was below the threshold for UTI described above. Patients were followed for 15 months with multiple repeat urine cultures and radiologic studies. Twenty-five ofthe 50 patients enrolled were withdrawn, including 12 for initially inadequate colony counts. Eight of 12 patients in the short-course group (67%), versus 12 of 14 in the conventional-therapy group (86%), were initial bacteriological successes, a nonsignificant difference. All 37 initially isolated uropathogens were sensitive to cefuroxime axetil in vitro. Cefuroxime axetil is an effective antimicrobial for uncomplicated pediatric UTIs. Two-day therapy with cefuroxime axetil appears to be as effective as 10-day therapy, although sample size was limited in this study

ISSN:0250-8095    

DOI:10.1159/000168709

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

Eighteen patients with chronic renal failure had their cardiac status monitored during hemodialysis (HD). Ten studies were carried out using an ambulatory nuclear vest to assess ejection fraction (EF), heart rate (HR), relative end-systolic (ESV) and end-diastolic (EDV) volumes every 60 s. A total of 36 episodes of EF falls occurred in 9 patients, all asymptomatic. These EF falls were associated with a rise in ESV, while HR, BP, and EDV remained unchanged. The EF falls correlated best with the volume of ultrafiltrate removed. Ten patients had on-line ST-segment monitoring with sestamibi injection either at the time of ST depression (STD) or at the end of dialysis, if no STD occurred, in order to detect the presence of transient ischemia. Seven often patients had perfusion defects after dialysis, with STD occurring in 3 of 10 patients. Pre-dialysis imaging was available in only 8 of 10 patients, and 6 of these patients had perfusion defects. Changes in perfusion defects were not significantly different in the 3 patients with STD compared with those without STD. EF falls and perfusion defects are common in HD patients even in the absence of known coronary artery disease; however, ST segment monitoring is not a sensitive tool for its detection. These changes in function and perfusion may represent myocardial ischemia and contribute to the high incidence of cardiovascular morbidity and mortality in this patient population.

ISSN:0250-8095    

DOI:10.1159/000168710

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

Imipenem/cilastatin sodium is a new thienamycin class of antibiotic with a broad spectrum of bactericidal activities. It may be a suitable single first-line therapy for the treatment of peritonitis in continuous ambulatory peritoneal dialysis (CAPD) patients. Fifty episodes of CAPD peritonitis were treated with imipenem/cilastatin sodium. On presentation, all patients were given an intravenous loading dose of 1 g of imipenem/cilastatin sodium followed by intraperitoneal imipenem/cilastatin sodium for 10 days. During 1989 (30 episodes), 20 mg imipenem/cilastatin sodium was added to each 2-liter bag of peritoneal dialysis (PD) fluid for 10 days. The primary response rate as defined by polymorphonuclear neutrophils < 100/ml in PD fluid was 90%. Unfortunately, 17% of the peritonitis relapsed within 14 days of stopping antibiotic. The complete cure rate without relapse was therefore 73%. During 1990 (20 episodes), 100 mg imipenem/cilastatin sodium was added to each 2-liter bag of PD fluid for 10 days. The primary response rate was 95%, the complete cure rate without relapse was 85%. Imipenem/cilastatin sodium is an effective single first-line antibiotic for the treatment of peritonitis in CAPD.

ISSN:0250-8095    

DOI:10.1159/000168711

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

We report the long-term follow-up of 5 patients (4 kidney, 1 heart recipients) having a pretransplant monoclonal gammopathy of undetermined significance (MGUS). The follow-up of MGUS before transplantation was 41.2 ± 40.7 months (range 2-108). The monoclonal component isotype was IgG-kappa in 3 cases and IgA-lambda in 2. The pretransplant level of the monoclonal component was 11.1 ± 4.8 g/l (range 4-15.6). The transplant recipients who had MGUS were older than our other transplant patients. All but one of them received ciclosporine A. They did not experience more rejection or infectious complications than the others. Their posttransplant follow-up ranged from 3 to 9 years. The monoclonal component level remained stable in 2 patients but increased in 3 (33-225%). This was not correlated with bone marrow plasmocytosis. Two patients developed smoldering myeloma indicated by bone marrow immunochemistry studies which showed monomorph monoclonal plasma cells; nevertheless, they did not have cytopenia or bone lytic lesions. This percentage is higher than in the Kyle study but we cannot assume that it is due to ciclosporine A since our study sample is too small. In conclusion, MGUS is not a contraindication to organ transplantatio

ISSN:0250-8095    

DOI:10.1159/000168712

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

Recent in vitro and in vivo studies have shown that calcium acetate (CaAC) is a more effective phosphorus binder than, among other calcium salts, calcium carbonate (CaCO3). More efficient binding allows serum phosphorus to be controlled with a lower dose; moreover, less calcium seems to be absorbed when CaAC is used. These properties could reduce the incidence of hypercalcemia; however, in clinical practice few reports have compared these two calcium salts, and results disagree. We evaluated in a 24-week prospective crossover study the clinical efficiency of CaCO3 and CaAC in 10 selected chronic hemodialysis patients. Only 7 patients completed the study period. The patients were randomly assigned to start treatment with one of the two calcium salts; after 12 weeks they shifted to the other treatment. Serum analytical tests included weekly control of calcium, phosphorus, and alkaline phosphatase. PTH values (intact molecule) were obtained initially and at the end of every study period. The same good control of the phosphorus level (4.79 ± 0.6 vs. 4.94 ± 0.8 mg/dl) was obtained with CaAC (mean doses 4.1 ± 0.3 g/day) as with CaCO3 (mean doses 4.01 ± 0.8 g/day). The mean serum calcium levels were similar (10.36 ± 0.5 vs. 10.20 ± 0.5 mg/dl). The dose of elemental calcium administered was significantly less with CaAC (957 ± 83 mg/day) than with CaCO3 11 mg/dl) was similar during the two treatment periods (13% with CaAC vs. 14% with CaCO3 65 was comparable (9.5 vs. 11.9%). In conclusion: 40% less calcium needs to be supplied when CaAC is used; however, the control of hyperphosphatemia and the frequency of hypercalcemia was the same as with CaCO3. There is no clear advantage of CaAC over CaCO3 in a medium-length (24 weeks) comparativ

ISSN:0250-8095    

DOI:10.1159/000168713

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

Ultramorphological images and details of an uremic echinocyte are shown. The images confirm the existence of uremic echinocytes and demonstrate that atomic force microscopy can provide high-resolution images of cell surfaces.

ISSN:0250-8095    

DOI:10.1159/000168714

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

In newly diagnosed insulin-dependent diabetes mellitus, the mechanisms underlying the concomitant occurrence of magnesium deficiency and normal blood magnesium concentration are unknown. The renal handling of magnesium was, therefore, studied in 37 children with newly diagnosed insulin-dependent diabetes mellitus and in 13 controls. Circulating magnesium levels were similar in patients and controls (0.86 vs. 0.84 mmol/l). However, the urinary excretion of magnesium was significantly higher in patients (90.6 vs. 32.2 µmol/l GFR). In the patients a significant positive correlation was found between excretion of magnesium and glycosuria or blood hydrogen ion activity. It is concluded that osmotic diuresis and acidosis increase magnesium excretion in newly diagnosed diabetes mellitus

ISSN:0250-8095    

DOI:10.1159/000168715

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

In uremia there is a marked elevation of serum levels of indoxyl sulfate due to its decreased renal clearance. Indoxyl sulfate is synthesized in the liver from indole which is produced by bacteria in the intestines. To determine the role of indoxyl sulfate in the progression of chronic renal failure, we administered indole, the precursor of indoxyl sulfate, to subtotally nephrectomized uremic rats. The oral administration of indole increased the serum levels of creatinine and blood urea nitrogen and decreased creatinine, inulin, and p-aminohippuric acid clearances. The glomerular sclerosis index in the indole-treated rats was higher than in the control uremic rats. After oral administration, indole could not be detected in the urine, but large amounts of its metabolite, indoxyl sulfate. Thus, indole administration stimulated glomerular sclerosis in a uremic model through the production of indoxyl sulfate.

ISSN:0250-8095    

DOI:10.1159/000168716

出版商:S. Karger AG    

年代:1994

数据来源: Karger