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131.
E. Stermer J. Bejar† I. Miselevich† O. Goldstein D. Keren A. Lavy J. H. Boss† D. Keren 《Colorectal disease》2005,7(4):345-349
BACKGROUND: Total excision of colonic polyps is not always attainable and in some patients it is clinically contraindicated. Also, a resected polyp may be lost at any step between its endoscopic removal and its embedding in paraffin. The aim of this study was to compare the histological features of colonic polyps as analysed by the study of biopsy-forceps obtained samples with those assessed on scrutinizing the totally resected growths. PATIENTS AND METHODS: This prospective study included a cohort of 59 patients in whom, in the course of an elective colonoscopy, a total excision of a 6 mm-sized or larger polyp was called for. Sizeable biopsies were obtained by means of an Olympus Multibyte forceps prior to the total polypectomy. Subsequent to the study of the polypectomy specimens, the forceps biopsy samples were submitted for histological examination. The pathologists were blinded as to the source of the tissue they were studying. The diagnoses rendered by evaluating the biopsy samples and polypectomy specimens of each patient were contrasted with each other. RESULTS: Major discrepancies between the histological features of the fragments captured by the biopsy-forceps and the factual nature of the totally removed polyps were uncovered in 11 (18.6%) of 59 cases. Intriguingly, the grade of the tumours was underrated in all the 11 cases, as judged by contrasting the tentative diagnoses of the forceps-biopsies with the decisive diagnoses of the polypectomies. Importantly, 2 adenocarcinomas would have been missed by just looking at the forceps-retrieved sample. CONCLUSIONS: In our experience, a discordance of 18.6% is to be expected between the diagnoses rendered after examining forceps-biopsies of and totally excised colonic polyps. Nevertheless, it is advisable to procure biopsies prior to the excision of the growths, because on those occasions in which patients' growths cannot be removed or have not been retrieved for one reason or another, a small forceps-captured tissue sample correctly reflects the characteristics of the polyp in 81.4% of the cases. Finally, the biopsies may be discarded in the event that total removal was successful. 相似文献
132.
133.
Yukiko Hasuike Takeshi Nakanishi Rintarou Moriguchi Yoshinaga Otaki Masayoshi Nanami Yasue Hama Miki Naka Koji Miyagawa Masaaki Izumi Yoshihiro Takamitsu 《Nephrology, dialysis, transplantation》2004,19(6):1474-1479
BACKGROUND: Cyanide is a toxic agent, and its detoxification product, thiocyanate, may be a major pathogenetic substance in uraemia. Recent studies examining the myeloperoxidase(MPO)/thiocyanate system have suggested a link between thiocyanate and atherosclerosis. However, inaccuracies in conventional assays for cyanide and thiocyanate have limited the understanding of their metabolism in haemodialysis (HD) patients. METHODS: We used high-performance liquid chromatography to measure cyanide in erythrocytes and thiocyanate in plasma in 43 HD patients and in a group of 46 healthy controls that included 15 current smokers. To clarify the metabolic conversion of cyanide to thiocyanate in uraemic patients, we also measured cysteine and sulfate. We then used stepwise regression analysis to analyse factors that determine erythrocyte cyanide and plasma thiocyanate. RESULTS: Mean cyanide and thiocyanate were significantly greater in HD patients than in non-smoking controls. However, cyanide was far below lethal concentrations in dialysis patients. Thiocyanate was six to seven times greater in HD patients than in non-smoking controls, and decreases in thiocyanate following dialysis were only 19.3+/-3.5%. Multiple regression analysis showed a positive correlation between cyanide and thiocyanate in controls, but a negative correlation in HD patients. In patients, an inverse relationship between thiocyanate and BUN was also observed. CONCLUSIONS: The elevation of thiocyanate in patients undergoing dialysis probably is secondary to both limited efficiency of HD and deranged metabolism of cyanide and thiocyanate. Because thiocyanate is a preferred substrate for MPO, it may play a role in uraemic complications including cardiovascular events. 相似文献
134.
Y Namba T Moriyama M Kyo K Oka Y Kokado Y Shi R Imamura N Ichimaru A Okuyama S Takahara 《Clinical transplantation》2004,18(S11):29-33
Abstract: Angiotensin-converting enzyme inhibitor (ACEI) has become recognized as agents that have renoprotective effects in the treatment of progressive renal diseases including post-transplant kidneys. Previously we demonstrated the safety and effectiveness of ACEI treatment on the hypertensive proteinuric post-transplant patients ( N = 10) who had been followed up for 12 months. However, not all patients show good response in urinary protein reduction. We aimed to analyse the histopathological factor(s) affecting the responsiveness of proteinuria to ACEI treatment. Fourteen post-transplant patients with proteinuria who were treated with ACEI and underwent allograft biopsy were analysed. Eight patients showed 50% or more reduction in proteinuria (responder). The other 6 patients showed less (< 50%) reduction in proteinuria (non-responder). There was no difference in clinical characteristics (BP, renal function, donor age, recipient body mass index), dietary sodium or protein intake, and diuretic use between the two groups. As a histopathological characteristic, glomerular size in responder group was significantly larger than that in non-responder group. This suggests that the large glomerular size at least partly contributes to the responsiveness in urinary protein reduction to ACEI treatment in kidney allograft recipients with proteinuria. 相似文献
135.
Gabriel Mircescu Dimitrie Capsa Maria Covic Mirela Gherman Caprioara Gheorghe Gluhovschi Ovidiu Golea Nicolae Ursea Liliana Garneata Vasile Cepoi Nicolae Constantinovici Adrian Covic 《Nephrology, dialysis, transplantation》2004,19(12):2971-2980
INTRODUCTION. This report describes the current status of nephrology and renal replacement therapy (RRT) in Romania, a country with previously limited facilities, highlighting national changes in the European context. METHODS: Trends in RRT development were analysed in 2003, on a national basis, using the same questionnaires as in previous surveys (1991, 1995). Survival data and prognostic risk factors were calculated retrospectively from a large representative sample of 2284 patients starting RRT between January 1, 1995 and December 31, 2001 (44% of the total RRT population investigated). RESULTS: In 2003, RRT incidence [128 per million population (p.m.p.)] and prevalence (250 p.m.p.) were six and five times higher, respectively, than in 1995. The annual rate of increase in the stock of RRT patients (11%) was supported mainly by an exponential development of the continuous ambulatory peritoneal dialysis (CAPD) population (+600%), while the haemodialysis (HD) growth rate was stable (+33%) and renal transplantation made a marginal contribution. Renal care infrastructure followed the same trend: nephrology departments (+100%) and nephrologists (+205%). The characteristics of RRT incident patients changed accordingly to current European epidemiology (increasing age and prevalence of diabetes and nephroangiosclerosis). The estimated overall survival of RRT patients in Romania was 90.6% at 1 year [confidence interval (CI) 89.4-91.8] and 62.2% at 5 years (CI 59.4-65.0). Patients' survival was negatively influenced (Cox regression analysis) by age >65 years (P < 0.001), lack of pre-dialysis monitoring by a nephrologist [P = 0.01, hazards ratio (HR) = 0.8], severe anaemia, lack of erythropoetin treatment (P < 0.001, HR = 0.6), and co-morbidity, e.g. cardiovascular diseases (P < 0.001, HR = 1.8) and diabetes mellitus (P < 0.001, HR = 2.2). CONCLUSIONS: Although the rate of increase in RRT patient stock in 1996-2003 in Romania was the highest in Europe, the prevalence remained below the European mean. As CAPD had the greatest expansion, followed by HD, an effective transplantation programme must be set up to overcome the imbalance. The quality of RRT appears to be good and survival was similar to that in other registries. Further evolution implies strategies of prevention, based on national surveys, supported by the Romanian Renal Registry. 相似文献
136.
Clinicopathological study of vesicoureteral reflux (VUR)-associated pyelonephritis in renal transplantation 总被引:1,自引:0,他引:1
K Ohba M Matsuo M Noguchi M Nishikido S Koga H Kanetake A Nazneen D Liu M S Razzaque T Taguchi 《Clinical transplantation》2004,18(S11):34-38
Abstract: We retrospectively studied the occurrence of vesicoureteral reflux (VUR)-associated pyelonephritis using renal biopsies obtained from the transplanted kidneys, and correlated the histological changes with clinical parameters. Out of a total of 131 renal biopsies performed between 1990 and 2001 on renal transplant patients at the department of Urology of Nagasaki University Graduate School of Biomedical Sciences, 12 patients showed pyuria more than twice in a single year. Seven of these 12 patients were available for determining VUR by voiding cystourethrography (VCUG). Cystoureterography demonstrated VUR in three of seven studied patients with pyuria. A histopathological examination revealed dilatation of both proximal and distal tubules in renal biopsies of transplant patients with VUR, compared to renal biopsies of transplant patients without VUR, or non-transplanted patients with thin membrane disease. One of the patients with VUR showed advanced features of chronic pyelonephritis in four consecutive biopsies at different time points, suggesting a late stage of reflux nephropathy in the transplanted kidney. We conclude from our study that the occurrence of VUR-related pyelonephritis may be one of the important long-term complications in the survival of renal allografts. 相似文献
137.
138.
Early assessment of renal resistance index after kidney transplant can help predict long-term renal function. 总被引:6,自引:0,他引:6
Angelo Saracino Giovanni Santarsia Angela Latorraca Vito Gaudiano 《Nephrology, dialysis, transplantation》2006,21(10):2916-2920
BACKGROUND: Color Doppler ultrasonography of intrarenal arterial resistance index (RI), performed early after kidney transplant, has proven to reliably predict short-term allograft function. The aim of this study was to assess whether it could also predict long-term renal function. METHODS: We retrospectively analysed 76 kidney transplant patients who underwent RI assessment within 1 month after the transplant, subdivided into two groups according to RI values, lower (group A) or higher (group B) than its median value (0.635). RESULTS: Compared with group A subjects, the patients of group B were older at the time of transplant (42 +/- 9 vs 35 +/- 8 years; P = 0.001), the donor age was also older (41 +/- 16 vs 33 +/- 13 years; P = 0.02) and had a slightly higher proteinuria (0.54 +/- 0.5 vs 0.32 +/- 0.2 g/24 h; P = 0.02). Serum creatinine, ciclosporin or tacrolimus trough level, arterial blood pressure, number of human leukocyte antigen (HLA) mismatches, anti-hypertensive medications and incidence of delayed graft function were not significantly different between the two groups. By univariate analysis, RI turned out to directly correlate with the recipient age, donor age and daily proteinuria (P = 0.007, P = 0.0007 and P = 0.02, respectively). Multivariate analysis showed that only donor and recipient age maintained their independent predictive value on RI. Kaplan-Meier analysis, considering a serum creatinine increase >50% as the endpoint of the study, showed a statistically significant different graft survival in the two groups (log-rank test = 5.489; P = 0.01). The univariate relative risk of deterioration of graft function among patients with higher RI was 3.77. Proteinuria and recipient age increased the risk as well. CONCLUSIONS: Our data seem to suggest that early determination of RI can help predict long-term graft function in kidney transplant recipients. 相似文献
139.
Darren S Parsons David A Reaveley Darrell V Pavitt Madhukar Misra Edwina A Brown 《Nephrology, dialysis, transplantation》2003,18(9):1848-1853
BACKGROUND: Studies have reported an increase in median Lipoprotein (Lp) (a) in patients with high molecular weight (HMW) apolipoprotein (apo) (a) isoforms and renal impairment. Some studies identify Lp (a) levels as a risk factor for vascular disease in renal failure whilst others have demonstrated an association with apo (a) isoform type and vascular disease. METHODS: A total of 239 patients at end-stage renal failure (ESRF) were studied prior to the initiation of dialysis. Blood was taken for Lp (a) levels and apo (a) isoforms. Clinical vascular disease (CVD) was assessed on the basis of clinical history and Rose questionnaire. The control group for Lp (a) levels consisted of 228 healthy volunteers. RESULTS: Despite a higher median Lp (a) level in those with HMW isoforms, 30% of patients had Lp (a) levels <10 mg/dl. Overall, 49% patients were identified as having CVD. Diabetes, smoking history and Lp (a) levels were significantly associated with CVD in logistic regression analysis, although when patients with low molecular weight (LMW) and HMW isoforms were analysed separately, Lp (a) levels were not significantly associated with CVD in those with LMW isoforms. The rates of CVD in those with HMW isoform and low Lp (a) levels were significantly lower than those with HMW isoforms and elevated Lp (a) levels, 34 vs 57% (P < 0.01). CONCLUSIONS: Although median Lp (a) levels in those patients at ESRF with HMW isoforms are higher than controls, in a third of such patients Lp (a) levels remain relatively low. These patients have lower rates of CVD than those with high levels of Lp (a). 相似文献
140.
中药灌肠治疗慢性肾功能不全的近期疗效观察 总被引:1,自引:0,他引:1
目的探讨以生大黄为主的中药保留灌肠治疗慢性肾功能不全的确切疗效。方法对324例临床确诊为慢性肾功能不全的患者,在内科保守治疗的基础上加用以生大黄为主的中药保留灌肠,每晚1次,4周为1疗程,通过观察治疗前后肾功能的变化评价疗效。结果疗程结束后,氨质血症及尿毒症早期患者的BUN、Ser较治疗前明显降低(P<0.05),胃肠道症状明显改善。对终末期尿毒症患者的临床症状及肾功能指标改善不明显。结论以生大黄为主的中药保留灌肠对氨质血症及尿毒症早期疗效肯定,对终末期尿毒症病人疗效不佳。 相似文献