Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0022116 (ischemia)
 91,303 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To avoid the center effect and the possible hidden interactions of multicenter studies, the validity of the Cox Proportional Hazards Model for the analysis of a single-center kidney transplant program was tested, considering 287 renal transplants performed in a 10-year period. The inclusion of type of donor and main immunosuppressive drug as covariates in the model did not violate the proportionality assumption of the Cox model. According to this method, the following covariates were significant in predicting graft survival: cyclosporine, type of donor, good human leukocyte antigen (HLA)-A and HLA-B match (DR data were not considered), highest percentage of reactive antibodies against panel cells, and nephroangiosclerosis as a primary renal disease. Cyclosporine did not significantly improve graft survival in living related donor transplants. Pretransplant blood transfusions, cold ischemia time, and donor ABO blood group were initially significant but dropped out in the step-down procedure. Recipient's age at transplant, cyclosporine, HLA-A and HLA-B match, and nephroangiosclerosis were significant in predicting patient survival. It was concluded that using long-term data of cadaveric and living related renal transplants either on azathioprine or cyclosporine is a valid way to perform multivariate analysis of single-center transplant programs that do not have large samples.
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PMID:An alternative approach for statistical analysis of kidney transplant data: multivariate analysis of single-center experience. 305 83

Long-term survival statistics for organ allografts have not improved substantially over time, despite improved immunosuppression and organ preservation and better surgical and perioperative management. Chronic rejection is the most important long-term limitation in allografts and increasingly seems to be caused by a multifactorial series of antigen-dependent and antigen-independent factors. Early injury is critical to late events, whether antigen driven (early acute rejection episodes and human leukocyte antigen mismatching) or antigen independent (ischemia/reperfusion injury and brain death). Ongoing alloimmunologic injury to the host and inadequate organ mass functioning (donor age, gender, race, and organ size) also seem to be important to this persisting process. Associated recipient conditions, which includes hypertension and hyperlipidemia, and postoperative complications, which include drug nephrotoxicity and infections, may affect this late-phase graft loss. These deleterious risk factors for chronic rejection of long-functioning allografts are an important subject for future investigation.
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PMID:Chronic allograft failure: the clinical problem. 914 41

The impact of matching for the human leukocyte antigen (HLA)-DQ phenotype in cadaveric renal transplantation is unclear. We analyzed the effect of matching serologically defined HLA-DQ phenotypes on renal allograft survival in 12,050 first cadaveric renal transplants (recipients were 63.5% white and 36.5% African-American). Recipients were entered into the South-Eastern Organ Procurement Foundation (SEOPF) database between 1 October 1987 and 6 June 1995. A series of life table analyses were done to test the equality of survival curves for HLA-DQ match, both alone and accommodating for differences in recipient race and HLA-DR match. Cox regression models were then performed to detect differences in allograft survival based upon HLA-DQ match. Initial adjustments were done by recipient race. Subsequent adjustments were done by recipient and donor race, age and sex, cold ischemia time (CIT), body mass index (BMI), cyclosporine A (CyA) use, peak panel reactive antibody (PRA) titer, year of transplant, presence of diabetes mellitus (DM), and degree of HLA-A,B and HLA-DR match as covariates. The effect of varying degrees of HLA-DQ match on graft survival were similar between the two races (p = 0.87). In all recipients, an 8.3% reduction in graft failure was observed for each increase in HLA-DQ match using the Cox regression model adjusted only for recipient race (p = 0.004). A non-significant 3.0% reduction in graft failure (p = 0.38) was observed for each level of increasing HLA-DQ match when using the Cox regression model adjusted for recipient and donor race, age and sex, CIT, BMI, CyA use, year of transplant, DM, HLA-A,B and -DR match. In this model, superior HLA-A,B match and HLA-DR match, recipient and donor age, male donor sex, shorter CIT, white race of recipient, lower peak PRA, CyA use, and absence of DM significantly improved graft survival (all < or = 0.004). We conclude that HLA-DQ matching does not significantly affect cadaveric renal allograft survival once adjusted for other known predictors of graft outcome.
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PMID:HLA-DQ matching in cadaveric renal transplantation. 936 45

Live donor renal transplantation has many advantages including greater graft and patient survival, shorter waiting periods, improved human leukocyte antigen matching, and less cold ischemia. Until recently, disincentives from the operation, such as prolonged hospitalization, postoperative pain, and significant convalescence, have deterred live donor renal transplantation. This article describes the technique of laparoscopic live donor nephrectomy and briefly reports the results. The procedure has resulted in improved postoperative recovery and shorter convalescence, with no effect on recipient renal function.
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PMID:Laparoscopic live donor nephrectomy. 1008 64

Long-term prognosis in kidney transplant recipients depends on multiple factors. The purpose of this study was to quantify the influence of hyperuricemia and hyperglycemia (elements of the so-called 'syndrome X', i.e., a combination of metabolic disorders like hyperuricemia, diabetes mellitus, hyperlipidemia, and hypertension) on organ function in 350 kidney transplant recipients who had received 375 kidney transplants up to 1990 and in whom sex, age of recipient and donor, nephrologic disease, duration of dialysis, human leukocyte antigen (HLA) classification, and duration of transplant ischemia had been well matched. We found the influence of hyperuricemia on graft survival to be statistically significant (p < or = 0.05), while a statistically significant correlation between hyperglycemia and graft survival could not be detected in the present study. The transplant survival rates 2, 4, and 5 yr post-kidney-transplantation were 96.7, 80.7, and 78.7 in normogylcemic patients vs. 96.9, 85, and 82.7% in hyperglycemic ( > 100 mg,dL) kidney transplant recipients (p > 0.05). Transplant survival in hyperuricemic patients (male, > 8 mg dL; female, > 6.2 mg/dL) 2, 4, and 5 yr post-transplantation was significantly reduced (92.2, 70.6, and 68.8% vs. 98.1, 85.6, and 83.3%), as compared to normouricemic recipients. A combined presence of both hyperuricemia and hyperglycemia probably influencing the prognosis post-kidney-transplantation failed to reach the level of statistical significance. We found a significant correlation between age of recipients and plasma glucose (p < or = 0.01) and between serum uric acid concentrations and diuretic therapy (p < or = 0.05) and gender (p < or = 0.(5). In conclusion, hyperuricemia after kidney transplantation seems to reduce graft survival, whereas an influence of the carbohydrate metabolism has to be denied.
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PMID:Influence of hyperglycemia and hyperuricemia on long-term transplant survival in kidney transplant recipients. 1051 17

While the relevance of pre-formed anti-human leukocyte antigen (HLA) antibodies has been studied extensively, the role of anti-HLA class I and II antibodies produced after cadaveric kidney transplantation is still a matter of discussion. As it has been proposed that they are involved in a considerable number of cases, it should be investigated whether a post-transplant monitoring is a sensitive parameter for the early diagnosis of acute rejection episodes. Additionally, it has been suggested that antibodies are a major cause for chronic rejection; thus, it would be of interest to correlate antibody detection and graft survival. We retrospectively investigated 59 patients after a first cadaveric kidney transplantation without known anti-HLA antibodies (complement-dependent cytotoxicity [CDC] testing). The panel reactivity was determined with a new highly sensitive and specific flow-cytometric technique (Flow-PRA Screening Test, One Lambda, Canoga Park, USA) in sequentially collected serum samples pre- and post-transplant. In patients with acute rejection episodes during the clinical course, the last sample prior to rejection, and in patients without rejection, the last sample prior to discharge, was analyzed. Furthermore, we analyzed 3-yr graft survival and several clinical parameters such as cold ischemia time (CIT). Twenty-four of 59 patients (41%) experienced acute rejections during the clinical course. Five of 59 died with a functioning graft within the first 3 yr. Seven of 54 patients, still alive after 3 yr, lost their graft. Anti-HLA antibodies were detectable in only 7/59 patients and a correlation between antibody positivity and acute rejections (p = 0.32 and 0.54 for anti-HLA class I and II, respectively) could not be identified (sensitivity 12.5 and 8.3%). However, we found a significant correlation between the detection of anti-HLA class II and graft loss within 3 yr (p = 0.005, specificity 97.9%). Additionally, anti-HLA class II positive patients had significantly longer CIT (p = 0.003). Whether the detection of anti-HLA class II antibodies in the early post-transplant phase is of great value for the identification of patients at high risk for early graft loss needs additional investigation. However, we found that anti-HLA antibodies are detectable only in a minority of unsensitized patients and we conclude that flow-cytometric monitoring with Flow PRA is not a sensitive parameter for the early diagnosis of acute rejection episodes in patients after first cadaveric kidney transplantation.
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PMID:Monitoring of anti-HLA class I and II antibodies by flow cytometry in patients after first cadaveric kidney transplantation. 1069 42

The advent of small bowel transplantation has provided selected patients with chronic intestinal irreversible failure with a physiologic alternative to total parenteral nutrition. Recently a standardized technique for living related small bowel transplantation (LR-SBTx) has been developed. Three patients with short bowel syndrome underwent LR-SBTx at our institution. All donors were ABO compatible with a good human leukocyte antigen match. A segment of 180 to 200 cm of ileum was harvested and transplanted with its vascular pedicle constituted by the ileocolic artery and vein. The grafts were transplanted with a short cold and warm ischemia time. The immunosuppression regimen consisted of oral FK-506, prednisone, and intravenous induction with atgam. Serial biopsies of the intestinal grafts were performed to evaluate rejection or viral infections. The postoperative course was uneventful for all donors. All of the recipients are currently alive and well. Two of three patients are off total parenteral nutrition and tolerating an oral diet with no limitations on daily activity. In the third patient, the graft was removed 6 weeks after transplantation. At the time of enterectomy, no technical or immunologic complications were documented. Absorption tests for D-xylose and fecal fat studies were performed showing functional adaptation of the segmental graft. All biopsies were negative for acute rejection. A well-matched segmental ileal graft from a living donor can provide complete rehabilitation for patients with short bowel syndrome. Our initial experience suggests that the risk of acute rejection and infection is greatly reduced compared to cadaveric bowel transplantation. Further clinical application of this procedure is warranted.
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PMID:Segmental living related small bowel transplantation in adults. 1133 80

Eales disease, first described by Henry Eales in 1880, remains an enigma. The disease, observed more commonly in the Indian subcontinent than in the rest of the world, occurs in young healthy adult males, initially presenting as retinal periphlebitis and later as retinal ischemia that may lead to vascular alterations and neovascularization. Recurrent vitreous hemorrhage with or without retinal detachment is the common sequelae. In recent years, immunological, molecular biological, and biochemical studies have indicated the role of human leukocyte antigen, retinal autoimmunity, mycobacterium tuberculosis genome, and free radical mediated damage in the etiopathogenesis of this disease. However, its etiology appears to be multifactorial. The management depends on the stage of the disease and consists of medical treatment with oral corticosteroids in the active inflammatory stage and laser photocoagulation in the advanced retinal ischemia and neovascularization stages. The results of vitreoretinal surgery have been found to be satisfactory in case of vitreous hemorrhage with or without retinal detachment.
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PMID:Eales disease--an update. 1205 8

Tacrolimus and cyclosporine in the microemulsion formulation Neoral have demonstrated improvements in acute rejection rates after renal transplantation compared with conventional cyclosporine formulation, Sandimmune. To evaluate whether these drugs are also associated with improvements in chronic allograft failure (CAF) rates, we retrospectively analyzed 32,040 primary renal allograft recipients reported to the United States Renal Data System (USRDS) between 1994 and 1997. Graft loss secondary to CAF was defined as graft loss beyond 6 months post-transplant, censored for death, acute rejection, thrombosis, infections and noncompliance. A Cox proportional hazard model was used to investigate the relationship between graft loss secondary to CAF and the use of conventional cyclosporine formulation, as opposed to cyclosporine microemulsion and tacrolimus (Prograf). The analysis was corrected for confounding variables, such as acute rejection, sex, race, human leukocyte antigen (HLA) mismatch, % panel reactive antibodies (PRA), delayed graft function (DGF), cold ischemia time, induction therapy, dialysis time, etiology of end-stage renal disease, cytomegalovirus (CMV) risk group, donor source, era effect, and mycophenolate mofetil (MMF) use. Cyclosporine microemulsion use was associated with a significantly lower relative risk (RR = 0.6, Cl = 0.5-0.7) for CAF as opposed to conventional cyclosporine formulation. Likewise tacrolimus as compared with conventional cyclosporine formulation was associated with a significantly lower relative risk (RR = 0.7, CI = 0.6-0.8) for CAF. Conventional cyclosporine formulation treatment was associated with a 87.6% adjusted CAF-free survival rate at 4 years. Both tacrolimus and cyclosporine microemulsion were associated with a significantly better adjusted CAF-free survival at 4years (91.4 and 92.4%, respectively). Both cyclosporine microemulsion and tacrolimus are associated with improved graft survival and a decreased relative risk for CAF when compared with the older conventional cyclosporine formulation. This association is independent of the use of MMF or changes in era.
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PMID:Cyclosporine microemulsion and tacrolimus are associated with decreased chronic allograft failure and improved long-term graft survival as compared with sandimmune. 1209 48

The optimal allocation of cadaveric kidneys for transplantation with reference to human leukocyte antigen (HLA) match and sharing these organs to a distant center remains controversial. The current analysis was performed using the United Network for Organ Sharing (UNOS) database for cadaveric kidney transplants (Tx) between 1988 and 1997. The graft survivals of zero-mismatch (matched) kidneys with the mate (mismatched) kidneys were compared. There were 2385 donors and 4770 Tx. Significant differences in recipient demographics between matched and mismatched Tx were: fewer African-American race (AA) in the matched group (9.0% vs. 21.9%), higher number of previous Tx (25.5% vs. 14.8%) and elevated mean cold ischemia time (24.0 vs. 22.2 h). Post-Tx dialysis requirements were similar (22.8% vs. 24.1%, p = 0.62) and matched kidneys had to travel more distance (920 vs. 232 miles). Using a Cox model, the matched group had a decreased relative hazard of graft failure of 23.0% (p = 0.0002) or 35% (p < 0.0001) with and without censoring for death. There was significantly better graft survival in the matched recipients in all pairs except AA (matched) and non-AA (mismatched). For older donors (> or = 50 years, n = 1508), the matched grafts survival was marginally significant (p =0.05). Matched kidneys have improved survival compared with the mismatched kidneys despite the longer distance traveled. The benefit of mismatched transplants was predominantly seen in non-AA.
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PMID:A comparison between recipients receiving matched kidney and those receiving mismatched kidney from the same cadaver donor. 1211 48


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