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Manuel Pascual

Publications and source records attributed to Manuel Pascual.

34 records · Page 2Linked to original sources
PubMed2004

Hepatitis C, acute humoral rejection, and renal allograft survival.

The effect of recipient hepatitis C virus (HCV) infection on renal allograft loss and acute rejection in kidney transplantation remains controversial. We studied 354 renal allograft recipients transplanted during 1996 to 2001 who had HCV antibodies (Ab) measured before transplantation. The primary outcome was death-censored allograft loss and the secondary outcome was acute humoral rejection (AHR). Compared with HCV Ab-negative patients, those with positive HCV Ab had longer time on dialysis before transplantation, higher percentage of panel-reactive antibodies (PRA), were more likely to receive a cadaveric transplant, and were more likely to develop delayed graft function (DGF). In univariate analyses, predictors of renal allograft loss included HCV, cadaveric graft, PRA >20%, HLA mismatch > or =5, retransplantation, DGF, induction therapy, and AHR. When adjusted for PRA >20%, HLA mismatch > or =5, and multiple transplant status, HCV was not a statistically significant predictor of allograft loss. HCV was also associated with AHR but lost significance when adjusted for PRA >20%. HCV Ab-positive patients were more likely to have longer duration of dialysis before transplantation prior to kidney transplants, higher PRA, and to receive cadaveric transplants. These characteristics likely resulted in more DGF and AHR after transplantation. After adjusting for these confounding factors, the association between HCV Ab positivity and renal allograft loss was notably attenuated and no longer statistically significant.

Adult↗
PubMed2004

Analysis of the cardiovascular risk profile in stable kidney transplant recipients after 50% cyclosporine reduction.

BACKGROUND: Long-term use of cyclosporine (CsA) contributes to post-transplant cardiovascular disease (CVD). Hence, a reduction in CsA dosage in kidney transplant recipients (KTR) may improve long-term outcomes. We analyzed the effects of 50% CsA dose reduction on the CVD risk profile in stable KTR. METHOD: Thirty-one KTR on a regimen of CsA, prednisone and mycophenolate mofetil (MMF) were studied. Patients were randomized to either a) continue their previously determined CsA dose (control group, n = 15) or b) lower their CsA dose by 50% (CsA reduction group, n = 16). Renal function, blood pressure, lipid profile, plasma homocysteine (HCY), C-reactive protein (CRP), fibrinogen, and uric acid were compared at baseline and at 6 months. RESULTS: At 6 months, there was a significant improvement in allograft function, systolic blood pressure, number of anti-hypertensive medications and serum uric acid levels in the CsA reduction group. No significant decrease in plasma HCY, CRP, fibrinogen or improvement in lipid profile was found. In contrast, in the Control group, there was a significant increase in HCY, uric acid, and triglycerides. No acute rejection occurred in either group. CONCLUSIONS: A greater reduction in CsA dose could further improve CVD risk profiles, although this may increase the risk of acute or subclinical rejection.

Adult↗
PubMed2004

Interferon-alpha therapy in liver transplant recipients: lack of association with increased production of anti-HLA antibodies.

Interferon-alpha (IFN) is a useful treatment for active HCV infection. In kidney transplantation, IFN has been shown to trigger acute rejection with de novo anti-HLA antibodies. Interferon-alpha has not been reported to enhance the risk of acute rejection in HCV-positive liver transplant recipients (LTRs). Sera were collected from 44 LTRs greater than 6 months post-transplant. Sera were tested with ELISA for the presence and the specificity of anti-HLA antibodies. The prevalence of anti-HLA antibodies was 11% and was not significantly different in 13 HCV-positive recipients who received IFN, compared with 10 who did not receive IFN (8% vs. 20%), or with 21 HCV-negative recipients (10%). None of the patients had an acute rejection after starting IFN. In this study, LTRs receiving IFN did not have an increased frequency of anti-HLA antibodies. This may partially explain the safety of IFN previously reported in LTRs requiring antiviral therapy.

Antibodies↗
PubMed2004

[Preoperative assessment in emergency cardiovascular surgery].

In the emergency situation, preoperative patient work-up for cardio-vascular surgery is quite different from the elective setting. We have analyzed a consecutive series of 5576 cases out of which 823 underwent emergency procedures (14.8%). The most frequent problems requiring emergent intervention were peripheral vascular (186 cases; 22.6% of the emergent procedure), followed by coronary artery disease (156 cases; 19.0%), thoracic aortic aneurysms (86 cases; 10.4%), abdominal aortic aneurysms (54 cases; 6.6%), congenital heart disease (36 cases: 4.4%), heart and heart lung transplantation (31 cases; 3.8%), problems with cardiac rythm (25 cases: 3.0%), and others (267 cases: 32.4%). Classification by proportion of urgent procedures with reference to elective operations shows a different picture. As a matter of fact transplantations were always emergency procedures (100%), whereas repair of aortic dissections type A and B was an emergency procedure in 81.5%. Emergency thoracic and abdominal aortic aneurysm repair accounted for 30% and 20% respectively and the corresponding proportion for peripheral vascular surgery is 19%. However, emergency surgery for acute coronary ischemia, valvular and congenital heart disease accounted for somewhat less than 10% for each group of these pathologies. Systematic pre-operative diagnostic work-up is a recognized tool for procedure related risk assessment and superior management of diseases. However, hemodynamic instability and other time related events correlated with negative outcome, are the main driving forces for accelerated diagnostic pathways

Aortic Dissection↗
PubMed2003

A prospective, randomized clinical trial of cyclosporine reduction in stable patients greater than 12 months after renal transplantation.

BACKGROUND: For stable kidney-transplant recipients receiving triple drug therapy with cyclosporine (CsA), prednisone, and mycophenolate mofetil (MMF), it remains unclear what is the optimal dose of CsA beyond the first 6 to 12 months after transplantation. Complete CsA withdrawal has been associated with a significant incidence of acute rejection and, in some studies, chronic rejection as well. METHODS: We performed an open, prospectively randomized, controlled clinical trial to determine whether CsA could be safely reduced by 50%. At 1 year or more posttransplant, 64 patients were randomized to either continue their stable-maintenance CsA dose (control group, n=32) or to lower their CsA dose by 50% over a 2 month period (CsA reduction group, n=32). All patients had stable renal-allograft function at the time of enrollment. RESULTS: Within 6 months of randomization, no episode of acute rejection or graft loss occurred in either group. Patients in the CsA reduction group had a slight but significant increase in their glomerular filtration rate and a trend towards lower serum creatinine. There was also a significant decrease in mean systolic blood pressure, triglycerides, and serum uric acid levels in the CsA reduction group. No significant changes in any of these parameters were observed in the control group. CONCLUSIONS: This study suggests that a strategy consisting of a 50% CsA reduction is safe and is not associated with the increased risk of acute rejection observed in CsA withdrawal studies. It also has the potential to improve short-term allograft function and appears to reduce cardiovascular risk factors such as hypertension and hyperlipidemia.

Adult↗
PubMed2003

Recurrent allograft HCV presenting as acute cellular rejection: successful management with interferon and ribavirin alone.

Hepatitis C virus (HCV) is currently the leading indication worldwide for orthotopic liver transplantation. However, the majority of patients receiving transplant for HCV eventually develop histopathologic evidence of recurrent allograft HCV and approximately 10% die or require retransplantation within the first 5 post-operative years because of accelerated graft injury and cirrhosis. Traditional induction immunosuppressive regimens and intensive immunosuppression used to treat episodes of acute cellular rejection (ACR) are associated with enhanced viral replication and higher likelihood and severity of recurrent HCV. At our institution, therefore, we have used low-dose steroid therapy in an effort to limit HCV replication. However, this practice has been associated with frequent early presentations consistent with ACR. Here, we present three cases consistent with histologic ACR treated with conventional antirejection therapy that improved transiently, but evolved rapidly to progressive HCV. A fourth patient with a similar presentation experienced dramatic improvement in aminotransferases when treated solely with interferon and ribavirin. We propose that histologic characteristics traditionally associated with ACR may, in fact, represent early recurrent HCV as both processes share common immunopathogenetic mechanisms, or alternatively, that both ACR and recurrent HCV may be present simultaneously. We conclude that in cases suggestive of ACR, careful consideration should be given to treatment for recurrent HCV in lieu of or in concert with intensive immunosuppression.

Acute Disease↗
PubMed2003

Acute humoral rejection in hepatitis C-infected renal transplant recipients receiving antiviral therapy.

The use of interferon-alpha (IFN) in hepatitis C (HCV)-infected renal recipients has been associated with acute rejection and graft loss. We reviewed our recent experience in HCV (+) renal recipients treated with antiviral therapy for biopsy proven chronic hepatitis C. Twelve HCV (+) recipients who recently received antiviral therapy were analyzed. Post-treatment sera were tested for donor-specific human leukocyte antigen (HLA) antibodies (DSA). Within 6 months of initiating antiviral therapy, two of 12 patients (17%) developed acute rejection, which was characterized as acute humoral rejection (de novo DSA in serum and C4d deposits in peritubular capillaries). Both progressed to graft failure. Nine of the remaining 10 patients tested did not have DSA. The use of IFN was associated with severe acute humoral rejection (C4d +, DSA +). The recognition of IFN-associated acute humoral rejection in this series may explain the high rate of graft loss reported previously in renal recipients receiving IFN.

Adult↗
PubMed2002

Prevalence of renal cell carcinoma in patients with ESRD pre-transplantation: a pathologic analysis.

BACKGROUND: Acquired renal cystic disease (ARCD), renal adenoma (AD), and renal cell carcinoma (RCC) are more common in patients with end-stage renal disease (ESRD). However, the prevalence of these conditions in patients undergoing transplantation, and the clinical characteristics associated with their occurrence are unclear. METHODS: At our institution, the majority of patients undergo an ipsilateral native nephrectomy at the time of transplantation, providing a unique opportunity to study the prevalence and pathology of ARCD, AD and RCC in ESRD. We retrospectively reviewed all consecutive nephrectomy pathology reports over a six year period. Demographic and clinical characteristics associated with these lesions were identified. RESULTS: Two hundred and sixty nephrectomy reports were reviewed: ARCD, AD, RCC and oncocytoma were found in 33%, 14%, 4.2% and 0.6% of cases, respectively. On multivariable analysis, ARCD was positively associated with male sex and longer dialysis duration and negatively associated with peritoneal dialysis. Similarly, AD was positively associated with male sex, longer dialysis duration and greater age. There was a trend for RCC cases to share similar associations although the small total number of cases precluded findings of statistical significance. CONCLUSION: By pathologic analysis, renal tumors are more common in the pre-transplant ESRD population than previously reported (using radiologic methods). Our study also identifies risk factors for their occurrence. This may prove useful in designing screening studies for renal tumors in this patient population.

Adenoma↗
PubMed2001

Chronic humoral rejection: identification of antibody-mediated chronic renal allograft rejection by C4d deposits in peritubular capillaries.

The pathogenesis of chronic renal allograft rejection (CR) remains obscure. The hypothesis that a subset of CR is mediated by antidonor antibody was tested by determining whether C4d is deposited in peritubular capillaries (PTC) and whether it correlates with circulating antidonor antibodies. All cases (from January 1, 1990, to July 31, 1999) that met histologic criteria for CR and had frozen tissue (28 biopsies, 10 nephrectomies) were included. Controls were renal allograft biopsies with chronic cyclosporine toxicity (n = 21) or nonspecific interstitial fibrosis (n = 10), and native kidneys with end-stage renal disease (n = 10) or chronic interstitial fibrosis (n = 5). Frozen sections were stained by two-color immunofluorescence for C4d, type IV collagen and Ulex europaeus agglutinin I. Antidonor HLA antibody was sought by panel-reactive antibody analysis and/or donor cross matching in sera within 7 wk of biopsy. Overall, 23 of 38 CR cases (61%) had PTC staining for C4d, compared with 1 of 46 (2%) of controls (P < 0.001). C4d in PTC was localized at the interface of endothelium and basement membrane. Most of the C4d-positive CR tested had antidonor HLA antibody (15 of 17; 88%); none of the C4d-negative CR tested (0 of 8) had antidonor antibody (P < 0.0002). The histology of C4d-positive CR was similar to C4d-negative CR, and 1-yr graft survival rates were 62% and 25%, respectively (P = 0.05). Since August 1998, five of six C4d-positive CR cases have been treated with mycophenolate mofetil +/- tacrolimus with a 100% 1-yr graft survival, versus 40% before August 1998 (P < 0.03). These data support the hypothesis that a substantial fraction of CR is mediated by antibody (immunologically active). C4d can be used to separate this group of CR from the nonspecific category of chronic allograft nephropathy and may have the potential to guide successful therapeutic intervention.

Adult↗
PubMedDate not supplied

[De novo inflammatory bowel diseases after liver transplantation: description of four new cases and a review of the literature].

Inflammatory bowel diseases are a result of an aberrant mucosal immune response to gut microflora. Several groups have reported newly diagnosed inflammatory bowel diseases following solid organ transplantation and subsequent immunosuppressive therapy. We describe four cases of newly diagnosed inflammatory bowel diseases following liver transplantation in a pool of 120 transplanted patients. These patients had no prior history of inflammatory bowel diseases or primary sclerosing cholangitis and were immunosuppressed. Two patients were transplanted for a hepatitis C related cirrhosis, one for alcoholic cirrhosis and one patient for autoimmune cirrhosis. Three patients were diagnosed with ulcerative colitis and one with Crohn's disease. These four patients were on a cyclosporin monotherapy when their inflammatory bowel diseases were diagnosed. These data suggest that cyclosporin monotherapy following solid organ transplantation does not prevent development of inflammatory bowel diseases.

Adult↗