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P Todeschini

Publications and source records attributed to P Todeschini.

14 recordsLinked to original sources
PubMed1996

ELISA anti-HLA antibody screening identifies non-complement-fixing antibodies responsible for acute graft rejection. A case report.

We report on a kidney transplant recipient experiencing an unexpected early acute vascular graft rejection. Retrospective analysis of patient serum samples, utilizing a new ELISA HLA screening technique, revealed that the rejection crisis and the subsequent graft loss were due to a pretransplant donor-specific pre-sensitization caused by a non-complement-fixing antibody of IgG2 class. The case illustrates the clinical significance of non-complement-fixing anti-HLA antibodies. In addition it is shown that ELISA methods are suitable for detecting potentially harmful donor pre-sensitization in waiting-list patients not detectable by standard lymphocytotoxicity techniques. Hence ELISA could be an alternative to flow cytometry for this purpose. It is concluded that screening and cross-matching techniques which detect non-complement-fixing anti-HLA antibodies could improve graft outcome, and should form part of the immunological monitoring of kidney transplant waiting-list patients.

Adult↗
PubMed1993

Strategies in renal failure and the impact of lipids.

The main points to note in terms of strategies in renal failure and the impact of lipids are: 1) Timing and typing of dyslipidemia; 2) Occurrence of dyslipidemia in the course of strategies (conservative, dialysis and transplantation); 3) How the strategies can handle the impact of lipids. Analysis of point 1 confirms what a complex profile uremic dyslipidemia presents, involving the type, class, composition and enzyme systems involved in lipid metabolism. In conservative and dialysis, type IV (triglycerides) predominates; in transplantation, type II (cholesterol). Examination of point 2 shows the non obligatory relationship between dyslipidemia and the various strategies of treatment. Lipid abnormalities, type IV or II, occur in 50-60% of patients. Uremic factors for dyslipidemia include: 1) enhanced hepatic stimulation or altered removal in conservative strategies; 2) the same causes plus "specific" promotors in dialysis (dialysis fluid, plasticizer leaching; bioincompatibility, etc.); 3) steroid therapy and other "accessories" in transplantation. A genetic predisposition is very likely present in all patients. Point 3, finally, analyzes the various "supplements" that each strategy requires to cope with the lipid impact. Generic rules (ranging from doing nothing, to diet, drugs, etc.) are of value in all strategies when dyslipidemia occurs. More specific rules include: a) Conservative strategies: appropriate dietetic optimization and modulation (protein-lipid-carbohydrate ratio in terms of calories); b) Dialysis: timing treatment and improving biocompatibility; c) Transplantation: reducing steroids as much as possible.

Humans↗
PubMed1992

Flow cytometry evaluation of urinary sediment in renal transplantation.

The value of exfoliative urinary cytology for the diagnosis of different pathological conditions in renal transplantation is widely recognized. The method, however, has not yet gained full acceptance, mainly because identification of the different cells is not always possible by means of standard staining techniques. In view of its characteristics, flow cytometry (FC) seems to represent a consistently reliable, rapid and innovative approach for differentialing the various cells present in the urinary sediment and assessing their number. This study gives the examination result of 223 urinary specimens from 127 transplanted patients selected according to pathology. Sediment cells, collected from fresh urine samples, were washed, treated with a lysing solution, resuspended in saline solution and directly analysed in a FACSCAN cytometer. Morphological evaluation showed: a small number of cells in patients with stable renal function; a larger number of cells, with predominance of lymphocytes, during acute rejection episodes; an absolute predominance of neutrophils during bacterial infection; large-sized cellular debris in cases of post-transplant tubular necrosis; and small cell debris in cases of cyclosporine cytotoxicity. Lymphocyte surface-marker evaluation made it possible to differentiate lymphocyte populations observed during acute rejection episodes (cytotoxic T-cell, CD8 and HLA class II and NK cells) from those detected during bacterial infection (T-cell CD4 positive). These results suggest that urinary FC may be a reliable diagnostic tool in clinical renal transplantation.

Antigens, CD↗
PubMed1990

Hormonal changes in hemodialysis.

When chronic renal failure becomes advanced, the serum or tissue levels and/or the functions of most hormones are altered because of several interplaying mechanisms involving synthesis, transport, accumulation of inhibitors, abnormality of target organ responsiveness, and impaired renal clearance. As regular dialysis treatment is performed, most of these uremic hormone abnormalities are not reversed, and some of them may even get worse. The main endocrine derangements can be grouped as sexual hormone dysfunction, thyroid abnormalities, growth retardation, hormone-related disorders of metabolism, derangements of pressor substances, gastrointestinal peptide abnormalities, renal osteodystrophy, and anemia. The endocrine abnormalities play a major role as for the clinical and metabolic rehabilitation of dialysis patients.

Endocrine System Diseases↗
PubMed1985

[In-hospital and long-term prognosis in acute myocardial infarction. Comparative longitudinal study of 2 patient groups].

The in-hospital mortality, the causes of death, the actuarial survival curves were compared in two subsequent groups of patients admitted to our CCU for acute myocardial infarction: the first (group A) includes 791 pts, admitted from september '67 to december '72, the second (group B) includes 542 pts admitted from january '78 to june '80. The in-hospital mortality was significantly reduced in group B (A: 186/791, 23.5%; B: 72/542, 13,3%, p less than 0.01). This could be due to a reduction of the number of deaths for cardiogenic shock (A: 71/791, 9%; B: 30/542, 5.6%; p less than 0.01) and to reduction in the mortality rate for pulmonary oedema (from 6% to 1.5%, p less than 0.01), although the frequency of pulmonary oedema was the same during the two periods (A: 205 pts, 26%; B/156 pts 29%). We did not observe any significant difference in the long-term prognosis (54 months: A 79.3%, B 71.5%). The actuarial survival curves overlapped after the 1st semester after discharge. The most frequent cause of death during follow-up was a new myocardial infarction. None in the group A and only 3% in the group B were referred to the surgeon for coronary artery bypass grafting. We conclude that, in spite of a significant reduction of the in-hospital mortality, possibly related to the evolution in diagnosis and management of the disease, the long-term survival was not improved in a non-surgically treated population with myocardial infarction.

Adult↗
PubMed1981

Effect of nitroglycerin on ST potentials in the post-acute phase of myocardial infarction.

Thoracic electromaps were recorded before and after sublingual nitroglycerin (NG) in 26 subjects 15 and 30 days after acute myocardial infarction (MI), in order to evaluate the effect of the drug on injury potentials. Ten patients with documented left ventricular aneurysm were also studied 5 to 46 months after acute MI. Fifteen min after NG there was a significant decrease, compared with basal values, of ST segment elevations, blood pressure and rate-pressure product on both the 15th and 30th days. The degree of ST potentials reduction was not strictly related to the decrease of myocardial oxygen consumption, as indicated by the rate-pressure product. The response to NG on the 15th day did not predict accurately the evolution of injury potentials. In fact there was no significant correlation between percentages reduction of ST after NG on the 15th day and amplitudes of ST segment elevations present on the 30th day. In the patients with ventricular aneurysm, ST potential decrease and hemodynamic changes after NG were similar to those observed in the other groups studied. Our data suggest that it is not possible to differentiate between ST segment elevations associated with a dyssynergic area and those merely due to ischemic injury on the basis of NG sensitivity, and that ST segment elevations in the acute and subacute phase and long after MI have, at least in part, a similar electrophysiological significance.

Adult↗
PubMedDate not supplied

Predictive factors in chronic allograft nephropathy.

Chronic allograft nephropathy (CAN) is characterized by progressive renal dysfunction leading in many cases to graft loss. The pathogenesis of CAN involves both immune and nonimmune factors. Concerning immune factors, one of the most remarkable predictors of CAN is acute rejection, which is associated with a worse prognosis if there are multiple episodes or when late onset occurs. Delayed graft function is also a major risk factor for CAN because of a correlation between late restoration of renal function after transplantation and long-term decreased graft survival. High creatinine levels at 6 months and 1 year after transplantation, proteinuria, viral infections, and cardiovascular risk factors are additional significant parameters for the development of CAN. Recent findings suggest that a high renal segmental arterial resistance index measured by Doppler ultrasonography in intrarenal vessels is associated with poor allograft function. Moreover, the study of patient genetic profile represents a new approach to identify predictive factors for CAN.

Chronic Disease↗
PubMedDate not supplied

[Therapy strategies in the prevention of chronic allograft nephropathy].

Chronic allograft nephropathy (CAN) is an anatomical and clinical alteration, characterized by proteinuria, hypertension and a progressive decline in kidney function, which begins at variable times (months, years) and can lead to the loss of the transplanted organ. CAN pathogenesis, which remains to be fully clarified, involves both immunological (early acute rejection, hyperimmunization, HLA-mismatches between donor and recipient, suboptimal immunosuppression, etc) and non-immunological factors (ischemia/reperfusion injury, reduced nephron mass, age differences between donor and recipient, dialysis time, hypertension, dislipidemia, proteinuria, etc). The possible prevention strategies for CAN consist of procedures aimed at the reduction of some potential risk factors: optimization of the conditions for organ explantation, diminution of ischemia/reperfusion injury, aggressive pharmacological treatment of acute rejection episodes, routine utilization of anti-hypertensive and hypolipidemic agents, and appropriate and rational immunosuppressive regimen. Moreover, some categories of immunosuppressive drugs, such as calcineurin inhibitors, can have a nephrotoxic effect, often regardless of therapeutic dosage. The introduction in clinical practice of novel immunosuppressive drugs with no nephrotoxicity, like mycophenolate mofetil and rapamycin, makes therapeutical strategies able to reduce the incidence of CAN feasible.

Chronic Disease↗