[Antiviral prophylaxis and pre-emptive therapy for the prevention of Cytomegalovirus infection in renal transplant recipients: guideline from the Italian Society of Nephrology]. / Profilassi con farmaci antivirali e pre-emptive therapy per la prevenzione dell'infezione da Citomegalovirus nel trapianto di rene: Linea Guida.

BACKGROUND: The current 3rd edition of the Italian Society of Nephrology guidelines has been drawn up to summarize evidence of key intervention issues on the basis of systematic reviews (SR) of randomized trials (RCT) or RCT data only. In the present guideline, evidence of antiviral prophylaxis and pre-emptive treatment for preventing cytomegalovirus (CMV) infection in kidney transplant recipients is presented. METHODS: SR of RCT and RCT on antiviral prophylaxis and pre-emptive treatment for CMV infection in kidney transplant recipients were identified referring to a Cochrane Library and Renal Health Library search (2005 update). RESULTS: Evidence from 4 SR of RCT was gathered to address this issue. Methodological quality of available RCT included in these SR was suboptimal. Antiviral prophylaxis is associated with a significant reduction in the risk of CMV infection and all-cause mortality in CMV-negative and CMV-positive renal transplant recipients from CMV-positive donors, regard-less of the immunosuppressive treatments used (evidence from SR). Pre-emptive therapy has been found to be effective in preventing CMV disease but not all-cause mortality in these patients, even if evidence is less satisfactory compared to data on antiviral prophylaxis (evidence from SR). There is insufficient evidence of conclusive recommendations on treatment of CMV-negative recipients of renal transplants from CMV-negative donors. CONCLUSION: In kidney transplant patients current available evidence supports the hypothesis that antiviral prophylaxis and pre-emptive therapy are effective in preventing CMV disease; but antiviral should be the treatment of choice. Further studies are necessary on the treatment of CMV-negative recipients from CMV-negative donors.

[Substitutive therapies in sepsis and acute renale failure]. / Trattamenti emergenti e/o alternativi nell'nsufficienza renale acuta associata a sepsi.

Substitutive treatment of sepsis associated acute renal failure is an emergent challenge in the intensive care unit due to the number of cases and to the high mortality rate. Standard hemofiltration is unable to improve survival, since a high mortality rate is sustained by the septic process. New therapeutic approaches currently available are based on the increased clearance of molecules ranging 10-30 kDa considered important in the physiopathology of sepsis and multiorgan failure. Clinical experiences in progress are: (1) adsorption resins able to bind bacterial products, cytokines, anaphylotoxins and several inflammation mediators; (2) the bioartificial kidney, that is the addition to hemofilter of human tubular cell culture grown in devices in order to mimic metabolic tubular function to a traditional hemofilter; (3) increased exchange volumes (high volume hemofiltration), up to 0-100 L/24 hr and; (4) increased membrane permeability associated with either discarded ultrafiltrate (high cut-off membranes) or plasma substitution plasmapheresis with regeneration by sorbents technology (C FA). Generally, by applying these new technologies to septic shock patients, the observed survival was higher than that predicted by the gravity score. While these results are encouraging, they are not conclusive and need further study.

[Cachexia during dialysis]. / Cachessia in corso di dialisi.

In the Italian language, the term cachexia is a rather picturesque synonym of "marasma senile", "senile marasmus", an old definition involving not only old-age, but specifically senility, the end of the ageing process and marasmus, a stagnant and hopeless situation in which all superior organised functions have disappeared. The problem of cachexia during dialysis is complex and several discordant opinions exist at this regard, partly accounted by different definitions of this sluggish entity (or non entity). Actually, the basic question is very simple: is cachexia the cause or the effect of failure of dialysis treatment? The aim of this study was an evaluation of epidemiological data from the Dialysis and Transplantation Registry of Piedmont, a northern Italian Region with about 4,350,000 inhabitants, 22 public dialysis Centers, open acceptance to dialysis since the mid seventies, a multiple choice dialysis system developed in the eighties. In the period 1981-1995, 764 patients died in conditions of cachexia. This figure is 20.9% of all deaths recorded, 27.4% over age 65 and 34.7% over age 75. Despite a likewise significant increase in age and presence of comorbid factors, an improvement of patients survival, that reach statistical significance in the old age group (> or = 65 yrs), was observed.

[Uremic pruritus]. / Il prurito uremico.

Among the various dermatologic abnormalities that can be associated with advanced chronic renal failure and dialysis therapy, pruritus is certainly the most disturbing disorder. Pruritus is an unpleasant, vexing sensation that provokes an intense desire to scratch. In the past the pruritus was considered from the neurophysiologic point of view as a submodality of pain, but more recent research showed that pain and pruritus are sensations which are carried through different populations of primary sensory neurons. The causes of pruritus in uremic patients are still unknown: xerosis, intradermic microprecipitation of divalent ions, hyperparathyroidism, peripheral neuropathy, allergic reactions and hypersensitivity, histamine and others have been considered as pathogenetic factors. The uncertainty on the causes is in part responsible for the different approach and results, unsatisfactory in many cases. In this paper we will review the neurophysiology, the pathogenesis and the possible therapeutic approaches to uremic pruritus.

[Diabetes mellitus is currently one of the most frequent causes or associated causes of uremia. Data from the Piedmont registry of dialysis and transplantation (update, December 1993)]. / Il diabete mellito rappresenta attualmente una delle cause-concause più frequenti di uremia. Dati del registro piemontese di dialisi e trapianto (aggiornamento al dicembre 1993).

A regular dialytic treatment of diabetic patients is until accepted from about twenty years in many areas. Aim of this work was a retrospective analysis of main clinical and survival data of diabetic patients (diabetic nephropathy or diabetes as comorbidous factor = 659 cases) admitted for dialysis in Piedmont (Northern Italy Region about 4,400,000 inhabitants) in the period 1981-1993 (functional recovery and follow-up < 1 month excluded). A progressive increment in incidence of diabetic patients was seen mostly in the aged. At 12/31/1993, 263 of 2404 patients admitted for dialysis were diabetics (10.9%); the majority of them was treated in Hospital Centers with bicarbonate haemodialysis (54.4%), while a small group was treated with CAPD (12.9%). During the years ¿80 was seen a progressive leaving of CAPD as first choice method in this population and in the last period the orienteering is the utilization of mixed methods (diffusive-convective as first choice). As regards the survival are not prominent significant differences between this cohort and the cohort affected by vasculopathy as comorbidous factor (86.2 and 54.2% in diabetics vs 78.6 and 55.2% in patients affected by vasculopathy at 1 and 3 years--p = 0.3481; patients aged 45-64 years). In conclusion the cohort of diabetic patients represent a good marker of the clinical problems of the elder population with high clinic risk, in progressive increasing in our Region.

Dialysis in the elderly: improvement of survival results in the eighties.

Analysis of long-term dialysis results is the cornerstone of renal replacement therapy evaluation. Elderly patients may be considered a crucial cohort, since subtle differences may be enhanced in a population of lower life expectancy. The aim of the study was an analysis, from the Piedmont Registry of Dialysis and Transplantation, of the results obtained in 1981-1992 (northern Italy, about 4,400,000 inhabitants, 21 dialysis centres, open acceptance since mid-1970s) in patients aged > or = 65 years (475 patients started treatment in 1981-1985, 1026 in 1986-1992). As a first treatment, during the 12 years considered acetate haemodialysis decreased sharply; bicarbonate haemodialysis is currently the standard treatment (68%). Peritoneal dialysis is stable (21%), and haemodiafiltration is increasing (8%). Shifts between treatments are frequent: 15% of elderly patients changed treatment at least once in 1991-1992. Nephroangiosclerosis/ischaemic renal disease, undefined causes and diabetes mellitus are the major causes of end-stage renal disease; 57.3% of patients have high risk conditions in addition to age. In this cohort of patients, mean age of new cases starting dialysis significantly increased in 1986-1992 (72.7 +/- 5.4 years) versus 1981-1985 (71.3 +/- 4.5; P < 0.001). Despite this, survival at 2 years increased significantly from 54.6% in the period 1981-1985 to 59% in the period 1986-1992 (P < 0.05). Even in an ageing dialysis population, therefore, choice of an open dialysis system with easy changes among treatments allowed improvement of survival results; further technical advances may help in maintaining present trends.

[The value of albumin and cholesterol blood levels as indicators of the risk of death in dialysis. Working Group of the Piedmont Registry of Dialysis and Transplantation]. / Il valore dei livelli di albuminemia e colesterolemia come indicatori del rischio di morte in dialisi. Gruppo di lavoro dell'RPDT.

In recent years, the availability of large epidemiological series allowed identification of biochemical outcome markers in the dialysis population. Interest towards albumin and cholesterol levels is motivated by their easy availability and by the presence of a strong short-term effect on mortality and morbidity. The aim of the study was an analysis of the relationship between albumin and cholesterol levels at start of dialysis and mortality (gross mortality and Kaplan Meier survival curves). Data were obtained from the Piedmont Regional Registry of Dialysis and Transplantation (Northern Italy Region, about 4,400,000 inhab, 20 Dialysis Centers, open acceptance since mid '70, yearly information on 100% of patients) in the period 1981-1990 (4734 patients on file). Only non diabetic patients with follow-up > = 1 month, who started treatment in the Region, were selected. Patients with renal function recovery were excluded. Albumin levels were dichotomized at 3.5 g/dl. Cholesterol was stratified into 3 levels (< 150, 150-250, > or = 300 mg/dl). The choice of dividing the study into 2 periods (1980-1985 vs 1986-1990) is due to the fact that 1984 has been the year of switch from acetate to bicarbonate dialysis. Prevalence of albumin and cholesterol under the normal range (22% and 15%) is low and rises with age and presence of high risk conditions. A a good correlation with the risk of death of these biochemical markers (stronger for albumin at least in the short term) was observed. No correlations are found with risk of death and elevated cholesterol levels (low number of cases).(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies to hepatitis C virus in kidney transplantation.

Ninety patients on dialysis, 241 cadaveric kidney donors and 27 cadaveric kidney recipients with a follow-up of 2 years, have been investigated as for anti-HCV positivity by means of 3 tests. As for patients on dialysis and cadaveric donors, the prevalence was 32 and 4%, respectively. As for transplanted patients, it must be noted that 4 negative recipients from positive donors seroconverted, but without any change in hepatic enzymes, while in 2 or 9 anti-HCV-positive recipients, hepatic enzymes increased after transplantation. Seroconversion in patients transplanted from a negative donor was not significantly different. We conclude that, according to their experience, anti-HCV positivity in the donors is not associated with a significant risk of infection in recipients of cadaveric grafts.

[High-efficiency hemodialysis. Review of the literature and initial clinical experience]. / L'emodialisi ad alta efficienza. Revisione della letteratura e prime esperienze cliniche.

A literature review allows us to distinguish two types of high efficiency therapy: HED (high efficiency dialysis), with low ultrafiltration coefficient membranes, and HFD (high flux dialysis), with high ultrafiltration coefficient membranes. Data reported show an unchanged hematochemical with the same, or better, treatment tolerance, but there are few data on hydrosaline balance (and correlate hypertension) and middle moleculas removal. Finally we report the experience of our centre in 59 months of treatment in four patients.

Scant reliability of Co/Ct ratio in urea kinetic formulas.

The ratio initial/final urea value is used in urea kinetic formulas. To assess its reliability we employed mass balances and urea clearances to study 15 hemodialysis treatments divided in several parts. The mass balances clearly indicated urea disequilibrium. In the first phases of dialysis, urea extraction, measured by dialysate collection, was lower than the corresponding change in urea pool, whereas in the later phases the opposite occurred. On account of this lack of equilibrium, clearances bases on the Co/Ct ratio (K2) are less reliable than standard clearances derived from total dialysate collection (K1): in the first quarter of dialysis, K2 is greater than K1 (p less than 0.01), while in the 3rd and 4th quarters it is lower. The comparison of clearances in a cumulative way showed a significant fall in K2 (p less than 0.01) while K1 remained stable. From a practical point of view, aberrations induced by non monocompartmental urea behaviour are negligible, and do not invalidate the usefulness of the single-pool Gotch model in clinical practice. However, at least in experimental work, the limits of urea kinetic formulas must be taken into account.

Transcellular disequilibrium and intradialytic catabolism reduce the reliability of urea kinetic formulas.

To elucidate the limits of single-pool models as regard aberrations induced by urea transcompartmental disequilibrium during urea kinetics, mass balances and fractional clearances were studied, and original formulas developed to calculate urea clearance and distribution volume. In the early dialytic phases, aberrations were more evident, with low kinetic volume (VK) values and kinetic clearance (KK) values double those obtained by dialysate collection (KDC). Over the whole session, both VDC and VK were underestimated (9.9 and 8.2%), compared with anthropometric data (VA). In 3 patients, the comparison of VA and VDC, and the behavior of effective body water clearance (KE), agreed with the hypothesis of dialysis-induced catabolism. Both disequilibrium and hypercatabolism can affect the reliability of the single-pool urea kinetic model; because of overlap, their effects are difficult to separate, and became particularly important in high-efficiency dialysis. A modified model, using V and CtET as input is suggested in order to establish the most appropriate dialysis prescription for uremia therapy.