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Francesco Locatelli

Publications and source records attributed to Francesco Locatelli.

At least 91 records · Page 5Linked to original sources
PubMed2002

The role of blood volume reduction in the genesis of intradialytic hypotension.

BACKGROUND: The aim of this multicenter prospective study was to investigate the role of relative blood volume (RBV) reduction on intradialytic hypotension. METHODS: One hundred twenty-three patients on chronic hemodialysis therapy were considered a priori normotensive (reference group A), intradialytic hypotension prone (group B), and hypertensive (group C). RBV was continuously monitored, and diastolic and systolic blood pressure (SBP) and heart rate (HR) were measured at 20-minute intervals during three dialysis sessions. RESULTS: Intradialytic RBV reduction was -13.8% +/- 7.0% and similar in the three groups (P = 0.841). SBP and RBV decreased during dialysis, with a sharp initial decrease (in the first 20 minutes for SBP and the first 40 minutes for RBV), followed by a slower decrease. The lying bradycardic response before dialysis was less in group B than group A (a decrease of 3 +/- 7 versus 9 +/- 9 beats/min; P < 0.001). When symptomatic hypotension occurred, RBV reduction was not significantly different from that recorded at the same time during hypotension-free sessions (-13.9% +/- 6.4% versus -12.7% +/- 5.2%; P = 0.149). Group, baseline plasma-dialysate sodium gradient, RBV line irregularity, and early RBV and HR reduction during dialysis influenced the relative risk for symptomatic hypotension with a sensitivity of 80% versus 30% for RBV alone. CONCLUSION: We found no difference in reduction in RBV in the three groups and no critical RBV level for the appearance of symptomatic hypotension. With variables easily available within 40 minutes of dialysis, RBV monitoring increases the prediction of symptomatic hypotension.

Aged↗
PubMed2002

The epidemiology of end-stage renal disease in Iran in an international perspective.

INTRODUCTION: The epidemiology of end-stage renal disease (ESRD) and renal replacement therapy (RRT) is under continuous evolution all over the world. We report here the epidemiological analysis of ESRD and RRT in Iran and discuss it against the background of the international situation. METHODS: This epidemiological report is based on data from centre questionnaires which were collected in Iran from 1997 onwards, with a response rate of 100%. RESULTS: The prevalence/incidence of RRT patients were 238/49.9 p.m.p. in the year 2000. Haemodialysis and kidney transplantation were the most common RRT modalities, accounting for 53.7% and 45.5% of prevalent RRT patients, respectively. The proportion treated by peritoneal dialysis was very low (<1%). Home haemodialysis was not performed. The majority of haemodialysis centres used synthetic membranes (70%) and 100% of the sessions were performed using acetate as a buffer; 42.5% of haemodialysis patients were treated with a twice-weekly regimen, whilst 49.6% were on the standard thrice-weekly regimen. The majority of RRT patients in Iran were young to middle aged. The great majority of renal allografts came from living donors (mainly unrelated to recipients). The main renal diseases leading to ESRD were diabetes and hypertension. The third most common category was "cause unknown". CONCLUSION: The epidemiology of RRT in Iran is characterized by: (i) young patient age (younger than the international average); (ii) high proportion of patients receiving renal allograft; (iii) use of living-unrelated donors as the major source of renal allografts.

Adolescent↗
PubMed2002

Nutritional status in dialysis patients: a European consensus.

BACKGROUND: Malnutrition is common in dialysis patients and closely related to morbidity and mortality. Therefore, assessment of nutritional status and nutritional management of dialysis patients play a central role in everyday nephrological practice. METHODS: Achieving a consensus on key points relating to pathogenesis, clinical assessment, and nutritional management of dialysis patients. RESULTS: The assessment of nutritional status should be based on clinical assessment and biochemical parameters, including history of weight loss, per cent standard weight, body mass index, muscle mass, subcutaneous fat mass, and plasma albumin, creatinine, bicarbonate and cholesterol. Co-morbid conditions should be assessed and C-reactive protein (CRP) measured--as a marker of inflammation--as there is a close relation between malnutrition, on one side, and co-morbid conditions and inflammation on the other. For a more detailed assessment, subjective global assessment of nutritional status is a well-validated tool, and dual-energy X-ray absorptiometry (DEXA) is a useful method for routine assessment of lean body mass. Anthropometric methods are also useful. They are cheap and easy to apply, although less precise than DEXA. The recommended daily protein intake is at least 1.2 g/kg standard body weight and the energy intake 35 kcal/kg standard body weight (BW), in patients <60 years, and 30 kcal/kg standard BW in patients >60 years. The standard bicarbonate level should be at least 22 mmol/l. If CRP is >10 mg/l, it is important to seek and treat the underlying cause. Adequate dialysis (for haemodialysis: Kt/V >1.2) should be ensured and, although no definite evidence of the importance of dialysis water quality is available, the opinion of the authors is that the water quality should be high. The role of the biocompatibility of the dialysis membrane is still not clear. The dietitian plays a pivotal role in the nutritional care of dialysis patients, and patients should be provided with dietary counselling from the start of substitutive treatment in order to meet the recommended nutritional intakes. Dietary counselling can also play an important role in an integrated treatment of hyperphosphataemia, although most patients will also need phosphate binders if they have an adequate protein intake. CONCLUSION: Malnutrition assessment and treatment is a great challenge for nephrological care. Achieving evidence-based consensus can help in implementing the progress of knowledge in clinical practice.

Body Mass Index↗
PubMed2002

Management of disturbances of calcium and phosphate metabolism in chronic renal insufficiency, with emphasis on the control of hyperphosphataemia.

BACKGROUND: Disturbances of calcium-phosphate (Ca-P) metabolism in chronic renal insufficiency (CRI) play an important role not only in bone disease (renal osteodystrophy) but also in soft tissue calcification, with an increased risk of vascular calcification, arterial stiffness, and worsening of atherosclerosis. METHODS: Discussion in order to achieve a consensus on key points relating to pathogenesis, clinical assessment, and management of renal osteodystrophy in dialysis patients. RESULTS: Secondary hyperparathyroidism develops primarily as a consequence of reduced active vitamin D production by the kidneys and phosphate retention, with the development of hyperphosphataemia, hypocalcaemia, and increased parathyroid hormone (PTH) levels. The same factors over the long term cause parathyroid gland hyperplasia and autonomous PTH production (tertiary hyperparathyroidism). As hyperphosphataemia and increased CaxP product have been associated with increased mortality in dialysis patients, hyperparathyroidism should be prevented and managed, starting in the pre-dialysis period, by calcium/vitamin D supplementation. Hyperphosphataemia is usually treated by means of intestinal phosphate binders, but different types of binders have been used. The traditional aluminium-based phosphate binders are certainly effective, but have the drawback of side effects due to aluminium absorption (osteomalacia, encephalopathy, microcytic anaemia). Calcium-containing phosphate binders (calcium carbonate or calcium acetate) have mainly been used for the last 10-15 years. However, they aggravate metastatic calcification, particularly if they are taken together with vitamin D analogues and a high calcium dialysate concentration. New calcium- and aluminium-free phosphate binders have recently been developed and may be useful, particularly in patients with metastatic calcification and/or hypercalcaemic episodes, in order to reduce the phosphate burden in the absence of an additional calcium load. New vitamin D analogues and calcimimetic drugs are also being developed for PTH suppression, with the goal to minimize or even entirely avoid hypercalcaemia and/or hyperphosphataemia. A suitable dialysate calcium concentration is important and must take into consideration the medical therapy and the calcium balance on an individual patient basis. Surgical parathyroidectomy is the ultimate means of treating hypercalcaemic hyperparathyroidism, when medical therapy has failed. CONCLUSION: Achieving an evidence-based consensus can give clinicians a useful tool for the treatment of disturbances of Ca-P metabolism in CRI: this has become an important objective in nephrological care, particularly as ageing and increased risk of atherosclerosis have become major issues in the dialysis population.

Bone Diseases↗
PubMed2002

The importance of early detection of chronic kidney disease.

Despite the absence of precise epidemiological data, we know there are a great many patients in the conservative phase of chronic kidney disease (CKD). The incidence and prevalence of renal replacement therapy (RRT) is increasing worldwide. As well as being a large and growing clinical problem, CKD is of an economic and organizational concern, since RRT consumes a considerable proportion of health care resources. In this context, any medical intervention that may prevent the progression of CKD towards end-stage renal disease (ESRD) is extremely important. Improving the patients' cardiovascular status is also a major objective in the management of this population, as cardiovascular disease (CVD) is the leading cause of morbidity and mortality for dialysis patients. Several interventions to delay the progressive loss of renal function and/or to prevent the development of CVD are now available. These include low-protein diets; correction of calcium-phosphate disorders and anaemia; blood pressure and proteinuria control; and smoking cessation. Other interventions, such as the administration of lipid-lowering agents, anti-inflammatory drugs, and anti-oxidant agents are emerging as particularly promising therapeutic approaches, although prospective, controlled, randomized clinical trials are needed to demonstrate their clinical usefulness. Intervention in the conservative phase of CKD is likely to be more effective if performed as early as possible in the course of the disease, since it has been widely demonstrated that early and regular nephrology specialist care is associated with decreased morbidity and mortality.

Anemia↗
PubMed2002

Optimizing dose and mode of renal replacement therapy in anaemia management.

Iron supplementation is probably the most important factor affecting response to treatment with recombinant human erythropoietin (rHuEPO) in patients with renal anaemia. However, the adequacy of dialysis is also significant. Many factors affect the process of dialysis and its effects. The purity of water used to make up the dialysate from concentrate is important. Inhibitors of erythropoiesis including ions and disinfectants may often be present in treated mains water. In addition, microbiological and pyrogenic contamination of the dialysate frequently occurs, sometimes leading to development or aggravation of anaemia in haemodialysis (HD) patients and also causing an immune response via cytokine activation. Inhibitors of erythropoiesis are also present in endogenous blood in patients with impaired renal function. Adequate dialysis is responsible for removing these mainly small, and possibly medium and large inhibitor molecules, thereby improving anaemia and enhancing response to rHuEPO. The biocompatibility and flux of the membrane used in HD may also have an effect. The removal of medium or large inhibitors of erythropoiesis is inefficient with cellulose membranes, but can potentially be achieved by using more permeable, high-flux membranes. However, in patients with adequate dialysis and sufficient iron and vitamin supplementation, the beneficial effects of a switch from standard cellulose to high-flux membranes have yet to be proven conclusively. Another area in which positive results on correction of anaemia have been seen in small studies is in the use of on-line haemodiafiltration, haemofiltration, or sterile dialysate. However, further large, controlled studies are needed to confirm these effects.

Anemia↗
PubMed2002

Is it the agent or the blood pressure level that matters for renal protection in chronic nephropathies?

Some antihypertensive agents may be capable of reducing chronic renal insufficiency (CRI) progression because they halt some of the pathogenic mechanisms involved in renal damage. Although this effect seems to be partially independent of BP reduction, it is still unclear whether these drugs are really superior to other antihypertensive agents when the BP values recommended by the present guidelines are actually achieved. This is particularly true when considering that, in published trials, target and achieved BP values were constantly higher than those nowadays recommended. Furthermore, in the majority of these studies, patients treated with ACE-inhibitors (ACE-I) or Angiotensin II receptor antagonists (ATIIRA) achieved lower BP values than those in control groups and BP values during 24 h were not recorded. Anyway, taking into account the role of baseline and follow-up BP values, the treatment effect remained significant in almost all of the multivariate models. These findings suggest that the renoprotective effect of these agents (ACE-I, ATIIRA) is partially independent of better BP control. However, caution should be paid in attributing true biologic renoprotective properties to drugs just on the basis of statistical adjustments of BP values, although robustly performed, without being aware of what those BP values actually reflect.

Angiotensin Receptor Antagonists↗
PubMed2002

Can immunosuppressive therapy be useful in IgA nephropathy when the 'Point of No Return' has already been exceeded?

Immunosuppressive treatment of IgA nephropathy (IgAN) has been a controversial issue since many years, mainly because of skepticism on awaited results and fear of possible side effects. Some authors proposed the existence of a 'point of no return', after which the worsening in renal function becomes inexorable and treatment ineffective. Indeed, the decision to treat these patients is easily followed by disappointment due to lack of favorable results. We report the case of a 24-year-old woman with a diagnosis of IgAN with advanced sclerosis and chronic renal failure. After treatment with a 6-month steroid course, she experienced a long-lasting stabilization of renal function (serum creatinine) and decrease in proteinuria (from 2.9 to 0.46 g/24 h) that still persisted at the end of follow-up (48 months). Analysis of this case and review of the literature suggest that immunosuppressive treatment could delay the beginning of renal replacement therapy in the advanced phase of IgAN. However, the results of long-term, randomized, controlled, adequately sized trials are awaited.

Adult↗
PubMed2002

Kidney and liver involvement in cryoglobulinemia.

Cryoglobulinemia is a pathological condition characterized by the presence in the blood of a group of proteins (cryoglobulins) showing the common property of precipitating from cooled serum. Mixed cryoglobulins (MCs) are composed of a polyclonal immunoglobulin G (IgG) bound to another immunoglobulin that acts as an anti-IgG rheumatoid factor; 2 types of MCs can be identified. The origin is not clear in 30% of all MCs, and this subset of cryoglobulinemias is called "essential." The great majority (up to 90%) of patients with essential MC (EMC) of both types has been related to HCV infection. The renal involvement in essential MC has been observed in 2% to 50% of patients in reported series. A well-characterized pattern of glomerular disease termed "cryoglobulinemic glomerulonephritis" is present in individuals with type-II EMCs in serum and IgMk RF being the most frequent monoclonal component. Aspecific and infrequent glomerular lesions occur in EMC patients with type III cryoglobulins. The most frequent histologic picture of cryoglobulinemic GN is that of membranoproliferative GN (MPGN) with subendothelial deposits. However, cryoglobulinemic GN may have some distinctive features that differentiate it from idiopathic type-I MPGN. Evidence of liver involvement has been found in 60% to 80% of EMC patients. Recent data support the notion that the stage of liver disease in patients with type II or III MC has association with the prevalence of cryoglobulinemia. Few controlled trials have been published on the treatment of HCV-related MC; in addition, the majority of the patients enrolled in these trials had an unclear renal involvement. Interferon (IFN) is an effective drug for the treatment of patients with HCV-associated MC and cryoglobulinemic GN. In the presence of acute cryoglobulinemic GN, IFN does not prevent progression of renal damage; combination therapy with cytotoxic ad anti-inflammatory drugs, and sometimes plasma exchange, is recommended. Prospective controlled trials are underway on this purpose.

Antiviral Agents↗
PubMed2002

Kidney and liver involvement in monoclonal light chain disorders.

Monoclonal light chains (LCs) are responsible for a wide spectrum of renal and hepatic diseases, that above all include amyloid light-chain (AL) amyloidosis and light chain deposition disease (LCDD). Amyloid deposits stain for Congo red on light microscopy and have fibrillar aspect on electron microscopy, whereas deposits in LCDD are positive using monotypic LCs on immunofluorescence and have a granular aspect on electron microscopy. Sometimes fibrillar and granular deposits are observed in the same organ or in different organs of the same patient. Kidney and liver involvement is a frequent finding, both in primary amyloidosis (AL amyloidosis) or in LCDD. Renal manifestations include proteinuria, nephrotic syndrome, and progressive renal failure. End-stage renal disease requiring dialysis is observed in about 20% of patients with AL amyloidosis and in 70% of patients with LCDD. The mean survival time is about 12 to 18 months in AL amyloidosis and 34 months in LCDD. The most important prognostic factor is severe cardiac involvement, which reduces the mean survival to only 6 months. Hepatic manifestations include hepatomegaly, portal hypertension, ascites, intrahepatic cholostatic jaundice, and hepatic insufficiency. The mean survival of patients with liver damage is 14 months, but it is reduced to 5 months in patients with cholostatic jaundice. Contemporary kidney and liver involvement is usually observed on histologic examination, less frequently as clinical manifestation. No specific treatment exists for AL amyloidosis and LCDD, and the prognosis remains severe. The aim of treatment is to suppress proliferation of the abnormal clone of plasma cells and remove tissue deposits. The regimens, including melphalan-prednisone (MP) or vincristine-doxorubicin-dexamethasone (VAD), are used both in AL amyloidosis or in LCDD with some effectiveness. New approaches, especially the use of 4'-iodo-4'deoxydoxorubicin, could achieve better results. Dialysis seems to not worsen the outcome in both diseases because survival of patients on dialysis is not different from that of patients not reaching uremia. Also, kidney and liver transplantation is effective, though amyloidosis or LCDD may occur in transplanted organs. The most interesting therapeutic approach is autologous-blood stem-cell transplantation, which may produce a complete remission of the plasma-cell dyscrasia and a substantial improvement of clinical manifestations related to LC deposits.

Amyloidosis↗
PubMed2001

Survival and development of cardiovascular disease by modality of treatment in patients with end-stage renal disease.

Patients undergoing dialysis are at high risk for cardiovascular disease (CVD). The aim of this study was to evaluate the influence of hemodialysis (HD) versus peritoneal dialysis (PD) on survival and the risk of developing de novo CVD. Of the 4191 patients with end-stage renal disease (ESRD) who started renal replacement treatment (RRT) in Lombardy between 1994 and 1997, 4064 (who were on dialysis 30 d after the start of RRT) were considered for survival analysis: 2772 were on HD (mean age 60.9 yr; 21.2% diabetic) and 1292 on PD (mean age 63.6 yr; 16% diabetic). The 3120 patients who were free of CVD at the start of RRT were included in the analysis of the risk of developing de novo CVD. HD and PD were compared by use of a Cox-regression proportional hazard model, stratified by diabetic status; the explanatory covariates were age and gender. The death rate was 13.3 per 100 patient-years (13.0 on HD and 13.9 on PD); 197 (6.3%) of the 3120 patients included in the CVD analysis developed de novo CVD (128 on HD and 69 on PD). After adjustment for age, gender, and established CVD and stratification by diabetic status, there was no significant between-treatment difference in 4-yr survival (relative risk [RR], 0.91; 95% confidence interval [CI], 0.79 to 1.06). The risk of de novo CVD did not differ significantly by treatment modality (RR, 1.06; 95% CI, 0.79 to 1.43). The risk of mortality and de novo CVD for new patients with ESRD assigned to HD or PD was similar in Lombardy in the period 1994 through 1997.

Aged↗
PubMed2001

Parathyroidectomy in patients on renal replacement therapy: an epidemiologic study.

Secondary hyperparathyroidism is a frequent complication of long-term dialysis treatment, and despite recent advances in medical therapy, surgical parathyroidectomy (PTx) is necessary in a considerable number of uremic patients. A prevalence of PTx of 22% was reported in Europe in 1988 in patients on dialysis from 10 to 15 yr, but no large-scale epidemiologic study has been published since then. The aim of the study was to evaluate the prevalence, incidence, and risk factors for PTx in patients on renal replacement therapy (RRT) in Lombardy and to determine whether the incidence has changed over time. The study involved 14,180 patients included in the Lombardy Registry of Dialysis and Transplantation who received RRT for end-stage renal disease (ESRD) between 1983 and 1996. Cox-proportional hazards regression models were used to evaluate the risk factors of PTx, the explanatory covariates being age on admission to RRT, gender, underlying renal disease (nondiabetic or diabetic nephropathy), and dialysis modality (peritoneal dialysis or hemodialysis). The prevalence of PTx in the 7371 ERSD patients who were alive on December 31, 1996, was 5.5% and increased with the duration of RRT (9.2% after 10 to 15 yr, 20.8% after 16 to 20 yr). Similarly, the incidence of PTx increased from 3.3 per 1000 patient-years in patients who had been on RRT for <5 yr to 30 per 1000 patient-years in those receiving RRT for >10 yr. The Cox regression models showed that the relative risk for PTx was significantly higher in women and lower in elderly and diabetic patients. The relative risk for PTx (adjusted for gender, age, and nephropathy) was higher in the patients on peritoneal dialysis than in those on hemodialysis and decreased after transplantation. During the course of a follow-up of 7 yr, the incidence of PTx in patients who started RRT between 1990 and 1992 was no different from that observed in patients who started RRT between 1983 and 1985. In conclusion, the prevalence and incidence of PTx in patients receiving RRT in Lombardy is lower than that in Europe and Italy as a whole, as reported by the 1988 European Dialysis and Transplantation Association Registry; its frequency has not changed significantly during the past few years. The need for PTx decreases markedly after successful transplantation. The epidemiologic finding that the rate of PTx is greater in women, young patients, and individuals who do not have diabetes suggests the need for a more aggressive medical treatment of secondary hyperparathyroidism particularly in such patients.

Adult↗
PubMedDate not supplied

Sodium balance in hemodialysis therapy.

Water and sodium overload is the predominant factor in the pathogenesis of hypertension in dialysis patients. In many dialysis patients, dry weight is not reached because of an imbalance between the interdialytic accumulation of water and sodium and the brief and discontinuous nature of routine dialysis therapy. During dialysis, sodium is removed by convection and to a lesser degree by diffusion. However, with supraphysiologic dialysate sodium concentrations, diffusive influx from dialysate may occur, especially in patients with low predialytic plasma sodium concentrations. Measuring sodium removal during dialysis is difficult and hampered by the variability in conventional sodium measurements. Ionic mass removal by continuous measurement of conductivity in the dialysate ports appears to be a promising tool for the approximation of sodium removal during dialysis. While the beneficial effects of concomitant water and sodium removal on blood pressure control in dialysis patients are undisputed, it is less well known whether a change in hydrosodium balance solely by reducing dialysate sodium is beneficial. Considering the inherent dangers of such an approach (intradialytic hemodynamic instability), the beneficial effects of strict dietary sodium restriction appear to be of much larger clinical benefit. It has become possible to individualize dialysate sodium concentration by means of online measurements of plasma conductivity and adjustment of dialysate conductivity by feedback technologies. The clinical benefits of this approach deserve further study. Still, reducing dietary sodium intake remains the most important tool in improving blood control in dialysis patients.

Blood Pressure↗
PubMedDate not supplied

Hypertension in dialysis: pathophysiology and treatment.

Hypertension is a major modifiable risk factor for cardiovascular disease, which is the main cause of morbidity and mortality in the dialysis population; therefore, blood pressure (BP) values of <140/90 mmHg (or <160/90 mmHg in the elderly) are recommended. As extra-cellular volume (ECV) expansion is the main pathophysiological determinant of hypertension in dialysis patients, efforts should be made to correctly estimate and achieve the patient's dry body weight. Adequate dialysis treatment time, avoiding the high ultrafiltration rates associated with short treatment times, can greatly help in controlling BP values, at least in part by improving cardiovascular stability. The most promising tool in reducing cardiovascular instability is the use of the conductivity kinetic model, which is easy to apply at each dialysis session without any extra-cost and can also provide information on dialysis dose and vascular access function. On-line monitoring of blood volume (BV) changes has also been used. Convective techniques have long been claimed as providing better cardiovascular stability, compared to diffusive techniques, but solid evidence is still lacking. Anti-hypertensive drugs should be used only when, despite the patient being at his dry body weight, BP values are not adequately controlled. There are no studies specifically addressing which classes of anti-hypertensive drugs provide better organ-protection in dialysis patients. However, the current opinion is that adequate BP control should be guaranteed, irrespective of which classes of drugs are used. Then, ACE inhibitors, angiotensin II receptor antagonists and beta-blockers may be recommended as first choice drugs, given their protective effects in patients at high risk for, or affected by, cardiovascular disease.

Age Distribution↗