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D Marcelli

Publications and source records attributed to D Marcelli.

At least 37 records · Page 2Linked to original sources
PubMed1996

Long-term effects of intravenous calcitriol therapy on the control of secondary hyperparathyroidism.

Although high-dose intravenous calcitriol has been shown to be effective in suppressing parathyroid hormone (PTH) secretion in dialysis patients with secondary hyperparathyroidism, an increasing number of patients is refractory to treatment. Only a few studies have evaluated the factors that can predict a favorable response to calcitriol, but contrasting results have been reported. This study was performed to evaluate the effect of high-dose intravenous calcitriol on parathyroid function and to investigate the factors that can predict a favorable response to treatment. Thirty-five dialysis patients were selected for intravenous calcitriol treatment (2 microg after dialysis for 12 months) because of increased PTH levels (>325 pg/mL). Before starting the treatment, the set point of calcium and the PTH-ionized calcium (ICa) curve was evaluated in each patient by inducing hypocalcemia and, 1 week later, hypercalcemia to maximally stimulate or inhibit PTH secretion. Parathyroid glands were assessed by high-resolution color Doppler ultrasonography. Throughout the study, calcium carbonate or acetate dosage was modified to maintain serum phosphate less than 5.5 mg/dL. Hypercalcemia was managed by reducing dialysate calcium to 5 mg/dL and, if necessary, calcitriol dose. The therapeutic goal was to reduce PTH levels below 260 pg/mL while maintaining normocalcemia. The patients who achieved the therapeutic goal were considered responders. Taking the data from the 35 patients together, we observed a significant decrease (P < 0.01) in alkaline phosphatase (from 252 +/- 106 IU/L to 194 +/- 81 IU/L) and PTH (from 578 +/- 231 pg/mL to 408 +/- 291 pg/mL), and a significant increase in serum ICa (from 5.1 +/- 0.2 mg/dL to 5.3 +/- 0.2 mg/dL; P < 0.001) after calcitriol therapy. PTH changes after therapy were not correlated to serum ICa changes, serum phosphate levels during treatment, and calcitriol dose. The response to therapy was heterogeneous because PTH levels markedly decreased over the treatment period in 18 responsive patients, whereas they increased or remained unchanged in 14 of 17 nonresponders. In three additional refractory patients, there was a decline in PTH of 20% to 35%, but this decline was associated with hypercalcemia. Pretreatment parathyroid gland size, serum ICa, PTH, maximal PTH induced by hypocalcemia, minimal PTH induced by hypercalcemia, the set point of ICa, and the ICa levels at which maximal PTH secretion and inhibition occurred were higher in the 17 refractory patients than in the 18 responsive patients. However, logistic regression analysis showed that among these parathyroid function parameters, the only significant predictors of a favorable response to calcitriol therapy were the parathyroid gland size and the set point of ICa. Throughout the study, serum phosphate and calcitriol dose were comparable in the two groups. In conclusion, the response to intravenous calcitriol therapy in dialysis patients with secondary hyperparathyroidism is heterogeneous, consisting of patients who are either responsive or refractory to treatment; refractoriness can be predicted by parathyroid volume and calcium set point.

Calcitriol↗
PubMed1996

ESRD patient mortality with adjustment for comorbid conditions in Lombardy (Italy) versus the United States.

The present study evaluated end-stage renal disease (ESRD) patient survival in Lombardy, Italy, and the United States (U.S.) using data from two registries, the Lombardy Dialysis and Transplant Registry (RLDT) and the U.S. Renal Data System (USRDS), respectively. For this purpose, 4,196 white patients (2,900 from the USRDS Case Mix Severity Study and all 1296 from RLDT) who started renal replacement therapy in 1986 and 1987 were studied. Compared to Lombardy patients, those in the USA were significantly older (mean age 59.9 +/- 16.4 vs. 55.9 +/- 14.7 years), had a lower proportion of males (53.7 vs. 62.1%), a greater proportion with diabetic nephropathy (29.9 vs. 9.7%) and a significantly greater proportion of patients with the recorded comorbid conditions (heart disease, peripheral vascular disease, cirrhosis, cachexia, malignancy). U.S. patients were less frequently treated with peritoneal dialysis (PD) by day 30 of ESRD (21.2 vs. 30.7). Survival was compared in the Cox proportional hazard regression model, using age, sex, comorbid conditions and early modality of treatment as explanatory covariates. Overall, 48% of the 4196 patients died during the 48 to 72 months follow-up to 12/31/91. Per 100 patient-years the gross death rate for USRDS patients was 28.7 compared to 13.0 of RLDT patients. The unadjusted death relative risk for RLDT was 0.439, that is, 56% lower death rate compared to USRDS patients. Age, sex, diabetic status, each of the recorded comorbid conditions and treatment modality were significantly related to survival and included in the model. The Cox cumulative survival adjusted for all these explanatory covariates survival was for U.S. patients 84.4% at one year, 67.0% at two years and 33.4% at five years, and for RLDT patients 88.3% at one year, 75.9% at two years and 45.9% at five years. The relative mortality risk (RR) for the patients treated in Lombardy adjusted for all the reported covariates was 29% lower than for US patients (RR = 0.71; P < 0.0001). This comparative risk varied significantly by age (P < 0.0001) and was 65 percent lower for Lombardy compared to U.S. patients in the age range 25 to 44 years (RR = 0.35) and about 20% lower for patients over age 65 years (RR = 0.80). This relative risk was mainly related to hemodialysis and was not statistically significant for PD patients. The observed lower mortality risk in Lombardy was less pronounced when adjusted for demographic and comorbid covariates, but was still large and therefore suggests the need for further studies regarding treatment related factors and unmeasured patient factors, particularly in hemodialysis patients.

Adult↗
PubMed1996

Effects of different membranes and dialysis technologies on patient treatment tolerance and nutritional parameters. The Italian Cooperative Dialysis Study Group.

There is increasing evidence that the biochemical and cellular phenomena induced by blood/ membrane/dialysate interactions contribute to dialysis-related intradialytic and long-term complications. However, there is a lack of large, prospective, randomized trials comparing biocompatible and bioincompatible membranes, and convective and diffusive treatment modalities. The primary aim of this prospective, randomized trial was to evaluate whether the use of polysulfone membrane with bicarbonate dialysate offers any advantage (in terms of treatment tolerance, nutritional parameters and pre-treatment beta-microglobulin levels) over a traditional membrane (Cuprophan). A secondary aim was to assess whether the use of more sophisticated methods consisting of a biocompatible synthetic membrane with different hydraulic permeability at different ultrafiltration rate (high-flux hemodialysis and hemodiafiltration) offers any further advantages. Seventy-one Centers were involved and stratified according to the availability of only the first two or all four of the following techniques: Cuprophan hemodialysis (Cu-HD), low-flux polysulfone hemodialysis (LfPS-HD), high-flux polysulfone high-flux hemodialysis (HfPS-HD), and high-flux polysulfone hemodiafiltration (HfPS-HDF). The 380 eligible patients were randomized to one of the two or four treatments (132 to Cu-HD, 147 to LfPS-HD, 51 to HfPS-HD and 50 to HfPS-HDF). The follow-up was 24 months. No statistical difference was observed in the algebraic sum of the end points between bicarbonate dialysis with Cuprophan or with low-flux polysulfone, or among the four dialysis methods under evaluation. There was a significant decrease in pre-dialysis plasma beta 2-microglobulin levels in high-flux dialysis of 9.04 +/- 10.46 mg/liter (23%) and in hemodiafiltration of 6.35 +/- 12.28 mg/liter (16%), both using high-flux polysulfone membrane in comparison with Cuprophan and low-flux polysulfone membranes (P = 0.032). The significant decrease in pre-dialysis plasma beta 2-microglobulin levels could have a clinical impact when one considers that beta 2-microglobulin accumulation and amyloidosis are important long-term dialysis-related complications.

Adolescent↗
PubMed1996

Proteinuria and blood pressure as causal components of progression to end-stage renal failure. Northern Italian Cooperative Study Group.

AIMS: To identify the prognostic factors possibly related to end-stage renal failure development. SUBJECTS AND METHODS: The prognostic factors affecting chronic renal failure progression were analysed in 456 patients who had participated in a formal, multicentre, prospective randomized trial aimed at verifying the role of protein restriction in slowing down or halting the progression of chronic renal failure. The 24-month follow-up foreseen by the protocol was completed by 311 patients and 69 reached an end-point. An inductive analysis on patient survival was made by using the Cox proportional hazard regression model, using a stepwise procedure in order to select only those factors which are significantly associated with survival. For each individual risk factor, a univariate descriptive analysis of survival was performed using the Kaplan-Meier technique. RESULTS: Underlying nephropathy, baseline plasma creatinine, proteinuria, and plasma calcium were all shown to be related to end-stage renal failure onset. Hypertensive patients (mean blood pressure > 107 mmHg) had a worst cumulative renal survival but the degree of proteinuria was even more important as a prognostic factor of renal death than hypertension. The cumulative renal survival of patients whose proteinuria decreased during the trial follow-up was better than those of patients without changes. However, the interaction between baseline lying mean blood pressure and proteinuria was not significant. CONCLUSIONS: Only primary renal disease and proteinuria were related to renal survival, being baseline plasma creatinine confounding factor. By blocking the possible causal role of proteinuria and hypertension, end-stage renal failure could be prevented in a significant percentage of patients.

Adolescent↗
PubMed1996

Recombinant hepatitis B vaccine use in chronic hemodialysis patients. Long-term evaluation and cost-effectiveness analysis.

The prevalence of hepatitis B virus (HBV) infection in our unit was 45% (86/190); there were 77 (40.5%) and 9 (4.7%) patients with previous and persistent HBV infection, respectively. Recombinant hepatitis B vaccine was given to 118 chronic HD patients with a regimen of 3 double doses administered intramuscularly at 0, 1 and 2 months, obtaining a seroprotection rate of 67% (79/118), 57% (45/79) being high responders. At month 24, 78% (40/51) maintained protective levels of anti-HBs, 45% (18/40) of them being high responders. There was a statistically significant difference between responder and non-responder patients with regard to nutritional parameters such as serum total proteins and mean levels of transferrinemia. The number of diabetic patients was significantly increased in the nonresponder group. Patients with persistent antibodies ('persistent responders') were younger and had a shorter duration of HD treatment compared to those responders who rapidly lost anti-HBs ('transient responders'). Serological positivity for antibodies against hepatitis B core antigen significantly facilitates the decrease of anti-HBs antibodies over time. We detected seven episodes of HBV infection among HD patients at our unit before the beginning of the vaccination program. On the contrary, there were no episodes of HBV infection among responder vaccinees during the 24-month follow-up period. After the initial cost of vaccination, a savings of US$ 3,272 per year was realized by the elimination of frequent serologic screening of vaccine responders.

Adolescent↗
PubMed1996

Virological and histological features of hepatitis C virus (HCV) infection in kidney transplant recipients.

BACKGROUND: Although there are some reports regarding prevalence of anti-HCV antibodies in kidney transplant patients, there are scarce data about viraemia, genotyping and liver histology of HCV infection in kidney transplant recipients. METHODS: We studied the prevalence of anti-HCV antibodies by second-generation screening and confirmatory assays in a cohort of 73 renal allograft recipients. All patients were tested for serum HCV RNA using reverse transcription polymerase chain reaction in the 5'-untranslated region (UTR) of the viral genome. HCV RNA positive patients were subjected to genotype analysis using biotinylated type-specific oligonucleotide probes after hybridization with amplified sample material. Eleven of 73 patients showing raised aminotransferase levels underwent hepatic biopsy. RESULTS: Fifteen of 73 (20%) patients were determined anti-HCV positive. Eleven of 73 (15%) showed detectable serum HCV RNA; no viraemic, seronegative patients were identified. Genotyping showed that HCV subtype 2a was dominant (64%), followed by HCV subtypes 1b (27%) and 1a (9%). Six of 11 (54%) HCV RNA patients and 12 of 62 (19%) HCV RNA negative patients showed raised aminotransferase levels (P = 0.03). Liver biopsies showed histological features of chronic hepatitis with mild or moderate degrees of activity. CONCLUSIONS: The prevalence of anti-HCV antibodies and HCV viraemia was 20% and 15% respectively; there was a good association between anti-HCV anti-bodies and HCV viraemia; hepatic enzyme levels were good indicators of ongoing HCV infection; HCV subtype 2a was prevalent; liver histology showed histological characteristics of chronic hepatitis with mild or moderate degrees of activity.

Adult↗
PubMed1996

Survival of diabetic patients on peritoneal dialysis or hemodialysis.

Our objective was to analyze the survival of diabetic patients on renal replacement therapy and to compare their survival on extracorporeal and on peritoneal dialysis. All data regarding diabetic patients admitted to dialysis between 1 January 1983 and 31 December 1993 were collected by means of individual patient questionnaires sent to all of the 44 regional Renal Units (100% answers) of Lombardy, Italy. Cox proportional hazards model, stepwise procedure, was applied in order to select the covariates significantly associated with survival. Age (at baseline), sex, type of diabetes, initial modality of treatment (hemodialysis or peritoneal dialysis), and initial clinical risk factors (malignancies, serious heart disease, vascular disease, cirrhosis of the liver, cachexia) were considered. Descriptive analysis of survival was performed using the Kaplan-Meier technique. The survival of all diabetic patients (895) was 86.5% at one year, 52% at three years, and 34% at five years. The main causes of the 488 deaths of diabetic patients were cardiovascular diseases (56%), cachexia (18%), and infections (11%). The relative death risk of patients on peritoneal dialysis versus those on hemodialysis, after taking into account the main comorbid conditions, did not significantly differ from 1, as estimated by the Cox proportional hazards regression model. Five-year survival of diabetic patients was 34%, and no differences were found between peritoneal dialysis and hemodialysis as far as mortality is concerned.

Adult↗
PubMed1995

1983 to 1992: report on regular dialysis and transplantation in Lombardy.

This 1993 report of the Lombardy Regional Dialysis and Transplant Registry refers to all the data collected between January 1, 1983, and December, 31, 1992, by means of individual patient questionnaires sent to all of Lombardy's 44 renal units (100% replies). The number of patients recorded by the Registry as being alive progressively increased; by the end of 1992, the number was 6,014 (655 patients per million population): 4,770 patients were on dialysis treatment (515 patients per million population, 79.3%) and 1,244 patients (140 patients per million population, 20.7%) had received a kidney graft. The acceptance rate for dialysis increased from 64 per million population in 1983 to 102 per million population in 1992; the increase in the transplant rate was much lower (from 18.7 to 21.3 per million population). The percentage of primary nephropathies in the new patients accepted for dialysis treatment were 22.0% glomerulonephritis, 13.8% interstitial nephritis, 15.2% vascular diseases, 10.1% cystic kidney, and 10.6% diabetes. The use of acetate hemodialysis declined over the 10-year period from 72.4% to 17.5%; that of bicarbonate hemodialysis increased from 8.8% to 50.1% and that of hemodiafiltration increased from 0.2% to 11.1%. The prevalence of hospital hemodialysis was stable, ranging from 55.4% to 52.2%; home hemodialysis decreased from 15.7% to 5.3%, continuous ambulatory peritoneal dialysis increased from 13.3% to 19.6%, and limited care increased from 13.7% to 22.4%. The crude death rate increased from 7.5% in 1983 to 10.5% in 1992. The survival rate (Kaplan-Meier) of all patients on dialysis was 78.8% at 2 years, 62.2% at 4 years, and 40% at 8 years; for transplanted patients, the survival and graft survival rate at 2 years was, respectively, 95% and 86%. The relative death risk of the patients on peritoneal dialysis with respect to those on hemodialysis was 1.419, as estimated by the Cox proportional hazard regression model. The main causes of deaths of patients on dialysis treatment during the year 1992 were cardiovascular diseases (47.0%) and cachexia (19.5%); in transplanted patients, they were cardiovascular diseases (36.6%) and infections (34%). Registries are not only important for planning health care but are also very useful instruments for clinical research.

Adult↗
PubMed1995

Hypertension as a factor in chronic renal insufficiency progression in polycystic kidney disease. The Northern Italian Cooperative Study Group.

The aim of this study was to evaluate the role of blood pressure in the progression of chronic renal failure (CRF) in polycystic kidney disease, by analysing the behaviour of 74 affected patients, out of 456 CRF patients with various underlying nephropathies enrolled in a multicentre, formal prospective trial aimed at clarifying the role of protein restriction in retarding CRF progression. Because no difference was found between the patients on a low protein and those on a controlled protein diet, an inductive analysis was made by separating all of the patients into fast progressive or slowly progressive CRF groups. Hypertensive patients were defined as those with a mean resting blood pressure of more than 107 mmHg; of the 62 polycystic patients who completed the study or who reached an end point, 41 patients were hypertensive and 21 normotensive (10 of whom were pharmacologically controlled). The results of the stratified analysis, taking into account the degree of renal function deterioration and the underlying disease, showed a significant relationship between hypertension and CRF progression only in patients with polycystic kidney disease.

Adolescent↗
PubMed1995

Prognosis of diabetic patients on dialysis: analysis of Lombardy Registry data.

METHODS: This 1993 Lombardy Registry Report refers to all of the data regarding treated diabetics collected between 1 January 1983 and 31 December 1992 by means of individual patient questionnaires sent to all of Lombardy's 44 Renal Units (100% replies). RESULTS: The acceptance rate of diabetics for dialysis increased from 5.6 in 1983 to 10.4 patients per million population in 1992 for a total of 731 patients (379 type I, 352 type II). The yearly percentage of new diabetics increased from 9 to 11%, and the proportion of patients with two or more risk factors increased from 14.7% in 1983-1987 to 22.0% in 1988-1992. The use of peritoneal dialysis declined over the 10-year period from 50% in 1983-1984 to 30% in the last 2 years. The difference in age of the patients on peritoneal and haemodialysis tended to decrease. The survival of all diabetic patients was 82% at 1 year, 48% at 3 years, and 28% at 5 years. The relative death risk of the patients on peritoneal dialysis compared to those on haemodialysis, after taking into account age and the main comorbid conditions (type of diabetes, severe vascular disease, cirrhosis and the generic other risk factors), did not differ significantly from one, as estimated by the Cox proportional hazard regression model (344 events). The main causes of death of these patients were cardiovascular diseases (about 50.0%), cachexia (from 17.2% in 1983/1984 to 22% in 1991/1992), and infection (about 11%). The mean hospitalization rate was higher in diabetics than in patients with standard nephropathies (i.e. in 45-64-year-old patients: 32.8 versus 13.9 days/patient-year). CONCLUSION: Multivariate analysis showed that age, type of diabetes, severe vascular disease, cirrhosis, and the generic other risk factors were significantly related to survival; but diabetic patients without any baseline risk factors also had a poor prognosis and morbidity was very high in absolute terms. Medical care therefore needs to be improved in order to reverse prognostic risk factors and prevent cardiovascular and noncardiovascular events.

Adult↗
PubMed1994

Antibodies to hepatitis C virus (HCV) in chronic renal failure (CRF) patients on conservative therapy: prevalence, risk factors and relationship to liver disease.

There are no data regarding HCV prevalence in CRF patients not requiring dialysis. In order to assess prevalence and risk factors for HCV infection in CRF patients on conservative therapy we tested, by second-generation assays such as Ortho 2 and 4-RIBA, 221 predialysis CRF patients attending our Department. Forty-four (20%) patients were anti-HCV positive. Anti-HCV positivity was related to blood transfusion requirement, past or current elevations of transaminase levels and, to a lesser degree, CRF duration. The prevalence of anti-HCV positivity among CRF patients who were never transfused was about 10 times higher than that of blood donors. Our data show that predialysis CRF patients should be considered a specific risk group for HCV infection; blood transfusion history and duration of CRF are risk factors for acquisition of HCV infection; HCV infection may play a role in the development of liver disease in this clinical setting.

Adult↗
PubMed1993

Hypertension and chronic renal insufficiency: the experience of the Northern Italian Cooperative Study Group.

There is general agreement that hypertension is a prognostic index of the progression of chronic renal insufficiency (CRI), although it remains to be clarified whether this is related to the hypertension per se, or to the underlying disease and the level of CRI. In an attempt to clarify this important point, an inductive analysis was made of the behavior of blood pressure values and their relationship to the progression of CRI in 456 patients (pts) who participated in a multicenter prospective formal randomized trial, designed to compare the effects of a restricted and a controlled protein diet on CRI progression. An analysis was also made (on the population as a whole and by separating the pts into fast progressive and slowly progressive groups) of the type and frequency of the antihypertensive drugs used, the number and type of drugs used in association, and their possible relationship to the progression of CRI. Of the 456 enrolled pts, 406 (89%) were defined as hypertensive at entry (mean blood pressure > 107 mm Hg); 324 out of the 380 pts (85.3%) who completed the 24-month follow-up or reached an end point were treated with antihypertensive drugs. There was a significant difference at entry between the supine blood pressure values of the pts with fast progressive CRI (182 pts), and those of the pts with slowly progressive CRI (198 pts). During the follow-up period, no significant differences were observed between the two groups. There was no difference in the blood pressure levels reached with the different drugs used.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

Controlled trials on low-protein diet: effects on chronic renal insufficiency progression.

The effect of a low-protein diet (LPD) on chronic renal insufficiency (CRI) progression was investigated by reviewing the published studies. Only three of these fulfilled the main methodological criteria of being randomized, prospective, and controlled: those of Rosman, Ihle and Locatelli. These trials involved 811 patients (671 evaluated: 338 on a LPD, 333 as controls) and had a mean follow-up of 29 months (range 18-48), for an estimated total of about 17,335 patient-months. The only trial whose results showed that LPD had a positive effect on chronic renal failure (CRF) progression was Ihle's study, with the lowest weight (6.7%) and involving the most severe CRF; effects limited to the patients with more advanced CRF were found in the Rosman study, with an intermediate weight (41.8%); and little effect, if any, was found in the Locatelli trial, accounting for 51.5% of patient-months, with less severe CRI. In conclusion, analysis of published randomized, prospective, and controlled trials offers little or no support for the hypothesis that a LPD has a clinically significant effect on the early CRI progression, although a very low protein diet seems to postpone the need for dialysis.

Adult↗
PubMed1992

Factors affecting chronic renal failure progression: results from a multicentre trial. The Northern Italian Cooperative Study Group.

In order to evaluate the prognostic factors concerning the rate of progressive deterioration of renal function, we made an inductive analysis of the behaviour of 456 patients in a multicentre, formal prospective trial aimed at clarifying the possible role of protein restriction in retarding the progression of chronic renal insufficiency (CRI). The main clinical and laboratory findings in patients whose plasma creatinine (PCr) levels doubled in comparison with baseline randomization values or who needed dialysis within 24 months after onset of the study were compared with those of the other patients. In addition, independently of the assigned diet, we tested the main variables that might affect CRI progression (sex, systolic and diastolic blood pressure, change in body weight, hematocrit, calcium-phosphate product, proteinuria, protein catabolic rate, total cholesterol and triglycerides). We used multiple regression analyses and also plotted the mean values of these parameters in each patient against an estimate of the deterioration of chronic renal failure based on the difference between the final and the initial reciprocal of the PCr and the creatinine clearance (CCr) levels. A descriptive analysis of the behaviour of PCr in the three CRI groups and in the four underlying diseases groups was made. PCr levels at entry, underlying disease and proteinuria were prognostic factors for CRI progression. The increase in PCr was 0.0102 mg/dl/month in patients with nephrosclerosis, 0.0203 mg/dl/month in interstitial nephropathy, 0.0360 mg/dl/month in glomerulonephritis and 0.0704 mg/dl/month in polycystic kidney disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

[The role of microrhythms and macrorhythms in the emergence of thought in the infant].

Cathexis of time and even more of waiting is considered critical for the development of thought, as S. Freud himself often pointed out. The author discusses the means available to the infant for growing out of the hallucinatory perceptual system and coming to a representational activity which implies a capacity to tolerate the frustration provoked by the waiting. Two distinct interactive processes play a role in the appearance of thought: on one part the macrorythms of repetition involving the interaction partners, mainly in their care-giving activities; on the other part the microrythms with their discontinued rhythms, unsatisfied waiting involving the partners in short sequences, mainly in play activities. The author tentatively demonstrates on the basis of clinical examples and various sources that these seemingly opposed moments give a structure to a unique element of the dyad: the interactive rythm. Rythm is a condition of the capacity to wait and thus of the capacity to think.

Child Development↗