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Daniela Bergamo

Publications and source records attributed to Daniela Bergamo.

11 recordsLinked to original sources
PubMed2005

Long-term, low-dose, intravenous vitamin C leads to plasma calcium oxalate supersaturation in hemodialysis patients.

BACKGROUND: Ascorbate supplementation for patients on regular dialysis treatment (RDT) is advised to obviate deficiency and improve epoetin response in those with functional iron deficiency. However, clear-cut safety concerns regarding hyperoxalemia are still poorly understood. This study tries to establish safety/efficacy profiles of ascorbate and oxalate during long-term intravenous ascorbate supplementation. METHODS: A prospective study was performed in 30 patients on RDT showing ascorbate deficiency (plasma ascorbate < 2.6 mg/L [<15 micromol/L]): 18 patients were administered intravenous ascorbate during 18 months (250 mg/wk, subsequently increased to 500 mg), and 12 patients were taken as reference untreated cases. Plasma ascorbate and oxalate assays and dialytic balance determinations were performed (ion chromatography and reverse-phase high-performance liquid chromatography, respectively) at baseline, during treatment, and 12 months after withdrawal. RESULTS: Plasma ascorbate levels increased dose dependently with supplementation (1.6 +/- 0.8 mg/L [9.1 +/- 4.6 mumol/L] at baseline, 2.8 +/- 1.8 mg/L [15.9 +/- 10.1 micromol/L]) with 250 mg of ascorbate, and 6.6 +/- 2.8 mg/L [37.5 +/- 16.0 micromol/L] with 500 mg/wk of ascorbate), but only normalized with greater dosages for several months in 94% of patients. Baseline plasma oxalate levels increased from 3.2 +/- 0.8 mg/L (35.8 +/- 8.8 micromol/L) to 3.6 +/- 0.8 mg/L (39.5 +/- 9.1 micromol/L) and 4.5 +/- 0.9 mg/L (50.3 +/- 10.4 micromol/L) with 250 and 500 mg, respectively ( P < 0.001). The calcium oxalate saturation threshold was exceeded by 7 of 18 patients (40%) during 6 months therapy with 500 mg/wk. Ascorbate dialysis removal increased from 37.8 +/- 23.2 mg (215 +/- 132 micromol) to 99.6 +/- 51.7 mg (566 +/- 294 micromol) during supplementation (P < 0.001), with corresponding increases in oxalate removal from 82.5 +/- 33.2 mg (917 +/- 369 micromol) to 111.2 +/- 32.6 mg/L (1,236 +/- 362 micromol; P < 0.01). Withdrawal reverted plasma levels and dialysis removal to initial values. Values for untreated patients did not change during 1 year of follow-up. CONCLUSION: Patients on RDT may resolve ascorbate deficiency with intravenous supplementation of 500 mg/wk, but this implies a significant risk for oxalate supersaturation. Oxalate measurements are strongly recommended during long-term ascorbate therapy.

Adult↗
PubMed2004

Low-dose continuous iron therapy leads to a positive iron balance and decreased serum transferrin levels in chronic haemodialysis patients.

BACKGROUND: Iron balance is critical for adequate erythropoiesis, but its optimal therapeutic regimen remains to be defined. Continuous maintenance therapy with iron has been proposed for dialysis patients on recombinant human erythropoietin (rHuEpo) in the hope that the regimen is adequate and safe. METHODS: We determined serum ferritin, transferrin, transferrin saturation (TSAT), serum transferrin receptors, albumin and C-reactive protein (CRP) in a 3-year prospective study in 30 chronic haemodialysis patients on dialysis treatment for 132+/-111 months (18 males, 12 females; mean age 56+/-14 years). Beginning in the year 2000, they regularly received low-dose maintenance iron supplementation (i.v. iron gluconate 31.25 mg/week) for 12 months (Period 1 or first treatment phase), followed by a 6-month withdrawal (Period 2 or stop phase) and then by continuous maintenance iron therapy (i.v. iron gluconate 31.25 mg/week) for another 9 months (Period 3 or re-challenge phase). RESULTS: A significant increase in serum ferritin and TSAT was observed, with values exceeding 500 ng/ml and 50% in 10/30 (33%) and 7/30 (23%) of subjects, respectively, in Period 1, and in 11 and 5% in Period 3. A significant decrease in serum transferrin was documented during Period 1, followed by an increase in Period 2 and a decrease in Period 3. Serum albumin remained stable. Serum transferrin was always negatively correlated with ferritin (r = -0.41, P<0.001) and weakly correlated with serum transferrin receptors (r = 0.178, P<0.05), but was not correlated with serum albumin or CRP. Regression equations based on pre-treatment serum ferritin values were developed for predicting the value of serum ferritin at any time following the beginning of continuous iron supplementation. They fitted a linear relationship for males (y = 81 + 21.5 x time) and for females (y = 65 + 22 x time). Percentile charts for quantitative tracking of serum ferritin increases and decreases in patients have also been developed from values measured at different times. These charts show box-plot distributions of expected ferritin against time. CONCLUSIONS: Even continuous low-dose maintenance iron therapy, with only 31.25 mg weekly over 1 year, cannot prevent the risk of iron overload in patients with moderate anaemia. Furthermore, this treatment is responsible for decreases in serum transferrin, unrelated to changes in serum albumin, possibly of concern for hypo-transferrinaemia as an independent risk factor for iron toxicity.

Aged↗
PubMed2004

Validation of serum ferritin values by magnetic susceptometry in predicting iron overload in dialysis patients.

BACKGROUND: Guidelines for treating anemia in dialysis patients accept, as high-end range of serum ferritin useful to optimize erythropoietin therapy, values high as 500 to 900 microg/L, on the hypothesis that ferritin might be not representative of iron overload. METHODS: A superconducting quantum interference device (SQUID) was used to make direct noninvasive magnetic measurements of nonheme hepatic iron content in 40 dialysis patients treated with intravenous iron, and liver iron content was compared with biochemical markers of iron status. RESULTS: Only 12/40 (30%) patients showed normal hepatic iron content (SQUID <400 microg/g), while 32.5% had mild (400 to 1000 microg/g) and 37.5% severe (>1000 microg/g) iron overload, although 28/40 patients (70%) had serum ferritin below 500 microg/L. Among many parameters, hepatic iron content was only correlated with ferritin (r= 0.324, P= 0.04). The receiver operating characteristic (ROC) analysis showed the best specificity/sensitivity ratio to identify iron overload for ferritin >340 microg/L (W = 0.716). Multivariate logistic regression analysis demonstrated that an increase in serum ferritin of 100 microg/L and female gender were independent variables associated with moderate to severe hepatic iron overload: OR 1.71 (95% CI 1.10 to 2.67) and OR 10.68 (95% CI 1.81 to 63.15), respectively. CONCLUSION: Hepatic iron overload is frequent in dialysis patients with ferritin below currently proposed high-end ranges, and the diagnostic power of ferritin in indicating true iron stores is better than presumed. Safety concerns should prompt a reevaluation of acceptable iron parameters, focusing on potential gender-specific differences, to avoid potentially harmful iron overload in a majority of dialysis patients, mainly females.

Adult↗
PubMedDate not supplied

Teenagers' point of view on living donor kidney transplantation: Cinderella or princess?

UNLABELLED: Living kidney donation is an important clinical option, encountering different fortunes in the world. AIM: To analyse the opinions of a large subset of older teenagers attending high school (7999 students, median age 18) on different aspects of living kidney transplantation. METHODS: Analysis of semistructured questionnaires submitted within an educational campaign on dialysis and transplantation in the high schools of Torino and its county (about 2,000,000 inhabitants). RESULTS: Over 90% of the students had already heard of transplantation, mainly via television (88.4% county, 84.5% city). 80% would donate a kidney to a family member (3.5% wouldn't, 16.5% uncertain); answers were correlated with sex (females more than males p<0.0001), school type (istituti tecnici versus licei p=0.007), interest (yes versus other p<0.0001). A lower percent of individuals would receive a kidney (58.4% county, 59.4% city), only 10% would ask for donation. Over 40% of students consider legally buying a kidney a patient's right, only 26.6% would discourage this choice. The answers were correlated with the reverse pattern as for non-mercenary donation with type of school (licei more than istituti tecnici: p<0.0001), sex (males versus females p<0.0001), interest (not versus yes: p=0.002). CONCLUSIONS: Teenagers are favourable towards all forms of living kidney donation. The lower prevalence of positive answers on acceptance versus donation suggests that fears of endangering the donor's health may be one of the causes for a low living donation rate in our setting. The mixed answers on mercenary donation suggest discussing this complex issue in future educational programs.

Adolescent↗
PubMedDate not supplied

Guidelines audit may overcome disparities in health care: experience of an Italian region.

BACKGROUND: A clinical audit is used to verify the application of evidence-based clinical guidelines. Our regional section of the Italian Society of Nephrology was the first to establish a region-based program of clinical audits of compliance with guidelines for treating osteodystrophy and anemia of patients on chronic dialysis. This study summarizes the main results of the 2 audits of the Piemonte region. METHODS: Structured questionnaires were sent twice to all of the 22 dialysis centers of Piemonte and to the Center of Valle D'Aosta for an Audit on Osteodystrophy (in 2000 and 2004) and for the Audit on Anemia (2003). The questionnaires were meant to evaluate the clinical schedule of treatment relative to calcium-phosphate balance and anemia in dialysis patients. RESULTS: All centers responded, showing low levels of agreement with the targets of Italian guidelines. In sum, in 2000 only 27% of centers had more than 70% of patients with serum phosphate <5.5 mg/dL, but that rate had increased to 33% in 2004. Only 35% (in 2000) and 40% (in 2004) of the centers had more than 90% of patients with Kt/V >1.2. The Audit on Anemia showed a median of 42% of patients with hemoglobin between 11 and 12 g/dL, and only 2 centers had more than 70% of patients above this target. CONCLUSIONS: The first result of our pioneering experience was that we found that compliance with minimal levels of care was still inadequate, with regard to hyperphosphatemia, dialysis adequacy and anemia. Nevertheless, the 2nd Audit on Osteodystrophy showed a relative improvement in the results. But, most importantly, this open regional report has encouraged comparisons, and motivated centers to adopt a strategy of understanding, addressing and correcting inadequate levels of care, and furthermore increased satisfaction with the care being offered.

Aged↗