[The low-protein diet in chronic kidney disease: still a valid prescription?]. / La dieta ipoproteica nella nefropatia cronica: una prescrizione ancora oggi valida?

Low-protein diets were originally identified as a therapeutic tool to alleviate symptoms and signs of uremia. Their prescription, however, became common in the 1980s to reduce the rate of progression of chronic kidney disease. Since then, several studies of this nonpharmacological intervention have been published. In particular, the Modification of Diet in Renal Disease (MDRD) study, which is a cornerstone of the nephrology literature, was specifically aimed at verifying the effectiveness of low-protein diets; the results, however, were negative. Therefore, the diet issue progressively disappeared from scientific meetings and journals, and as a consequence also its use in clinical practice has diminished. The aim of this paper is to describe the state of the art of low-protein diets almost 15 years from the publication of the MDRD study.

[Prevalence of chronic kidney disease]. / Prevalenza della malattia renale cronica.

The prevalence of chronic kidney disease (CKD), especially the early stages, is still not exactly known. This is also true for CKD stage 3, when cardiovascular and other major complications generally appear. The NANHES data have shown a steady increase in the prevalence of CKD 3 up to 7.7% in 2004. Chronic kidney disease and renal failure are underdiagnosed all over the world. In Italy, prevalence estimates for stage 3 to 5 CKD are around 4 million yet, less than 30% of these subjects are believed to be followed at nephrology clinics. This means that in Italy for every dialyzed patient there are about 85 individuals with possibly progressive kidney disease, while fewer than five (mainly stage 4 and 5 patients) are actually followed by a nephrologist.

[Low-protein dietary therapy in patients with chronic kidney disease]. / Terapia dietetica ipoproteica del paziente con IRC.

Several prospective studies and meta-analyses including the recent Cochrane meta-analysis have demonstrated that reducing the protein content in the diet delays renal death and the start of dialysis in patients with chronic kidney disease (CKD). Reducing the dietary protein intake offers other benefits such as lowering accumulation of uremic toxins and circulating phosphates and improving symptoms and metabolic derangements. Following the publication of the Cochrane meta-analysis, some of the most renowned experts in Italy on dietary therapy in the CKD patient established a working group within the Italian Society of Nephrology (SIN), the ''Nephrontieres'' project. The current supplement of GIN presents the views of the members of the ''Nephrontieres'' group on a range of issues related to dietary therapy in CKD. A CME program for Italian nephrologists also originated from the collaborative work of the group.

[Low-protein diet in Italy today: the conclusions of the Working Group from the Italian Society of Nephrology]. / La dieta ipoproteica oggi in Italia: le conclusioni del Gruppo di Lavoro SIN.

The high estimated prevalence of chronic kidney disease (CKD) forcefully supports the need for collaboration among nephrologists, cardiologists, diabetologists and general practitioners, to reduce the cardiovascular risk of CKD patients and delay the start of dialysis. Many studies confirm that reducing the dietary intake of proteins improves uremia as well as acid-base and phosphorus disorders without exposing the CKD patient to the risk of malnutrition. The possibility of delaying renal death and the start of dialysis by almost one to two years is also recognized, thanks in part to the antiproteinuric effect of low-protein diets supplemented with keto acids and essential amino acids. Reducing the dietary protein intake delays the start of dialysis independently of the effect of renin-angiotensin system (RAS)-active antihypertensive drugs. Reduction of the dietary protein intake is indicated in patients with a glomerular filtration rate <25 mL/min (CKD stages 4 and 5). Some situations may, however, require an earlier switch to a low-protein diet, e.g., high proteinuria, renal function worsening at more than 5 mL/min/year, diabetes, and metabolic decompensation. If well designed and properly carried out, reduction of the dietary intake of proteins is not associated with low serum albumin levels or malnutrition, and does not affect patients death. Today, highly palatable, high-quality reduced protein preparations are widely available to reduce the protein intake of CKD patients.

[Compliance with low-protein diet in patients with chronic kidney disease]. / Compliance alla dieta nell'insufficienza renale cronica (IRC).

Direct evaluation of the compliance with nutritional therapy is possible only in clinical trials while indirect methods such as self-reporting and interviews are used in clinical practice. Dietary history is the best method to evaluate nutritional habits in clinical practice; the same holds true for the compliance with low-protein diets in patients with chronic kidney disease. Other indexes to assess dietary compliance should be simple and easy to use in the clinical practice. Some of such functional and biological markers are blood urea nitrogen and serum phosphate levels (indirect markers of dietary intake), weight and body mass index (indirect markers of energy intake), and daily urinary excretion of nitrogen and sodium (indirect markers of protein and salt intake). The compliance with a low-protein diet in patients with chronic kidney disease is strongly influenced by psychosocial factors (e.g., satisfaction and comprehension), and thus by the supporting role of the physician and the dietitian, but also by the level of renal function and food characteristics. It must be pointed out that even a protein intake reduction of 0.2 g/kg/day improves blood urea nitrogen, phosphate levels, and acidosis.

Prevalence and correlates of anemia and uncontrolled anemia in chronic hemodialysis patients--the Campania Dialysis Registry.

BACKGROUND: This study investigated prevalence and correlates of anemia and uncontrolled anemia in chronic hemodialysis patients. METHODS: A cross-sectional analysis was performed on registry data for 2,746 chronic (>6 months) hemodialysis patients aged 25-84. Data collection included years of dialysis, hours of dialysis/wk, disease causing hemodialysis, body mass index (BMI), erythropoietin (EPO) treatment, hemoglobin, markers of viral hepatitis, serum albumin, calcium, and phosphorus. RESULTS: Prevalence was 88.7% for anemia (hemoglobin <11 g/100 mL and EPO treatment at any Hb level), 39.4% for uncontrolled anemia (hemoglobin<11 g/100 mL). Gender, years of dialysis, hereditary cystic kidney disease (HCKD), and low BMI (<24 kg/m2) were independent correlates of anemia (P<0.001). Gender, HCKD, low BMI, serum albumin and calcium were independent correlates of uncontrolled anemia (P<0.05). An interaction was found between age (not correlated with anemia and uncontrolled anemia) and the association of gender with uncontrolled anemia (P<0.05). EPO doses were higher in patients with high prevalence of uncontrolled anemia than in patients with low prevalence (i.e., women vs men, other diseases vs HCKD, low vs not-low BMI, P<0.01). Gender, years of dialysis, HCKD, BMI, serum albumin, and calcium were independent correlates of the hemoglobin/EPO dose ratio in patients on EPO treatment (P<0.05). CONCLUSION: Anemia and uncontrolled anemia are more frequent in hemodialysis patients with shortterm dialysis, diseases other than HCKD, low BMI, and female gender. Gender effect was lower in elderly patients. Uncontrolled anemia was also associated with low serum albumin and calcium, suggesting that these parameters are indices of EPO resistance.

Very low protein diet supplemented with ketoanalogs improves blood pressure control in chronic kidney disease.

Blood pressure (BP) is hardly controlled in chronic kidney disease (CKD). We compared the effect of very low protein diet (VLPD) supplemented with ketoanalogs of essential amino acids (0.35 g/kg/day), low protein diet (LPD, 0.60 g/kg/day), and free diet (FD) on BP in patients with CKD stages 4 and 5. Vegetable proteins were higher in VLPD (66%) than in LPD (48%). LPD was prescribed to 110 consecutive patients; after run-in, they were invited to start VLPD. Thirty subjects accepted; 57 decided to continue LPD; 23 refused either diet (FD group). At baseline, protein intake (g/kg/day) was 0.79+/-0.09 in VLPD, 0.78+/-0.11 in LPD, and 1.11+/-0.18 in FD (P<0.0001). After 6 months, protein intake was lower in VLPD than LPD and FD (0.54+/-0.11, 0.78+/-0.10, and 1.04+/-0.21 g/kg/day, respectively; P<0.0001). BP diminished only in VLPD, from 143+/-19/84+/-10 to 128+/-16/78+/-7 mm Hg (P<0.0001), despite reduction of antihypertensive drugs (from 2.6+/-1.1 to 1.8+/-1.2; P<0.001). Urinary urea excretion directly correlated with urinary sodium excretion, which diminished in VLPD (from 181+/-32 to 131+/-36 mEq/day; P<0.001). At multiple regression analysis (R2=0.270, P<0.0001), BP results independently related to urinary sodium excretion (P=0.023) and VLPD prescription (P=0.003), but not to the level of protein intake. Thus, in moderate to advanced CKD, VLPD has an antihypertensive effect likely due to reduction of salt intake, type of proteins, and ketoanalogs supplementation, independent of actual protein intake.

Fourteen years of hemodialysis with a central venous catheter: mechanical long-term complications.

The ideal dialysis access ensures adequate blood flow for dialysis, has a long life, and is associated with a low complication rate. Although no current type of access fulfills all these criteria, the native arteriovenous fistula (AVF) is close to doing so. Unfortunately, various kinds of vascular access (VA) are becoming more and more necessary to enable hemodialysis (HD). The central venous catheter (CVC), which is associated with higher morbidity and mortality, could be the only viable option to maintain permanent VA. We report an unusual complication in a patient, a 74-year-old female, who had been undergoing HD via a CVC for 14 yrs. A polyurethane CVC with a double lumen was inserted into the right internal jugular vein because an AVF was not feasible, and a polytetrafluoroethylene (PTFE) prosthesis was obstructed. In 2003, the CVC was removed due to stenosis and occlusion of the superior vena cava. A new CVC, also made of polyurethane and with a double lumen, was inserted into the left femoral vein. In January 2005, the patient reported a small rupture of about 3-4 mm located under the cuff of the CVC. For this reason, the left femoral vein had to be used, replacing the Optiflow one with a 40-cm long Tesio CVC, and the second catheter was inserted into the right femoral artery by conventional surgery. After 10 months, the patient returned once more, after the CVC in the left femoral vein had been removed because of malfunction and that the at-tempts to cannulate the same vein again had failed. Currently, two 70-cm long Tesio catheters implanted in the right femoral vein (whose tips almost reach the diaphragm) are used for dialysis sessions. The number of CVC implants has progressively increased amongst HD patients who are elderly, diabetic or who have been on long-term HD. The patient described in this case report is currently using a 70-cm long double Tesio catheter (single Tesio CVC in SPI silicon) placed in the right femoral vein. She has resumed therapy with dicumarol anticoagulants, maintaining INR within the 2.5-3.5 range. In conclusion, both the increase in the use of venous catheters for HD and in the survival of dialysis patients contribute towards the observation of rare complications associated with CVC use.

[Bioelectrical analysis in uremic patients]. / La bioimpedenza nella clinica del paziente uremico.

Bioelectrical analysis (BIA) is an easy, repeatable, low cost, operator-independent method. BIA obtains two different goals, i.e. body water content evaluation, by the RXc Graph or the BIVA Z score and morbidity and mortality predictions by the phase angle. Therefore, BIA can be considered as part of the clinical examination for the evaluation of both hydration and nutritional status.

Management of hypertension in chronic kidney disease: the Italian multicentric study.

BACKGROUND: Guidelines have indicated the achievement of blood pressure target (BP <130/80 mmHg) as a priority in the conservative treatment of chronic kidney disease (CKD), but the current implementation of these recommendations in clinical practice is unknown. METHODS: We assessed control rates, treatment and clinical correlates of hypertension in 1201 adult non-dialyzed CKD patients followed up by a nephrologist for at least 6 months. RESULTS: Estimated glomerular filtration rate (GFR) was 32 (SD 15) mL/min/1.73 m2. BP target was not achieved in 88% of patients (95% confidence interval (95% CI): 86-90%). In 84% of patients, BP levels were also above the target at the first visit to the nephrology unit 4.5 yrs previously. The risk of not achieving BP target during the nephro-logy follow-up was associated with older age (odds ratio (OR): 1.24, 95% CI 1.06-1.45, p=0.008), diabetes (OR: 2.25, 95% CI 1.20-4.20, p=0.011), and the duration of hypertension (OR: 1.13, 95% CI 1.02-1.24, p=0.016). Among patients with uncontrolled BP, about 70% received multidrug antihypertensive therapy including renin-angiotensin system (RAS) inhibitors; conversely, diuretic treatment was prescribed in a minority of patients (37%), and at insufficient doses in half the cases, despite the insufficient implementation of a low salt diet (18%). CONCLUSIONS: BP target was not reached in most CKD patients routinely seen in the renal clinics. The main barrier to guideline implementation is possibly the inadequate treatment of extracellular volume expansion despite the large prevalence of factors, such as older age and diabetes, which further enhance the intrinsic BP salt sensitivity of CKD.

The prediction of single-frequency BIA variables from individual characteristics.

To define whether reference values for bioimpedance analysis (BIA) can be predicted in healthy individuals, individual characteristics and BIA variables (resistance index=height(2)/parallel resistance and reactance index= height(2)/parallel reactance) were evaluated in non-obese healthy individuals: 863 men and 769 women with an age range 20-70 years and body mass index (BMI) 19.0-29.9 kg/m(2). The following predictive equations were obtained using multiple regression analysis:Resistance index (cm(2)/ohm)Males 21.06 + 0.087xage + 1.091xweight -1.801xBMI,Females 20.35 + 0.037xage + 0.878xweight - 1.343xBMIReactance index (cm(2)/ohm)Males 0.57 + 0.117xweight - 0.096xBMIFemales 1.42 + 0.078xweight - 0.075xBMIIn conclusion, reference BIA values seem to be reasonably predicted based on individual characteristics.

[Usefulness of directional power Doppler sonography in the ultrasound-guided percutaneous native kidney biopsy]. / Utilita' dell'Eco Power Doppler direzionale nella biopsia transcutanea su rene nativo.

BACKGROUND: The study was aimed to analyze the pattern of bleeding throughout the kidney tissue after renal biopsy and evaluate its relationship with the onset of renal biopsy side effects by using directional power-Doppler sonography. PATIENTS: Eighty-five consecutive subjects with clinical evidence of renal disease underwent to percutaneous renal biopsy using directional power Doppler sonography. In each patient, the pattern of kidney hemorrhage immediately after the renal biopsy was evaluated. RESULTS: Fifty-seven patients, representing 67% of all biopsies performed, evidenced renal bleeding lasting 5.3+/-5.7 min; fifty-five patients, representing 65% of all biopsies, developed a post biopsy hematoma (x = 2.9+/-2.0 cm); 36% of patients developed a perirenal hematoma (x = 1.8+/-2.1 cm). A subcapsular hematoma was experienced by 45% of patients (x = 2.7+/-1.1 cm); 16% of these patients had a combined perirenal-subcapsular hematoma; 5% of hematomas were larger than 5 cm. Hematoma dimensions were related to the length of bleeding (r = 0.6331; p < 0.0001). Hemoglobin and hematocrit levels significantly reduced from 12.7+/-2.3 g/dL to 11.7+/-2.3 g/dL (-7%, p < 0.0001) and 37.6+/-6.5% to 35.4+/-6.5% (-6%, p < 0.0001) respectively, and such variations were related to the hematoma size (Delta Hb: r = -0.5171; p < 0.0001; Delta Htc: r = -0.3465; p < 0.0001). CONCLUSIONS: This study demonstrates that directional power Doppler sonography allows medical personnel to clearly evidence all renal biopsy-related side effects and identify, through the evaluation of renal bleeding immediately after the kidney biopsy, those patients who will develop renal hematomas.

[Regional epidemiology of chronic nephropathies: referral to nephrologist and initiation of dialysis]. / Epidemiologia regionale/locale delle nefropatie croniche: profili di "referral" ambulatoriale e inizio dialisi.

BACKGROUND: The epidemiology of pre-dialysis chronic nephropathies (CN) in well-defined contexts is essential to prevent delays in delivering appropriate care. METHODS: The registration of consecutive patients in seven out-patient and four in-patient dialysis centers of Basilicata (2001) formed a retrospective study on clinical charts and dialysis registers integrated with ad hoc data. RESULTS: Newly observed outpatients (I) numbered 328; prevalent patients (P) numbered 343. The age and gender of both I and P patients was similar (males: 60%, age media: 67 yr). In 316 I patients with creatinine (mean Cr: 2.3 mg/dL), the mean filtration rate (GFR) was 40.9 mL/min/1.73 m2: 13.6% were in advanced stage (S5) of GFR (<15 mL/min), 23.4% in S4/severe (15-29), 45.6% in S3/moderate (30-59), 10.8% in S2/mild (60-89), and 6.6% in S1 (>90). When compared to I patients, P patients had a mean GFR of 35.0 mL/min; S4+S5 was 48% (vs. 37%); hypertension 68% (vs. 58%); vasculopathies 15% (vs. 10%); coronary disease 10% (vs. 4%); erythropoietin 13% (vs. 7%); and low-protein diet 34% (vs. 20%) (p<0.01). Of 316 I patients, 117 in S5+S4 ('late referral' 37%) had a (mean) GFR of 18.4 mL/min, Cr 3.7 mg/dL, and were aged 70 yrs (vs. 64 yrs for 'early referral'). Of 53 new patients on dialysis, 26 (49%) were seen for the first time <6 months prior to starting (mean age: 71 yr vs. 62; female 58% vs. 26%; complications 50% vs. 17%). CONCLUSIONS: In this population, age-related factors are associated with late referral. Although sociodemographic variables depend on local contexts, these results are consistent with similar international studies. Social and cultural factors may influence physicians to postpone referring patients to a nephrologist, independently of clinical conditions.

[Daily nutrient intake in hemodialysis]. / Variabilità dell'introito giornaliero di nutrienti nei pazienti emodializzati.

BACKGROUND: Although there is a higher nutrient requirement, food intake in haemodialysis patients is often inadequate. Protein nitrogen appearance (PNA) indirectly estimates the mean protein intake during the short interdialysis period, but it does not measure the daily nutrient intake, which is generally unknown. We carried out a longitudinal study aimed at estimating the daily nutrient intake and its relationship with the nutritional status of haemodialysis patients. METHODS: We selected 28 haemodialysis patients with adequate nutritional status and no evidence of risk-factor for malnutrition. Patients were treated with biocompatible membranes, low-flux and high bicarbonate dialysis, Kt/V > 1.2, PNA > 1.1 g/kg/day and erythropoietin. We measured every four months daily PNA, protein and calorie intake (DPI, DCI) as well as weight gain (WG) during an entire week for one-year. The nutritional status was assessed by biochemical and BIA markers. RESULTS: Twenty seven subjects (8 F, 19 M; age 57.1 +- 2.7 yeas; dialysis age 105 +- 13 months) completed the trial. The mean interdialytic PNA did not change in both long- and short-interdialysis periods, resulting in the "normal" range (> 1.1 g/kg/day); however, daily levels of protein and calorie intake were significantly reduced on the third day during the long interdialysis interval. Eight patients showed time-averaged values of DPI and DCI lower than 0.8 g/kg/day and 25 Kcal/kg/day, respectively, on the third day (LOW group), values that were associated with similar changes in WG. Such a highly reduced nutrient intake during the third interdialysis day was associated with a normal PNA value (1.23 +- 0.05 g/kg/day vs 1.30 +- 0.06 in CON, NS) when measured during the short interdialysis period (S), just as it is in clinical practice; in contrast, when the PNA value was measured during the long interdialysis period it was found to be significantly reduced (1.07 +- 0.08 g/kg/day vs 1.37 +- 0.06 in CON, p < 0.05 and vs S, p < 0.05). During the study, the body weight progressively decreased from 68.0 +- 5.5 to 65.8 +- 5.9 kg (p < 0.05) in the LOW group, due to the decrease in lean body mass, as suggested by the reduction in serum creatinine (9.2 +- 1.1 vs 8.1 +- 0.7 mg/dL, p < 0.05), creatinine generation (835 +- 155 vs 723 +- 106 mg/die, p < 0.05) and serum albumin (3.96 +- 0.07 vs 3.66 +- 0.06 g/dL, p < 0.05). Moreover, reactance and phase angle declined in the LOW group (from 54 +- 4 to 44 +- 3 ohms, p < 0.05 and 5.5 +- 0.3 to 4.5 +- 0.3 degrees, p < 0.05, respectively). At the end of the study the nutritional status in the LOW group was reduced as compared to the CON group. CONCLUSIONS: In stable, well-nourished haemodialysis patients, in absence of known risk factors for malnutrition, the daily nutrient intake is variable and progressively reduce during the interdialytic interval. The measurement of interdialytic PNA, as is done in clinical practice, does not enable the discovery of such abnormal eating behaviour; the low daily nutrient intake, on the contrary, can be evidenced by the daily measurement of either PNA or weight gain, and it can also be inferred by the reduced PNA during the long interdialytic period. Finally, the persistent reduction in nutrient intake below the threshold of 0.8 g/kg/day of proteins and 25 Kcal/kg/day one day a week, is capable of inducing body protein wasting and moderate impairment of the nutritional status.

[Can anemia be corrected in hemodialysis patients with thalassaemia minor? ]. / La correzione dell'anemia nei pazienti in emodialisi con Talassemia minor e' possibile?

BACKGROUND: Anemia is an important negative prognostic factor for dialysis patients, whose correction reduces hospitalisation and mortality. Besides, the presence of the thalassaemia minor (Thal-m) in haemodialysed patients causes erythropoietin resistance and more serious anemia. The goal of this study is the correction of anemia (Hb >11 g/dL) in haemodialysed Thal-m patients. MATERIALS AND METHODS: Multicentric, prospective and controlled 12-month study for the correction of anemia (up to values ranging from 11 to 12 g/dL) followed by a 12-month observation period. Ten Thal-m patients with inadequate anemia correction were studied after therapy with rHuEPO. Their age at the beginning of the study was 62.8+/-4 years while their dialytic age was 89+/-20 months. RESULTS: During the study we observed no changes in dry weight (p=NS), no increase in interdialytic weight (p=NS), cardiac frequency (p=NS), serum albumin (p=NS), serum aluminium (p=NS), PTH (p=NS), URR (p=NS), flow FAV (p=NS), TSAT (p=NS) and ferritin (p=NS) (maintained at their optimal values by means of intravenous therapy with trivalent iron. The hypotensive therapy (1.6 drug/patient/year) required no modifications during the 24-month study. The rHuEPO dose varied from 200.3+/-94.3 to 286.6+/-116.2, 317.0+/-119.5, 446.9+/-142.3, and 407.0+/-130.5 U/kg/wk (p < 0.0001 vs. initial value) (from the start to the 3rd, 6th, 9th and 12th month, respectively). The dose was subsequently reduced to 385.2+/-119.7 U/kg/wk at 15 months (p < 0.0001 vs. initial value) and remained unchanged until the end of the study. Simultaneously, the Hb values at corresponding times were 9.2+/-0.9, 9.4+/-1.1, 10.2+/-1.4, 10.9+/-1.5, 11.2+/-1.4 and 11.0+/-1.4 (p=0.002 vs. initial value). The correction of anemia produced progressive reduction in cardiac mass from 141+/-12 to 120+/-10 and 110+/-8 g/mq at the beginning, 12th month and 24th month (p < 0.0001), respectively. During the study the hospitalisation time was 4.3+/-1.2 day/patient/year during the 3-month run-in period, 3.4+/-1.4 day/patient/year during the first year, and 3.1+/-1.1 day/patient/year during the second year (p=0.098). CONCLUSIONS: In conclusion we can say that the question of Thal-m in dialysis patients cannot be ignored or underestimated. The rHuEPO dosage in these patients must be reassessed (a dose of 450 U/kg/wk corresponding to approximately 60,000 units/week is acceptable and does not produce an increase in side effects if the correction is done gradually); moreover, other factors responsible for EPO-resistance must be eliminated (hyperthyroidism, aluminium intoxication, iron overloaded or deficiency).

[Acute and chronic effects of standard hemodialysis and soft hemodiafiltration on interdialytic serum phosphate levels]. / Effetti acuti e cronici della emodialisi standard e dell'emodiafiltrazione-soft sui livelli interdialitici della fosforemia.

INTRODUCTION: The dialytic management of hyper-phosphoremia, which is inadequate because of insufficient intra-dialytic removal of phosphate (P), is further limited by PDR-P, i.e. the significant increase in serum P levels during the early postdialytic period. Patients and methods. To investigate the effects of enhanced P removal by haemodiafiltration on the inter-dialytic phosphoremia, we studied 12 uremic patients that were switched, with cross-over randomised modality, to a single session of standard hemodialysis (HD) and hemodiafiltration (HDF) (Acute Study). Blood samples were obtained before the treatment, at the end (T0), after 30, 60, 90 and 120 minutes, and at 24, 48 and 68 hours. During both dialytic treatments the whole effluent dialysate was collected to evaluate the intradialytic removal of P. Thereafter, patients were randomised to receive either HD or HDF for three months, in the presence of constantly similar Kt/V, food intake and dose of phosphate binder (Chronic Study). RESULTS: Acute Study. Compared to HD, P removal in HDF was about 44% greater in the presence of identical predialytic P levels (6.0+/-0.2 and 5.9+/-0.4 mg/dl) and Kt/V (1.35+/-0.06 and 1.34+/-0.05); however, the inter-dialytic decline of serum P levels did not differ (-50+/-3% versus -42+/-3%, p=0.098). In HDF, PDR-P was faster (30 min versus 90 min) and better (at T120: +69+/-6% versus +31+/-4%, p<0.001). The higher P levels were maintained throughout the inter-dialytic period whereas Ca x P changed in parallel. Chronic Study. During the three months, pre-dialytic serum P diminished in HDF (from 5.8+/-0.2 to 4.4+/-0.3 mg/dl, p<0.05), while it remained unchanged in HD. A similar pattern of changes was detected in Ca x P. CONCLUSIONS: Enhancement of P removal, acutely amplifies the extent of PDR-P, but allows better control of Ca-P homeostasis in the medium term. This effect is likely to be dependent on the enhanced mobilisation of phosphate from a deep compartment.

[Thalassaemia minor: national survey of uraemic patients under substitutive treatment]. / Talassemia minor: indagine nazionale dei pazienti uremici in trattamento sostitutivo.

BACKGROUND: The incidence of thalassaemia minor in end-stage renal disease patients is similar to that of the general population. Both these conditions are characterized by anaemia, but the underlying pathophysiology is quite different. Current literature lacks an adequate clinical survey of haemodialysis patients with thalassaemia minor. METHODS: The prevalence of thalassaemia minor (thal-m) in haemodialysis patients was assessed by a national survey collecting general information as well as clinical and haematological parameters. Data were also collected on the use of recombinant erythropoietin in these subjects. A dedicated questionnaire was sent to all Italian dialysis units. RESULTS: Only 116/705 dialysis units returned the questionnaire (16.4%): 33 units did not have any patients affected by thalassaemia minor. No response was obtained from six Italian regions whereas ten regions returned only partial answers. The response from four regions was satisfactory (20%) while the completed questionnaire was returned by all units in only two small regions. A total of 7731 ESRD patients were collected, 240 (3.1%) were also affected by thal-m, 142 males and 98 females. In the four regions with the highest response rates, Calabria 45%, Puglia 65%, Basilicata and Molise 100%, the prevalence of thal-m were 3.68%, 4.56%, 3.3% and 1%, respectively. A total of 3623 uraemic patients (47% of all enrolled subjects) were collected from these four regions. Here is the patient geographic distribution: northern Italy 2.16% (response rate of 9.44%); central Italy 1.69% (response rate of 7.64%), southern Italy 3.77% (response rate of 29.46%). The age range of thal-m patients was 17 to 90 years, the time spent on dialysis was between 3 and 384 months, the body weight was between 35 and 93 kg, the Hb value was between 6.2 and 13.6 g/dl, and the Htc value was between 19 and 44%. A total of 230 thal-m patients were on haemodialysis while 10 patients were on peritoneal dialysis (4.2%). The mean haemoglobin level for the thal-m group was 9.8+/-1.4 g/dl and for the control group the value was 11.4+/-1.4 g/dl (p < 0.0001). The use of rhEPO was on the average 7659+/-6256 u/wk for the thal-m and 4378+/-4435 u/wk for the control group (p < 0.0001). The bodyweight was 129+/-105 u/kg/wk (range 0-370). Finally, 17.9% of the thal-m patient did not use rhEPO, their Hb value was 10.66+/-1.67 g/dl (range 8.2-13). No patient went over 30 thousand units and only 4 had such dosage in therapy. The 12.1% thal-m patients with Hb < 10 g/dl did not use rhEPO. The need for rhEPO per gram of Hb was 796+/-722 u/wk in thal-m patients and 416+/-449 U/wk in control patients (p < 0.0001). Uraemic anaemia was corrected with 4.8 million red blood cells in the control group and with about 7.7 million red blood cells in the thal-m group. CONCLUSIONS: Data from this national survey, although incomplete, show that rHuEpo is less effective in these patients and its use does not seems to be correct. It is important to emphasise that recent Guidelines do not recommend neither a specific treatment for these patients nor the use of r-HuEpo. However, it should also be underscored that most thal-m patients do not reach the target Hb level suggested by the National Guidelines for the general population in chronic dialysis.

Abnormalities of bioimpedance measures in overweight and obese hemodialyzed patients.

BACKGROUND: The body composition in overweight and obese hemodialyzed patients (HD) remains ill-defined. This study evaluates in HD patients the influence of body size, as indicated by body mass index (BMI, kg/m(2)), on body composition by measuring bioimpedance analysis (BIA)-derived variables (phase angle (PA), fat-free mass (FFM) and body cell mass (BCM). METHODS: We studied 50 Caucasian patients (mean age 62.8+/-9.2 y) on standard bicarbonate hemodialysis for at least 12 months who regularly achieved dry weight in post-HD, received similar dialysis doses and were free from inflammation/infection. Thirty-eight gender- and age-matched healthy subjects were included as controls (CON). Both HD and CON were divided into three groups on the basis of their BMI(kg/m2) 18.5-24.9, normal-weight (NW); 25-29.9, overweight (OW); and > or =30, obese (OB). In HD patients, BIA was performed 30 min after the end of dialysis. RESULTS: Seven patients were obese (12%) while 16 were overweight (32%); in CON, 12 were obese (31%) and 12 overweight (31%). BIA-measured extracellular water was comparable in all groups. PA, which was similar in normal-weight HD and CON (6.2+/-0.9 degrees and 6.3+/-0.8 degrees ), decreased in OW- and OB-HD patients (5.3+/-1.0 degrees and 5.2+/-0.6 degrees, respectively; P<0.05 vs NW-HD) while it was unchanged in OW- and OB-CON (6.1+/-0.8 degrees and 5.9+/-0.5 degrees, P<0.05 vs respective HD groups). In OW and OB patients, the lower PA values were coupled with a major reduction of BIA-derived percentage BCM and FFM (P<0.05 vs NW-HD, and vs OW- and OB-CON). In patients, PA and BCM correlated with anthropometry-measured FFM. Of note, serum albumin and protein catabolic rate were significantly reduced in OB patients. CONCLUSION: In overweight and obese HD patients, BIA-derived FFM, BCM and PA are significantly lower with respect to normal-weight patients and BMI-matched controls. These abnormalities of body composition are coupled with reduction of anthropometric measures of lean mass and a decrease of protein intake that, however, becomes significant only in the obese. We therefore suggest that overweight and obese HD patients are at risk of protein malnutrition in spite of excessive energy intake. BIA may be considered as a useful diagnostic tool to detect such a condition early.

Successful use of central venous catheter as permanent hemodialysis access: 84-month follow-Up in lucania.

Cuffed tunneled venous access catheters are commonly used for temporary and permanent access in hemodialysis (HD) patients. These catheters serve an essential role in providing permanent access in subjects in whom all other access options have been exhausted. The predominant complications are catheter thrombosis, catheter fibrin sheating and infection. The aim of this study was to evaluate long-term survival and complications of permanent venous catheters (PVC) placed for the purpose of HD during the period from January 1992 to December 1998, at the Dialysis Units of Lucania (a southern Italian region). A total of 98 PVC were placed in 88 patients during this period. The catheters used were of three types: (a) 72 VasCath Soft Cell catheters (Bard Instrument Company, Toronto, Ont., Canada); (b) 22 PermCath catheters (Quinton Instrument Company, Seattle, Wash., USA), and (c) 4 Tesio catheters (Bellco SpA, Mirandola, Italy). Survival curves of catheters were calculated using the Kaplan-Meier product-limit estimator. The patient survival was 60% at the 78th month. Actually, 52 patients (27 males, 25 females) are still alive: 15 (26.9%) of these patients have diabetes mellitus and 1 has been transplanted. The actuarial survival rate of PVC was 89% in the whole population studied and 82% in subjects alive after 84 months. Twenty-five patients (28.4%) had PVC as the first reliable vascular access. Long-term complications occurred 27 times (1 episode every 44.81 month/patient) as: breakage (3.1%); thrombosis (10.2%); displacement (2.0%); subcutaneous tunnel bleeding (3.1%); inadequate blood flow (7.1%), and infection (10.2%). In conclusion, our data confirm that PVC might represent an effective long-term blood access route for HD. Again, PVC are getting the access of choice for selected patients (i.e., older subjects with cardiovascular diseases and cancer patients) and are enjoying a dramatic increase in use for subjects who are terrified of repetitive venopuncture.