On-line predilution hemofiltration versus ultrapure high-flux hemodialysis: a multicenter prospective study in 23 patients

The aims of the present prospective multicenter study were to assess the clinical tolerance and well being, the correlation between nPCr and Kt/V and the pretreatment β2-microglobulin level in patients sequentially treated with high-flux dialysis with ultrapure bicarbonate hemodialysis (HD; phase I) and predilution hemofiltration (HF) with on-line prepared bicarbonate substitution fluid (phase II). The same monitor (Gambro AK 100 ULTRA) and membrane (polyamide) were used. Twenty-three patients, all in a stable clinical condition, entered the study. The treatment was targeted to an equilibrated Kt/V (eqKt/V) of 1.4 for HD and 1.0 for HF. No mortality or relevant morbidity were observed. The number of hypotensive episodes was 1.78 ± 2.8 per patient and month during HD vs. 1.17 ± 3.1 during HF (p = 0.003) and the number of the hypertensive episodes 1.28 ± 2.8 during HD vs. 0.42 ± 0.8 during HF (p = 0.04). Incidences of arrhythmia, muscular cramps and headache were significantly less frequent during HF. Interdialytic cramps, arthralgia and fatigue were also significantly less frequent during the HF period. The average β2-microglobulin level was 27.1 ± 14.7 mg/dl at the start of the study, 22.9 ± 4.9 mg/dl at the beginning of phase II and 22.4 ± 4 mg/dl at the end of phase II (p = 0.01 compared to the start). A significant linear correlation between the normalized protein catabolic rate and eqKt/V was obtained faster during HD than during HF (45 vs. 120 days) indicating that HF affects the nutritional status with mechanisms different from HD. The present study is in agreement with the hypothesis that HF gives an adequate nutritional status with improved clinical stability and well being at a lower Kt/V compared to HD. Both therapies were efficient in controlling the pretreatment β2-microglobulin level.RH release

IN PAZIENTI INCIDENTI IN DIALISI CRONICA IL CHARLSON INDEX È UN PREDITTORE INDIPENDENTE DI BASSI LIVELLI CIRCOLANTI DI PARATORMONE. UNO STUDIO MULTICENTRICO ITALIANO

Introduzione. Vi è una crescente necessità di avviare a trattamento dialitico cronico pazienti anziani, frequentemente affetti da plurime comorbidità. Allo stato delle conoscenze non è noto se tale fenomeno interferisca con la presenza di alterazioni della funzione paratiroidea e del metabolismo minerale. Scopi. Scopo del lavoro è stato quello di studiare la prevalenza delle principali alterazioni della funzione paratiroidea e del metabolismo minerale in pazienti incidenti in dialisi cronica, descrivendo tali alterazioni in rapporto al grado di comorbidità presente. Pazienti e metodi. È stato condotto uno studio osservazionale cross-sectional che ha coinvolto 37 Centri Italiani. In ciascun Centro sono stati raccolti dati di tutti i pazienti adulti che, per esaurimento della funzione renale nativa, sono stati consecutivamente avviati a trattamento dialitico cronico nel corso dell’ultimo anno. Sono stati raccolti dati di 364 pazienti incidenti in dialisi con età media 64 ± 15 anni (65% di sesso maschile, 37% con diagnosi di nefropatia diabetica e/o ipertensiva, 8% avviati a dialisi peritoneale).Il Charlson Index, uno score validato che include numerose patologie croniche,è stato utilizzato per misurare il grado di comorbidità. Risultati. Oltre il 25% dei pazienti incidenti in dialisi era ultrasettantacinquenne ed il 14.3% era ultraottantenne. Il 21.3% dei pazienti presentava difficoltà a muoversi autonomamente e l’indice di comorbidità (Charlson score M±DS) era 4.01 ± 2.89. Ad avvio dialisi solo il 27% dei pazienti aveva iPTH compreso tra 150 e 300 pg/ml, mentre il 73% era al di fuori di tale intervallo target. Alterazioni del metabolismo minerale ed importanti quadri di disfunzione paratiroidea erano tutt’altro che infrequenti: iPTH 500 pg/ml era presente nel 16.5% dei pazienti. In meno della metà dei pazienti la calcemia corretta era nell’intervallo target 8.4 -9.5 mg/dl: il 39% era al di sopra ed il 14% al di sotto di tale range calcemico. Inoltre una fosforemia > 5.5 mg/dl era presente nel 36% dei casi. Nei pazienti che presentavano comorbidità, il Charlson score presentava una significativa correlazione inversa con i livelli di iPTH (Spearman rho -0.17, P=0.002). La significativa relazione inversa tra la variabile dipendente iPTH ed il Charlson score (-0.20, P=0.009) era anche riscontrata in un modello di regressione multipla in cui le altre covariate erano: l’età (P=N/S), il sesso (P=N/S), la fosforemia (0.19, P=0.005), la calcemia corretta (- 0.20, P=0.003) e la somministrazione di sali di calcio (P=N/S) ed analoghi della vitamina D (0.30, P<0.001). Conclusioni. Questo studio evidenzia come la popolazione incidente in dialisi cronica sia caratterizzata da un alto indice di comorbidità e da alterazioni del metabolismo minerale e della funzione paratiroidea, spesso severe già in queste fasi. L’indice di comorbidità si è dimostrato un significativo ed indipendente predittore di bassi livelli di iPTH

Risk for chronic kidney disease in the general population: Italian reports for World Kidney Days 2007-2009

The prevalence of chronic kidney disease (CKD) has rapidlyincreased in recent decades in many countries, leading toconsistent economic implications. Considering the fact thatpatients surviving to CKD often develop end-stage renal disease,the number of patients requiring replacement therapyreached 169/million population (pmp) in Italy in 2004 and342 pmp in the Unites States. Furthermore, CKD weighs onpatients survival with a considerably increased cardiovascular(CV) morbidity and mortality

Effects of different membranes and dialysis technologies on patient treatment tolerance and nutritional parameters

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 advantages (in terms of treatment tolerance, nutritional parameters and pre-treatment beta(2)-microglobulin levels) over a traditional membrane (Cu-prophan(R)). 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(R) 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(R) 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(R) 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