The self-locating catheter: clinical experience and follow-up.

Background: The self-locating catheter invented by Nicola Di Paolo has been used increasingly in Italy and elsewhere since 1994, with about a thousand patients currently implanted every year. Twelve grams of tungsten inserted into the tip of the conventional Tenckhoff catheter during extrusion does not significantly change its form, but suffices to keep the tip firmly in the Douglas cavity.

Objective: The aim of the present study was to confirm our preliminary results in a large population of peritoneal dialysis patients.

Crystallization inhibitors in the pathophysiology and treatment of nephrolithiasis.

It is currently agreed that stone formation in the urinary tract requires supersaturation with respect to a given solid phase. However, this principle fully applies only to stones other than calcium-containing stones, in which case compounds acting as inhibitors are postulated to naturally occur in urine. Stone formation would therefore ensue from an imbalance between promoters and inhibitors.

Cost analysis of blood purification in intensive care units: continuous versus intermittent hemodiafiltration.

Background: We implemented a program for continuous renal replacement therapies (CRRT) in intensive care units (ICU) based on the cooperative work of dialysis and ICU personnel. Our aim was to report the main details of this program and compare its cost with that of intermittent hemodiafiltration (IHDF).

Methods: The study referred to 181 ICU patients with renal failure.

[Intact whole bioactive parathormone: problems arising from comparing different methods].

Background: Parathyroid hormone (PTH) has important applications in the nephrological clinical practice. Because assays of Intact PTH (I-PTH) are liable to interferences by N-truncated fragments, a novel method for whole-(1-84) PTH has been proposed. This study is aimed at comparing the latter with some of the previous I-PTH assays.

Renal stones: from metabolic to physicochemical abnormalities. How useful are inhibitors?

Despite intensive studies in the last decades many aspects of nephrolithiasis still remain to be elucidated. Supersaturation with respect to lithogenic substances explains stones composed of cystine, uric acid, struvite, and calcium stones secondary to systemic diseases. In this subset there is a clear separation between patients and controls, and stone activity is well related to alterations in the physicochemistry of the urine environment.

Epidemiology of nephrolithiasis.

The overall probability of forming stones differs in various parts of the world: 1-5% in Asia, 5-9% in Europe, 13% in North America, 20% in Saudi Arabia. The composition of stones and their location in the urinary tract, bladder or kidneys may also significantly differ in different countries. Moreover, in the same region, the clinical and metabolic patterns of stone disease can change over time.

[Clinical and metabolic features of renal calculi in adults in regard to age of onset].

Background: In this paper, the clinical and metabolic patterns of nephrolithiasis in different ages of adulthood are studied.

Methods: Eight-hundred patients observed at the Mauriziano Hospital between 1990 and 1995, were classified into 3 groups, on the basis of age at the onset of disease: A: 20 through 39 years; B: 40 through 59; C: 60 years and over.

Results: Calcium-oxalate stones had a lower recurrence in C (19.

Idiopathic calcium nephrolithiasis.

Calcium nephrolithiasis (CaNL) accounts for more than 70% of all renal stones, and its prevalence has increased in the last decades. Under this definition are included patients passing stones, composed of calcium oxalates and/or calcium phosphates. Current views of the pathogenesis of CaNL are based on the role of metabolic abnormalities which concur to render urines more conducive to crystallization.

[Maintenance of the tunnel and skin exit site of peritoneal catheters. Current situation and orientation of the dialysis centers of the Piedmont and the Valle d'Aosta].

A questionnaire was sent to the 23 Dialysis Centers of the Piedmont and Aosta Valley Regions to probe present trend on the choice of peritoneal catheter, its setting, the tunnel conformation, the first use and its maintenance. The nephrologists attach great importance to a well fixed subcutaneous tract of the catheter: this goal is obtained with wide use of pre-molded catheters, often with long and curvilinear tunnel. Avoiding an early use of the catheter and the choice of small volumes in the first weeks will permit an efficient stability of the cuff and the reduction of the risk of leakage.

[Urinary tract infection prevention in catheterized patients. Prevalence National Study: preliminary studies at the Pinerolo Hospital].

Urinary tract infection incidence can be a possible indicator of the quality of health care in hospital. It is now clear that some kind of health care, practice and particular organizational and structural orders change the risk of UTI during hospitalizations. One third of hospital infections can be prevented by carrying out specified rules and guidelines.

[Diabetes mellitus is currently one of the most frequent causes or associated causes of uremia. Data from the Piedmont registry of dialysis and transplantation (update, December 1993)].

A regular dialytic treatment of diabetic patients is until accepted from about twenty years in many areas. Aim of this work was a retrospective analysis of main clinical and survival data of diabetic patients (diabetic nephropathy or diabetes as comorbidous factor = 659 cases) admitted for dialysis in Piedmont (Northern Italy Region about 4,400,000 inhabitants) in the period 1981-1993 (functional recovery and follow-up < 1 month excluded). A progressive increment in incidence of diabetic patients was seen mostly in the aged.

Dialysis-related amyloidosis in a large CAPD population.

We studied 212 patients from 13 Italian dialysis centers to evaluate the clinical aspects of dialysis-related amyloidosis in continuous ambulatory peritoneal dialysis (CAPD). The mean age was 64.2 +/- 12.

[Utilization of EPO in CAPD].

From January 1988 to September 1990 14 uremic patients in CAPD underwent EPO therapy in the Nephrology and Dialysis Unit of the "E. Agnelli" Hospital in Pinerolo. Intravenous routes were used in 5 patients and subcutaneous routes in the remaining 9 patients, with a unified dose of 4000 IU/three times a week.

Bone marrow erythroid precursor Ca++ regulates the response to human recombinant erythropoietin (rHuEPO) in hemodialysis patients.

The modulation of erythropoiesis by erythropoietin is conditioned by the concentration of Ca++ in the cytoplasm of the bone marrow erythroid precursors. We evaluated in vitro erythroid colony development from bone marrow erythroid precursors incubated with increasing concentrations of Ca++ or Ca++ plus 1,25 (OH)2 D3, and bone marrow erythroid precursor cytoplasmic Ca++ concentrations in 10 anemic hemodialysis (HD) patients before and during rHuEPO therapy. Results showed that: a) in vitro: in uremics patients before rHuEPO therapy, bone marrow erythroid precursor cytoplasmic Ca++ was lower than in normal subjects; the addition of Ca++ to the bone marrow erythroid precursors induced a dose-dependent Ca++ and erythroid colony development increase; 1,25 (OH)2 D3 potentiated this effect; b) in vivo: rHuEPO normalized bone marrow erythroid precursor Ca++ and erythroid colony development.

Ca++ and 1,25(OH)2D3 regulate in vitro and in vivo the response to human recombinant erythropoietin in CAPD patients.

In vitro studies indicate that the culture medium Ca++ concentration conditions the response to erythropoietin of bone marrow erythropoietic cells which also have specific receptors for 1,25(OH)2D3. We therefore evaluated in 12 anemic CAPD patients: 1) in vitro with increasing concentrations of Ca++ alone or Ca++ plus 1,25(OH)2D3 a) Ca++ in the bone marrow erythroid cell cytoplasm; b) colony (BFU-E and CFU-E) growth from bone marrow erythroid cells. 2) in vivo before and after 24 weeks of i.

Treatment of anaemia in CAPD patients with recombinant human erythropoietin.

EPO is an effective therapy of anaemia in CAPD patients. Monitoring serum iron level during EPO therapy is essential. Hypertension is frequently seen in patients with EPO therapy.

A human leukemic T cell line (PF-382) inhibits the growth of myeloid and erythroid progenitor cells.

We have recently described a human T cell line, named PF-382, obtained from the pleural effusion of a child with T-acute lymphoblastic leukemia (T-ALL), which expresses phenotypic and functional features of suppression. In this study we report that PF-382 spontaneously releases a factor which inhibits the in vitro growth of myeloid (CFU-GM) and erythroid (BFU-E) progenitor cells. The same effect is obtained when irradiated PF-382 cells are co-cultured with the hemopoietic precursors.