Efficiency and nutritional parameters in an elderly high risk population on hemodialysis and hemodiafiltration in Italy and France: different treatments with similar names?

BACKGROUND: Choice of dialysis is context sensitive, explored for PD and extracorporeal dialysis, but less studied for haemodialysis (HD) and hemodiafiltration (HDF), both widely employed in Italy and France; reasons of choice and differences in prescriptions may impact on dialysis-related variables, particularly relevant in elderly, high-comorbidity patients. METHODS: The study involved two high-comorbidity in-hospital cohorts, treated in Centers with similar characteristics, in Italy (Cagliari) and France (Le Mans). All patients (204) agreed to participate. Stable cases on thrice-weekly dialysis, with at least 2 months follow-up were selected (180 patients, Males 59.4%, median age 71 years, vintage 4.3 years, Charlson index 9). Univariate and multivariate correlations between baseline data, HD-HDF, dialysis efficiency and nutritional markers were assessed. RESULTS: In Le Mans HDF was mainly chosen to increase efficiency (large surface dialysers, high convective volume; 76.3% of the patients), in Cagliari to improve tolerance (smaller surfaces, lower convective volume; 59% of patients). Kt/V was similar in HD and HDF, and in both settings(median Kt/V Daugirdas 2: 1.6); in the setting of high efficiency no correlation was found between Kt/V, BMI, urea, creatinine, n-PCR and phosphate. The relationship between Kt/V and albumin was divergent: a weak consensual increase was present in Cagliari, a decrease in Le Mans, suggesting a role of albumin losses with high convective volumes. In the multivariate analysis, after adjustment for other covariates (including comorbidity and type of treatment) low albumin level < 3.5 g/dl was highly correlated with setting of study: Le Mans (OR: 7.155 (2.955-17.324)). The multivariate analysis confirmed a role of type of treatment, with higher risk of low albumin levels in HDF (OR: 3.592 (1.466-8.801)), and of comorbidity (Charlson index> = 7 (OR: 3.153 (1.311-7.582)), MIS index> = 7 (OR: 5.916 (2.457-14.241)). CONCLUSIONS: The different prescriptions of HD and HDF may have similar effects on dialysis efficiency, but diverging effects on crucial nutritional markers, such as albumin levels, probably more evident in high-comorbidity populations.

Metformin associated lactic acidosis: a case series of 28 patients treated with sustained low-efficiency dialysis (SLED) and long-term follow-up.

BACKGROUND: Metformin associated lactic acidosis (MALA) is a well-known serious side effect of biguanides. However, the best treatment strategy remains a matter of debate. In the last 14 years, we observed a significant increase in hospitalizations for MALA to our Center. We report the outcomes of our clinical and therapeutic approach. METHODS: This is a single-center case series. Twenty-eight patients affected with MALA and acute kidney failure admitted between January 2000 and September 2014 were included. We analyzed comorbidities, laboratory tests and clinical parameters at admission, at 36 h and at discharge. All patients were treated with sustained low-efficiency dialysis (SLED) until normalization of serum lactate (≤ 3 mmol/L), bicarbonate (between 20 and 25 mmol/L) and potassium (between 4.0 and 5.1 mmol/L). RESULTS: The mortality rate was 21.4%, with all of the events occurring within 24 h from admission, and before or during the first hemodialysis treatment. Precipitating causes included; acute dehydration (86.4%), systemic inflammatory response syndrome (SIRS) (57.1%), sepsis (10.7%), nephrolithiasis (14.6%) and exposure to iodinated contrast (7.1%). No further episodes of lactic acidosis were described after discontinuing the drug over a mean follow-up of 27.2 months. Furthermore, while in 2010, we had a peak incidence of MALA of 76.8 cases per 100,000 patients on metformin, this rate fell after an education campaign conducted by specialists on the proper usage of metformin in patients at risk of MALA. Although the fall in incidence after the educational program was not necessarily causal, in 2014 the incidence was 32.9/100,000. CONCLUSIONS: We report an improved mortality rate in patients affected with MALA and acute kidney injury treated with SLED compared with other series published in literature. Rapid introduction of effective hemodialysis is critical in improving outcomes.

Immunosuppressive treatment in dialysis patients.

Immunosuppressive treatment is a critical procedure in dialysis patients, in whom an increased risk of infection is already present. Haemodialytic treatment increases the patient's susceptibility to bacterial infection, mainly by impairing polymorphonuclear leukocyte phagocytosis, but it can also restore the patient's immunological defences by improving the T-cell function, which is reduced by pre-dialysis uraemia. Patients on dialysis usually continue the immunosuppressive treatment that had been established for the illness that caused their renal failure [e.g. systemic lupus erythematosus (SLE) or renal vasculitis]. Less frequently, patients on dialysis need immunosuppression for immunological or inflammatory diseases that appear 'de novo' after initiation of dialysis. SLE and antineutrophil cytoplasmic antibody (ANCA)-related vasculitides are immunological illnesses that frequently cause end-stage renal failure (ESRF). A reduction in serological and/or clinical activity is usually observed in SLE patients after they reach ESRF, but a similar or increased frequency of extrarenal relapse episodes in lupus patients after the beginning of the dialysis, compared with the pre-dialysis period, has also been described. Frequency of relapse episodes in patients on dialysis treatment for ANCA-related vasculitides varies from 10 to 30% per patient/year in different reports, and it is higher than the frequency of relapses after renal transplantation; anti-rejection therapy seems to be the most likely protective factor in these conditions. The treatment of relapse episodes in SLE or ANCA vasculitis in dialysis-dependent patients is usually not different from treatment of relapses in patients with dialysis-independent renal function. However, the risk of severe infection caused by immunosuppressive treatment is relevantly higher in dialysis patients. Furthermore, there is a lack of prospective controlled studies indicating the optimal management of immunosuppressive protocols in dialysis patients. A particularly careful assessment of the patient's risks and benefits is necessary in deciding how long immunosuppressive treatment should last after acute or rapidly progressive renal damage, that should require dialysis treatment, in patients with SLE or ANCA vasculitis. In the above conditions, the risks of prolonging immunosuppressive treatment must be balanced against the relatively good prognosis offered to these patients by dialysis and renal transplantation. In a retrospective review of 24 patients receiving long-term steroid therapy (>3 months) in our dialysis unit in the past 5 years, we found relevant clinical differences in the patients receiving steroid treatment compared with 24 controls. Steroid-treated patients showed less favourable nutritional conditions, with lower serum albumin and body mass index vs non-steroid-treated patients; moreover, C-reactive protein values were persistently higher in the steroid-treated group. Steroid treatment in these patients was usually performed at the beginning of regular dialysis, as a continuation of the treatment that started before the initiation of dialysis. Only two patients, who needed a prolonged low-dose steroidal treatment to control a malnutrition-inflammation-atherosclerosis (MIA) syndrome, started steroids many years after beginning dialysis. Steroid treatment was effective in improving the nutritional condition and inflammatory symptoms in these two patients after all conventional measures had failed.