The low-protein diet for chronic kidney disease: 8 years of clinical experience in a nephrology ward.

BACKGROUND: Guidelines indicate that a low-protein diet (LPD) delays dialysis in severe chronic kidney disease (CKD). We assessed the value of these guidelines by performing a retrospective analysis in our renal clinical practice. METHODS: The analysis was performed from 1 January 2010 to 31 March 2018 in 299 CKD Stage 4 patients followed for 70 months in collaboration with a skilled nutritionist. The patients included 43 patients on a controlled protein diet (CPD) of 0.8 g/kg/day [estimated glomerular filtration rate (eGFR) 20-30 mL/min/1.73 m2 body surface (b.s.)], 171 patients on an LPD of 0.6 g/kg/day and 85 patients on an unrestricted protein diet (UPD) who were not followed by our nutritionist (LPD and UPD, eGFR <20 mL/min/1.73 m2 b.s.). RESULTS: eGFR was higher in CPD patients than in UPD and LPD patients (21.9 ± 7.4 mL/min/1.73 m2 versus 17.6 ± 8.00 mL/min/1.73 m2 and 17.1 ± 7.5 mL/min/1.73 m2; P = 0.008). The real daily protein intake was higher in UPD patients than in LPD and CDP patients (0.80 ± 0.1 g/kg/day versus 0.6 ± 0.2 and 0.63 ± 0.2 g/kg/day; P = 0.01). Body mass index (BMI) was stable in the LPD and CPD groups but decreased from 28.5 ± 4.52 to 25.4 ± 3.94 kg/m2 in the UPD group (P < 0.001). The renal survival of UPD, LPD and CPD patients was 47.1, 84.3 and 90.7%, respectively, at 30 months (P < 0.001), 42.4, 72.0 and 79.1%, respectively, at 50 months (P < 0.001) and 42.4, 64.1 and 74.4%, respectively, at 70 months (P < 0.001). The LPD patients started dialysis nearly 24 months later than the UPD patients. Diet was an independent predictor of dialysis [-67% of RR reduction (hazard ratio = 0.33; confidence interval 0.22-0.48)] together with a reduction in BMI. CONCLUSIONS: An LPD recommended by nephrologists in conjunction with skilled dietitians delays dialysis and preserves nutritional status in severe CKD.

Corticosteroid Treatment Influences TA-Proteinuria and Renal Survival in IgA Nephropathy.

The clinical course of IgA nephropathy (IgAN) and its outcome are extremely variable. Proteinuria at baseline has been considered one of the most important risk factors. More recently, mean proteinuria of follow-up (time-average proteinuria: TAp) was described as a stronger marker of renal survival, suggesting to consider it as a marker of disease activity and response to treatment. We evaluated predictors of renal survival in IgAN patients with different degrees of renal dysfunction and histological lesions, focusing on the role of the therapy in influencing TAp. We performed a retrospective analysis of three prospective, randomized, clinical trials enrolling 325 IgAN patients from 1989 to 2005. Patients were divided into 5 categories according to TAp. The primary endpoint of the 100% increase of serum creatinine occurred in 54 patients (16.6%) and renal survival was much better in groups having lower TAp. The median follow up was 66.6 months (range 12 to 144). The primary endpoint of the 100% increase of serum creatinine occurred in 54 patients (16,6%) and renal survival was much better in groups having lower TA proteinuria. At univariate analysis plasma creatinine and 24h proteinuria, systolic (SBP) and diastolic (DBP) blood pressure during follow-up and treatment with either steroid (CS) or steroid plus azathioprine (CS+A) were the main factors associated with lower TAp and renal survival. At multivariate analysis, female gender, treatment with S or S+A, lower baseline proteinuria and SBP during follow-up remained as the only variables independently influencing TAp. In conclusion, TA-proteinuria is confirmed as one of the best outcome indicators, also in patients with a severe renal insufficiency. A 6-month course of corticosteroids seems the most effective therapy to reduce TAp.

[The ambiguous concept of predialysis: proposal for a model]. / L'ambiguita' del concetto di predialisi: proposta di un modello.

In 2009, 90% of nephrology centers in Lombardy declared to have a ''predialysis'' outpatient department, without, however, specifying its meaning. Research carried out in 2008 among nephrology centers in Piemonte showed how ambiguous this term was. According to the 2007 EDTA-ERA Registry, about 68% of European nephrology centers stated that they had an outpatient department for stage 4-5 CKD patients, but no information was available about the role of patients in the choice of dialysis. It is known that when the predialysis phase is poorly managed, the patient's rehabilitation will be more difficult. Dissatisfaction with dialysis often leads to withdrawal from dialysis, as several registries have shown. For this reason, we created a predialysis course at our center, involving a nephrologist, a nurse, and a dietician. The nephrologist helps the patient choose the most suitable therapeutic strategy, which means that doctor and patient share the responsibility for the treatment choice. The offered options are hemodialysis, peritoneal dialysis, preemptive kidney transplant, and a conservative dietary-pharmacological program. The nurse plans at least 4 meetings: 1) to talk with the patient in order to get to know him or her and his/her family; 2) to provide information about the dialysis procedure and establish the patient's preferences; 3) to clear any doubts about the treatment and deliver a booklet with information about the chosen dialysis procedure; 4) to explain the chosen dialysis procedure; 5) to meet the patient after their preparation for dialysis (vascular access or peritoneal catheter). The dietician manages the dietary programs both for patients who are close to starting dialysis and those on a longlasting conservative program. The predialysis course includes a meeting among all those involved with the patient (nephrologists, nurses, dieticians) to exchange information with the purpose of shared evaluation and decision-making.

Improvement of endothelial function in uraemic patients on peritoneal dialysis: a possible role for 5-MTHF administration.

BACKGROUND: Hyperhomocysteinaemia is an independent risk factor for the development of atherosclerosis. Furthermore, homocysteine induces endothelial dysfunction by an increased inactivation of nitric oxide. In patients with chronic renal failure, the administration of folic acid or its metabolites reduces but does not normalize plasma homocysteine concentrations. METHODS: We examined the effect of oral treatment with 15 mg/daily of 5-methyltetrahydrofolate (5-MTHF) for 12 weeks, on homocysteinaemia and endothelial function in 19 patients undergoing peritoneal dialysis and compared them, for the same period of time, to a control group of patients on peritoneal dialysis. Endothelial function was evaluated by B-mode ultrasonography on the brachial artery. Flow-mediated dilation (FMD) was recorded during reactive hyperaemia produced by the inflation of a pneumatic tourniquet. Nitroglycerine-mediated dilation (NMD) was recorded after sublingual administration of glyceryl trinitrate. Finally, oxidative stress was assessed by evaluating the conjugated dienes plasma levels. RESULTS: Plasma homocysteine concentrations fell by 30% after oral treatment with 5-MTHF. Endothelial function improved significantly after oral 5-MTHF treatment (13.8 +/- 1.2% vs 11.4 +/- 1.4%; P < 0.02) while in the control group we observed a worsening of basal values from 12.1 +/- 2.66% to 8.7 +/- 2.90% (P < 0.02). The conjugated dienes plasma levels did not change either. CONCLUSIONS: Our study demonstrated that 5-MTHF administration improves endothelial dysfunction in patients undergoing peritoneal dialysis. This effect appears to be independent of the reduction in homocysteine plasma levels.