Impact of a low-glucose peritoneal dialysis regimen on fibrosis and inflammation biomarkers.

BACKGROUND: The impact of a low-glucose peritoneal dialysis (PD) regimen on biomarkers of peritoneal inflammation, fibrosis and membrane integrity remains to be investigated. METHODS: In a randomized, prospective study, 80 incident PD patients received either a low-glucose regimen comprising Physioneal (P), Extraneal (E) and Nutrineal (N) (Baxter Healthcare Corporation, Deerfield, IL, USA) (PEN group), or Dianeal (control group) for 12 months, after which both groups continued with Dianeal dialysis for 6 months. Serum and dialysate levels of vascular endothelial growth factor (VEGF), decorin, hepatocyte growth factor (HGF), interleukin-6 (IL-6), macrophage migration inhibitory factor (MIF), hyaluronan (HA), adiponectin, soluble-intracellular adhesion molecule (s-ICAM), vascular cell adhesion molecule-1 (VCAM-1) and P-selectin, and dialysate cancer antigen 125 (CA125), were measured after 12 and 18 months. This paper focuses on results after 12 months, when patients in the PEN group changed to glucose-based PD fluid (PDF). RESULTS: At the end of 12 months, effluent dialysate levels of CA125, decorin, HGF, IL-6, adiponectin and adhesion molecules were significantly higher in the PEN group compared to controls, but all decreased after patients switched to glucose-based PDF. Macrophage migration inhibitory factor level was lower in the PEN group but increased after changing to glucose-based PDF and was similar to controls at 18 months. Serum adiponectin level was higher in the PEN group at 12 months, but was similar in the 2 groups at 18 months. Body weight, residual renal function, ultrafiltration volume and total Kt/V did not differ between both groups. Dialysate-to-plasma creatinine ratio at 4 h was higher in the PEN group at 12 months and remained so after switching to glucose-based PDF. CONCLUSION: Changes in the biomarkers suggest that the PEN PD regimen may be associated with better preservation of peritoneal membrane integrity and reduced systemic vascular endothelial injury.

Dosing regimen and tolerability of methoxy polyethylene glycol-epoetin beta in Chinese dialysis patients.

AIM: To investigate methoxy polyethylene glycol-epoetin beta dosing regimen in treatment naïve subjects and dose conversion in darbepoetin alpha treated subjects, in Chinese dialysis patients. METHODS: Adult Chinese patients on peritoneal dialysis (PD) or haemodialysis (HD), with no prior treatment with erythropoiesis-stimulating agents and haemoglobin below 8 g/dL (Group I) or receiving darbepoetin alpha and had stable haemoglobin at 10-12 g/dL (Group II) were included in this prospective open-label study. In Group I methoxy polyethylene glycol-epoetin beta was started at 0.6 µg/kg subcutaneously fortnightly till haemoglobin reached 10 g/dL, after which it was given monthly. A dose conversion table was devised for Group II. Follow-up was 36 weeks. RESULTS: Forty-five patients were included. Haemoglobin in Group I (n=23, PD/HD:19/4) increased from 7.5 ± 0.9 g/dL at baseline to 10.7 ± 1.0 g/dL after 16 weeks, while it remained stable at 10.4 ± 1.0 g/dL after conversion in Group II (n=22, PD/HD:15/7). Actual dose required after stabilization was 1.7 µg/kg per month in Group I and 2.3 µg/kg per month in Group II. Median number of dose adjustment was three in Group I and one in Group II, while haemoglobin overshoot to 13 g/dL or above occurred in 4.4% and 9.1%, respectively. No significant side-effect was observed. CONCLUSIONS: Our dosing regimen for methoxy polyethylene glycol-epoetin beta, for treatment naïve subjects or for conversion from darbepoetin alpha, is safe and effective. The dose required to achieve a haemoglobin concentration of 10-11 g/dL in Chinese dialysis patients is approximately 2 µg/kg monthly.

Impact of nephrotic edema of the lower limbs on obstructive sleep apnea: gathering a unifying concept for the pathogenetic role of nocturnal rostral fluid shift.

BACKGROUND: Nocturnal rostral fluid shift has been suggested to be a risk factor for obstructive sleep apnea (OSA) in healthy subjects after lower body positive pressurization. It remains unclear whether this may apply to subjects with nephrotic lower limb edema and, if so, whether disease remission may reverse the accompanying OSA. METHODS: Patients who presented with steroid-responsive primary nephrotic syndrome with lower limb edema as the predominant presenting clinical feature were recruited. They underwent one overnight polysomnography (PSG) before treatment and a repeat testing after achieving remission of the nephrotic edema. RESULTS: Among 23 consecutive nephrotic subjects, 11 (48%) had polysomnographic evidence of sleep apnea [apnea-hypopnea index (AHI)≥5] upon presentation. After steroid-based treatment, there was remission of proteinuria associated with complete disappearance of lower limb edema, significant reduction of body mass index, waist, hip and calf circumferences and total body water mainly in the extracellular compartment. Repeat PSG, performed 8.1±2.6 months later, showed that the overall (N=23) respiratory disturbance index (RDI) and AHI fell from 17.3±5.0 to 8.7±2.5 (P<0.05) and from 16.3±5.1 to 7.8±2.3 (P=0.057), respectively. Among the 11 subjects with sleep apnea detected at baseline, their AHI and RDI fell from 33.4±7.8 to 15.0±3.7 (P<0.05) and from 34.8±7.6 to 16.5±4.0 (P<0.05), respectively. There was also concomitant improvement in sleep efficiency, mean nocturnal oxygen saturation, shorter duration during sleep with oxygen saturation<95 and <90% and reduced desaturation index. There was also subjective improvement in self-reported daytime sleepiness. CONCLUSIONS: Nephrotic lower limb edema is associated with disturbed respiratory breathing and increased propensity to OSA, which was reversed upon remission of the nephrosis. This gathers a unifying concept for the role of nocturnal rostral fluid shift in the pathogenesis of OSA.