Serum small-dense LDL abnormalities in chronic renal disease patients.

Cardiovascular disease (CVD) is the principal cause of mortality in chronic kidney disease (CKD) patients. Dyslipoproteinaemia is a common metabolic derangement in CKD and a traditional risk factor for CVD. This study investigates serum lipoprotein, especially small-dense low-density lipoprotein (sd-LDL), abnormalities in CKD patients. A total of 131 CKD patients (age: 59 +/- 12 years, male = 64) diagnosed according to Kidney Disease: Improving Global Outcomes, 2004 (KDIGO) and 121 age- and gender-matched control subjects (age: 58 +/- 6 years, male = 62) were recruited from Hong Kong and Macau. Serum total cholesterol (TC), triglyceride (TG), high-density lipoprotein-cholesterol (HDL-C) and direct LDL-C were assayed enzymatically. In addition, sd-LDL, together with very low density and intermediate-density lipoproteins (VLDL and IDL) were measured by US Food and Drug Administration (FDA)-approved polyacrylamide gradient gel electrophoresis. Compared to controls, CKD patients showed significantly decreased TC, LDL-C, normal-size LDL and HDL-C with increased TG, VLDL, IDL and sd-LDL (all P < 0.01). The increased sd-LDL and decreased normal-size LDL fractions resulted in a significantly elevated sd-LDL:LDL ratio in CKD (P < 0.005). In contrast to the low TC and LDL-C, sd-LDL and sd-LDL:LDL ratio were significantly elevated in CKD. Thus, sd-LDL will be used increasingly for CVD risk assessment in CKD and other diseases that show lipoprotein derangement.

Change in bacterial aetiology of peritoneal dialysis-related peritonitis over 10 years: experience from a centre in South-East Asia.

This study reviewed 1787 episodes of peritoneal dialysis (PD)-related peritonitis in 544 patients between 1994 and 2003. The overall rate of peritonitis was 0.68 episodes/year of PD, but decreased from 1.10 to 0.46 episodes/year between 1994 and 2003. The incidence of peritonitis caused by coagulase-negative staphylococci declined between 1994 and 1998 from 0.21 to 0.06 episodes/year of PD, coinciding with a reduction in the use of spike PD sets. There was a 60.1% response rate to antibiotics throughout the period, but the percentage of cases that required modification of the initial empirical antibiotic regimen rose from 13.6% to 58.7%, indicating that treatment should be individualised.

The importance of residual renal function in dialysis patients.

Preserving residual renal function has always been the primary clinical goal for every nephrologist managing patients with chronic kidney disease. There is no reason why this important goal should not extend to patients with stage 5 chronic kidney disease receiving dialysis. Indeed, there is now clear evidence that preserving residual renal function remains important after the commencement of dialysis. Residual renal function contributes significantly to the overall health and well-being of dialysis patients. It not only provides small solute clearance but also plays an important role in maintaining fluid balance, phosphorus control, and removal of middle molecular uremic toxins, and shows strong inverse relationships with valvular calcification and cardiac hypertrophy in dialysis patients. Decline of residual renal function also contributes significantly to anemia, inflammation, and malnutrition in patients on dialysis. More importantly, the loss of residual renal function, especially in patients on peritoneal dialysis, is a powerful predictor of mortality. In addition, there is increasing evidence that residual renal and peritoneal dialysis clearance cannot be assumed to be equivalent qualitatively, thus indicating the need to preserve residual renal function in patients on dialysis. In this article, we will review evidence that residual renal function is important in dialysis patients (especially peritoneal dialysis) and outline potential strategies that may better preserve residual renal function in dialysis patients.

Troponin T, left ventricular mass, and function are excellent predictors of cardiovascular congestion in peritoneal dialysis.

Patients on maintenance peritoneal dialysis (PD) are frequently complicated with volume overload. In this study, we sought to evaluate troponin T testing alone or in combination with echocardiographic measures in predicting cardiovascular congestion in PD patients. This was a prospective study of 222 chronic PD patients with echocardiography and measurement of serum troponin T carried out at baseline. Patients were followed for 3 years or until death. The end point was first episode of cardiovascular congestion. Troponin T emerged as an independent predictor of cardiovascular congestion (hazard ratio, 2.98, 95% confidence intervals (CI), 1.19-7.42) in a multivariable Cox regression model, including also left ventricular mass index (LVMi) and ejection fraction (EF). Patients with troponin T>median (0.06 microg/l) and EFmedian but EF>50% had a 3.10-fold (95% CI, 1.71-5.63) and 1.88-fold (95% CI, 1.05-3.38) adjusted risk of cardiovascular congestion, respectively, than those with troponin T50%. Patients with troponin T>median and LVMi>or=median (96.23 g/m2.7) had a 2.68-fold (95% CI, 1.39-5.19) adjusted risk of cardiovascular congestion than those with troponin T

Extrapolation of reciprocal creatinine plot is not reliable in predicting the onset of dialysis in patients with progressive renal insufficiency.

BACKGROUND: Reciprocal creatinine plot is often used to monitor patients with progressive renal insufficiency and to predict the onset of dialysis, although the latter practice has not been validated. OBJECTIVE: We examined whether extrapolating the reciprocal creatinine plot can predict the onset of dialysis. SETTING: Single centre study in the dialysis unit of a University teaching hospital. DESIGN: We studied 170 consecutive patients with progressive renal insufficiency referred to a single nephrology unit and subsequently dialysed. Reciprocal creatinine plot was constructed by all available serum creatinine values before dialysis (the 'definitive plot'). Four 'interim plots' were constructed for each patient by using serum creatinine below 400, 500, 600 and 700 micromol L(-1). Interim plots with at least five points and Pearson's r > 0.9 were analysed. The date of dialysis was predicted from the least squares linear regression formula and a target serum creatinine level cor- responding to estimated creatinine clearance of 7 mL min-1, at which dialysis was recommended. RESULTS: The median duration of observation was 25 months. After serum creatinine 500 micromol L(-1), the slope of the interim plot remained stable and extrapolation was possible in 117 patients (68.8%). However, the limits of agreement for predicting the onset of dialysis were wide (from -11.7 to +9.5 months). At this creatinine level, the onset of dialysis fell within 1 month of the predicted onset in only 41 patients (24.1%). The limits of agreement for prediction narrowed when time points of higher serum creatinine were included into the plot. However, nine patients (5.3%) required dialysis within 1 month at creatinine 600 micromol L(-1) and the dialysis was not predicted by the reciprocal creatinine plot. Target serum creatinine did not correlate with acute serum creatinine at which dialysis was started (r = 0.051, P = 0.51). A slower decline in renal function was associated with a higher prediction error (r = 0.212, P = 0.014). CONCLUSIONS: The onset of dialysis cannot be predicted by extrapolation of the reciprocal creatinine plot because of individual variation in the renal function that require dialysis. Dialysis would be almost imminent in some patients by the time serum creatinine reaches a level that allows accurate construction and extrapolation of a plot.