Precision of Biomarkers to Define Chronic Inflammation in CKD

Abstract

Background/Aims: Several inflammatory biomarkers have been found to be associated with cardiovascular disease or all-cause mortality in dialysis patients, but their usefulness in clinical practice or as surrogate endpoints is not certain. The purpose of the present study was to determine the intrapatient variation of C-reactive protein, IL-6, fetuin-A and albumin in a population of dialysis patients. Methods: Apparently healthy dialysis patients with either a tunneled dialysis catheter or fistula had monthly assessments of these biomarkers for a total of four determinations, and the intraclass correlation coefficients were calculated as measures of intersubject variance. Results: Our results showed large within-subject variation relative to the total variation in the measurements (31–46%). Having a tunneled catheter as opposed to a fistula was not significantly associated with mean levels, suggesting that chronic subclinical catheter infection does not explain the variation seen in the biomarkers. In contrast, there was a rapid change in these biomarkers with a clinically apparent acute infection. Conclusion: These results suggest that these biomarkers have limitations for use as surrogate endpoints in clinical trials due to wide fluctuations, even in apparently clinically healthy individuals.

Fetuin-A as a risk factor for mortality in hemodialysis patients

“…Elevated CRP is a well known predictor of mortality and CV deaths in dialysis patients [2,17]. Our study has not confi rmed a negative correlation between serum fetuin-A level and CRP level, which does not accord with published data [2,11], although the study by La Clair et al also found no correlation [3]. Some previous studies have already shown a connection between low serum fetuin-A values and mortality.…”

“…However, the mortality rate in patients with end-stage renal disease (ESRD) is at least 10-20 times higher than in age-and sex-matched controls, and nearly half the deaths result from cardiovascular (CV) causes [2]. Dialysis patients have a large burden of CV disease, with both traditional Framingham and many "non-traditional" risk factors identifi ed [3]. Cross-sectional and follow-up studies on ESRD patients showed that arterial calcifi cations are associated with CV morbidity and are an independent predictor of all-cause and CV mortality [4][5][6][7].…”

“…Th e underlying etiology of the accentuated infl ammatory response in uremia remains poorly understood [9]. Several possible etiologies have been implicated including, but not limited to, tunnelled dialysis catheters, oxidative stress, non-pure water and periodontal disease [3]. Levels of interleukin-6 and C-reactive protein (CRP) are already elevated in earlier stages of chronic kidney disease.…”

Escherichia coli Pyometra Induces Transient Glomerular and Tubular Dysfunction in Dogs

“…Inclusion of a higher number of dogs might have prevented one of the limitations of this study, namely the high variance in the pyometra group. However, it should be highlighted that the existence of an individual kidney function response remains a challenge in infection‐related research studies 44,45 …”

Ten-Year Experience with Sevelamer and Calcium Salts as Phosphate Binders

“…Future trials will clarify whether these effects will result in a favorable outcome with sevelamer phosphate-binding therapy. An important consideration to be made when evaluating biomarkers in CKD is that, in these patients, there are large (nearly 50%) within-subject variations relative to the total variation in measurements (36).…”