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Marc Hermans

Publications and source records attributed to Marc Hermans.

3 recordsLinked to original sources
PubMed2004

Reference values for multifrequency bioimpedance analysis in dialysis patients.

BACKGROUND: The role of multifrequency bioimpedance(MF-BIA) in the assessment of fluid status in dialysis patients is still not fully elucidated. Especially, the predictive value of reference values for extracellular water (ECW) has not yet been addressed. Aim of the present study was to validate cut-off values for MF-BIA in the diagnosis of hypervolemia in dialysis patients, using strict clinical criteria and echocardiography as reference techniques. METHODS: 90 patients [42 on hemodialysis; 48 on peritoneal dialysis] were divided into the following groups: clinically normovolemic (mean 24- or 48-hour systolic blood pressure below 133 mm Hg without use of antihypertensive agents; n = 12), 'hypervolemic' (mean systolic blood pressure above 133 mm Hg with 2 or more antihypertensive agents; n = 34) or undetermined (n = 44). The 80th percentile for normalized ECW in the clinically normovolemic patients was used as reference value. 20 healthy age-matched controls were included for comparison. RESULTS: The 80th percentiles for ECW:body weight (BW) and ECW:height in 'normovolemic' subjects were, respectively, 0.245 liters/kg and 10.96 liters/m in males, and 0.232 liters/kg and 9.13 liters/m in females. ECW:BW and ECW:height were above these values in, respectively, 26 (sensitivity 76%) and 29 (sensitivity 86%) of the 34 'hypervolemic' patients. In the undetermined group, left ventricular end-diastolic diameter was significantly different between patients with normalized ECW below and above these cut-off values (49.0 +/- 5.1 vs. 52.4 +/- 5.7 mm; p < 0.05). Use of the ECW:TBW ratio resulted yielded low sensitivity (45%). ECW:height was lower in the 'normovolemic' dialysis patients compared to healthy controls (9.7 +/- 1.3 l/m versus 12.2 +/- 1.9 l/m). CONCLUSION: In our study population, ECW by MF-BIA, normalized for height was able to predict hypervolemia, based on strict clinical criteria, with a sensitivity of 86% and a specificity of 80%. The normalization procedure for ECW may influence the classification of hydration status. Strictly normotensive dialysis patients had lower normalized ECW than healthy control subjects.

Adult↗
PubMedDate not supplied

The relationship between reticulocyte hemoglobin content with C-reactive protein and conventional iron parameters in dialysis patients.

Adequate iron stores are a prerequisite for successful erythropoietin (EPO) therapy in hemodialysis (HD) patients. Nevertheless, iron status estimation in HD patients remains problematic, as most parameters are influenced by inflammation. The reticulocyte hemoglobin content (CHr) has recently been proposed as a useful tool in iron status assessment. However, the effect of inflammation on CHr remains unstudied. This study aimed to assess the relationship between CHr with other parameters of iron status as well as with C-reactive protein (CRP). This relationship was studied in all the patients (n=61) at our dialysis unit. CHr was significantly and positively related to transferrin saturation (TS) (rho=0.26; p<0.05) and inversely to the percentage of hypochromic red blood cells (%Hypo) (rho=-0.63; p<0.0001), but not to serum ferritin. CHr was strongly and inversely related to log CRP (rho=-0.50; p<0.0001). Despite the use of maintenance intravenous (i.v.) iron doses and relatively high serum ferritin levels, a large percentage of patients were in a state of functional iron deficiency (%Hypo > or = 6 in 41% of patients and CHr < or = 29 pg in 13% of patients). This percentage was far lower in patients with CRP levels below the detection limit (2 mg/L) (26% and 0%, respectively). In conclusion, CHr is related to both TS and %Hypo, but not to serum ferritin, and is strongly influenced by the presence of inflammation (as determined by CRP). In patients with elevated CRP levels, it is very difficult to reach target iron status levels without exceeding the upper limits for serum ferritin.

Aged↗