The relationship between lactose tolerance test results and symptoms of lactose intolerance.

Department of Gastroenterology, University Hospital Maastricht, The Netherlands. OBJECTIVE: A standard for the assessment of lactose malabsorption does not exist. As measured by lactose tolerance tests, insufficient increase in blood glucose or increased breath hydrogen (H2) excretion after lactose ingestion is regarded as pathological. In this study, we have tried to elucidate the relationship between lactose tolerance test results and symptoms after a lactose challenge. This relationship might be an indicator for the validity of the test. METHODS: In a prospective study, 309 consecutive patients with suspected lactose malabsorption underwent a lactose tolerance test. After consumption of 50 g of lactose, blood glucose and breath H2 concentrations were measured. During the test (240 min), the severity of bloating, flatulence, abdominal distention, and diarrhea were semiquantitatively scored as 0, 1, or 2. The individual sum of these four scores was calculated and denoted as the total symptom score (TSS). All subjects were classified according to their TSS to compare symptoms with peak breath-H2 concentration and change in blood glucose concentration, respectively. RESULTS: The glucose and breath H2 response were pathological in 51.1 and 39.5% of cases, respectively. A stepwise increase in TSS of 1 point was associated with a significant increase (p < 0.05) in mean peak H2 concentration. However, a significantly lower glucose increment compared with patients with a TSS of 0 was found only in patients with a TSS of 2 or 4. The mean symptom score differed significantly between the positive and negative breath tests (p < 0.001), but did not differ between the positive and negative glucose response results. CONCLUSIONS: This study shows that GI symptoms after a lactose challenge are strongly associated with the amount of H2 excretion. The relationship between the increase in glucose concentration and symptoms after a lactose load is less evident. Thus, the H2 breath test seems to be superior to the measurement of blood glucose increment as a diagnostic tool in lactose malabsorption, although the true predictive value of this test only can be determined after a period of dietary treatment

Reference values for multifrequency bioimpedance analysis in dialysis patients

Reference values for multifrequency bioimpedance analysis in dialysis patients.van de Kerkhof J, Hermans M, Beerenhout C, Konings C, van der Sande FM, Kooman JP.St. Catharina Hospital, Eindhoven, The Netherlands.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 &lt; 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.<br/

“What matters to you?”: The relevance of patient priorities in dialysis care for assessment and clinical practice

Background: Dialysis patients are confronted with numerous, complex problems, which make it difficult to identify individual patient's most prominent problems. The objectives of this study were to (1) identify dialysis patients' most prominent problems from a patient perspective and (2) to calculate disease-specific norms for questionnaires measuring these problems. Methods: One hundred seventy-five patients treated with hemodialysis or peritoneal dialysis completed a priority list on several domains of functioning (e.g., physical health, mental health, social functioning, and daily activities) and a set of matching questionnaires assessing patient functioning on these domains. Patient priorities were assessed by calculating the importance ranking of each domain on the priority list. Subsequently, disease-specific norm scores were calculated for all questionnaires, both for the overall sample and stratified by patient characteristics. Results: Fatigue was listed as patients' most prominent problem. Priorities differed between male and female patients, younger and older patients, and home and center dialysis patients, which was also reflected in their scores on the corresponding domains of functioning. Therefore, next to general norm scores, we calculated corrections to the general norms to take account of patient characteristics (i.e., sex, age, and dialysis type). Conclusions: Results highlight the importance of having attention for the specific priorities and needs of each individual patient. Adequate disease-specific, norm-based assessment is not only necessary for diagnostic procedures but is an essential element of patient-centered care: It will help to better understand and respect individual patient needs and tailor treatment accordingly.Applied Ergonomics and DesignHR HealthExternenregistrati

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

The relationship between reticulocyte hemoglobin content with C-reactive protein and conventional iron parameters in dialysis patients. Hackeng CM, Beerenhout CM, Hermans M, Van der Kuy PH, Van der Dussen H, Van Dieijen-Visser MP, Hamulyak K, Van der Sande FM, Leunissen KM, Kooman JP. Department of Clinical Chemistry, University Hospital Maastricht, The Netherlands. 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 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 ferriti

Spatial inhomogeneity of common carotid artery intima media is increased in dialysis patients and is independently related to antibodies to oxidized-LDL and serum fetuin-A concentration

Background. Structural abnormalities of the common carotid artery (CCA), as assessed by ultrasound techniques, are related to cardiovascular outcome in dialysis patients. An increased intima media thickness (IMT) of the CCA may both represent a reaction to a haemodynamic burden as well as atherosclerosis. With a new ultrasound technique CCA-IMT and IMT-inhomogeneity, a novel parameter of spatial variance of the IMT, were measured and related to traditional and non-traditional risk factors. Methods. In a cross-sectional study, we included 134 dialysis patients, aged 61 +/- 13 years (103 on haemodialysis, 31 on peritoneal dialysis) and 41 controls, aged 60 +/- 8 years. Age, sex, pulse pressure, diabetes, prevalent cardiovascular disease (CVD) and height were included in the basic multiregression analysis. Ultrasound examination of the CCA was performed. We also measured serum fetuin-A, high-sensitivity C-reactive protein (hsCRP), antibodies to oxidized low density lipoproteins (anti-oxLDL antibodies), calcium, phosphate, albumin and parathyroid hormone. Results. Compared with controls, dialysis patients had a greater CCA-IMT (670 mu m vs 590 +/- 10 mu m; P = 0.002) and a greater CCA-IMT inhomogeneity (11.0 vs 8.1%; P = 0.013). Dialysis patients with CVD had a greater CCA-IMT (734 mu m vs 631 mu m; P = 0.001) and IMT-inhomogeneity (13.2 vs 9.7; P = 0.008) compared with patients without CVD. IMT-inhomogeneity strongly correlated with IMT (R = 0.65, P <0.0001). In multiregression analysis, serum fetuin-A and anti-oxLDL antibodies correlated with IMT-inhomogeneity but not with IMT. HsCRP neither correlated with IMT-inhomogeneity nor with IMT. Conclusion. The present study shows that CCA-IMT and IMT-inhomogeneity were increased in dialysis patients compared with controls. Although CCA-IMT and IMT-inhomogeneity are related, the different associations between both measurements and non-traditional risk factors show that they are distinct entities