[Critical results reporting: the importance of local partnership agreements]. / Overdracht van sterk afwijkende laboratoriumuitslagen.

Critical results should be reported to the physician as soon as possible so that the physician can take the necessary follow-up actions. Failure or non-timely reporting of such results may lead to serious health damage or death to the patient. This article focusses on the reporting of results from the laboratory to the physician and discusses the bottlenecks and the separate (legal) responsibilities of the physician and the laboratory. Improving the process of the reporting and follow-up of critical results is a joint responsibility of the laboratory and the physician requesting the laboratory tests. This could be achieved by local partnership agreements.

Overweight children with type 1 diabetes have a more favourable lipid profile than overweight non-diabetic children.

In the present article, we aimed to compare the cardiometabolic risk between overweight children with and without type 1 diabetes (T1DM). Therefore, data with regard to cardiometabolic risk parameters of 44 overweight Caucasian children (3-18 years) with T1DM were matched with 44 overweight peers without T1DM for sex, ethnicity, age and standard deviation score of BMI (Z-BMI). Detailed history was taken, information regarding anthropometrics and family history were collected and blood pressure was measured. Blood samples were collected for evaluation of lipid profiles (fasting in controls, non-fasting in T1DM children), alanine aminotransferase and HbA1c (in children with T1DM). It was found that overweight children with T1DM had lower median standard deviation score of waist circumference (Z-WC) as compared to the overweight control group [median, 2.0 (interquartile range, IQR, 1.5-2.3) vs. 2.6 (IQR, 2.0-2.9), P < 0.001]. After adjustment for Z-WC, in children with T1DM, median high-density lipoprotein cholesterol levels were significantly higher and median low-density lipoprotein cholesterol lower in T1DM children, as compared to their peers without T1DM [1.40 (IQR, 1.2-1.5) vs. 1.2 (IQR, 1.0-1.3) and 2.7 (IQR, 2.5-3.2) vs. 3.0 (IQR, 2.5-3.4), respectively, all P < 0.01]. When dividing children according to glycaemic status, children with suboptimal glycaemic control had higher values of triglycerides as compared to well-controlled children [1.3 (IQR, 1.0-1.8) vs. 0.96 (IQR, 0.80-1.2), P = 0.036]. In conclusion, overweight children with T1DM have a more favourable lipid profile, as compared to non-diabetic overweight controls, in spite of a higher frequency of a positive family history of CVD, T2DM and hypertension. Still, paediatricians should give extra attention to cardiometabolic risk factors within this vulnerable group, taking into account the already high cardiometabolic risk.

Overweight is highly prevalent in children with type 1 diabetes and associates with cardiometabolic risk.

OBJECTIVES: To determine the prevalence of traditional cardiometabolic risk factors and to assess the effect of overweight/obesity on the occurrence of these risk factors in a cohort of children with type 1 diabetes mellitus (T1DM). STUDY DESIGN: Two hundred eighty-three consecutive patients (3 to 18 years of age) attending an outpatient clinic for T1DM care were included. The prevalence of cardiometabolic risk factors, the metabolic syndrome, and high alanine aminotransferase, were assessed before and after stratification for weight status. RESULTS: Of all children (median age, 12.8 years; interquartile range, 9.9 to 16.0; median diabetes duration, 5.3 years; interquartile range, 2.9 to 8.6), 38.5% were overweight/obese (Z-body mass index > or =1.1). Overall, median HbA1c levels were 8.2% (interquartile range, 7.4 to 9.8), and HbA1c > or =7.5% was present in 73.9%. Microalbuminuria was found in 17.7%, high triglycerides (>1.7 mmol/L) in 17.3%, high LDL-cholesterol (>2.6 mmol/L) in 28.6%, low HDL-cholesterol (<1.1 mmol/L) in 21.2%, and hypertension in 13.1% of patients. In the overweight/obese children with T1DM, versus normal-weight children, a higher prevalence of hypertension (23.9% vs 5.7%), the metabolic syndrome (25.7% vs 6.3%), and alanine aminotransferase >30 IU/L (15.6% vs 4.5%) was found (all P < .05). CONCLUSIONS: Overweight/obesity and cardiometabolic risk factors were highly prevalent in a pediatric cohort with T1DM. Hypertension, the metabolic syndrome, and high alanine aminotransferase were significantly more prevalent in overweight/obese compared with normal-weight children with T1DM.

Myeloperoxidase: a useful biomarker for cardiovascular disease risk stratification?

BACKGROUND: Inflammation and oxidative stress are associated with atherosclerosis. Myeloperoxidase (MPO) is linked to both inflammation and oxidative stress by its location in leukocytes and its role in catalyzing the formation of oxidizing agents. Recent evidence suggests that MPO activity precipitates atherogenesis. Measurement of MPO in plasma may therefore contribute to cardiovascular disease (CVD) risk stratification. CONTENT: Cross-sectional studies, case-control studies, and prospective-cohort studies investigating the relation between MPO and CVD have been evaluated. Differences in study populations, sample materials, sample handling, and assays were ascertained. Potential causal mechanisms linking MPO to accelerated atherosclerosis are discussed here. A majority of studies indicate that measurement of MPO in plasma was associated with improved CVD risk stratification above and beyond risk stratification results obtained with markers used in routine clinical practice. However, comparison of these epidemiological studies with regard to MPO and outcome is hampered because the reported MPO concentration depends on the assay method, sampling material, and preanalytical and analytical procedures. The link between MPO and CVD can, at least partly, be explained by MPO-dependent oxidation of LDL and HDL, subsequently leading to cholesterol accumulation in the arterial wall. Furthermore, MPO may reduce the bioavailability of nitric oxide, resulting in endothelial dysfunction. Finally, MPO destabilizes atherosclerotic plaques. SUMMARY: Increasing evidence suggests that MPO is causally linked to atherosclerosis and its measurement may improve CVD risk estimation. Before MPO can be used in routine clinical practice, however, standardization of sampling and laboratory procedures is needed.

Ethnic differences in cardiometabolic risk profile in an overweight/obese paediatric cohort in the Netherlands: a cross-sectional study.

BACKGROUND: Differences in prevalence of cardiometabolic risk factors between different ethnic groups are largely unknown. We determined the variation in cardiometabolic risk profile according to ethnicity in a cohort overweight/obese Dutch children. METHODS: An oral glucose tolerance test was performed in 516 overweight/obese Dutch children of multi-ethnic origin, attending an obesity out-patient clinic of an urban general hospital (mean age 10.6 +/- 3.2; 55.2% boys). Anthropometric parameters and blood samples were collected, and the prevalence of (components of) the metabolic syndrome (MetS) and insulin resistance were determined in each ethnic group. RESULTS: Major ethnic groups were Dutch native (18.4%), Turkish (28.1%), and Moroccan (25.8%). The remaining group (27.7%) consisted of children with other ethnicities. Turkish children had the highest mean standardized BMI compared to Dutch native children (P < 0.05). As compared to Moroccan children, they had a higher prevalence of MetS (22.8% vs. 12.8%), low HDL-cholesterol (37.9% vs. 25.8%), hypertension (29.7% vs. 18.0%) and insulin resistance (54.9% vs. 37.4%, all P < 0.05). Although Turkish children also had higher prevalences of forementioned risk factors than Dutch native children, these differences were not statistically significant. Insulin resistance was associated with MetS in the Turkish and Moroccan subgroup (OR 6.6; 95%CI, 2.4-18.3 and OR 7.0; 95%CI, 2.1-23.1, respectively). CONCLUSION: In a Dutch cohort of overweight/obese children, Turkish children showed significantly higher prevalences of cardiometabolic risk factors relative to their peers of Moroccan descent. The prospective value of these findings needs to be established as this may warrant the need for differential ethnic-specific preventive measures.

The association of elevated alanine aminotransferase and the metabolic syndrome in an overweight and obese pediatric population of multi-ethnic origin.

We studied the association between alanine aminotransferase (ALT) and features of the metabolic syndrome in a cohort of overweight and obese children aged 3-18 years. An oral glucose tolerance test was performed in 443 consecutive children from an obesity out-patient clinic (median age 11.2, range 3.1-18.0 years; n=240 boys) of multi-ethnic origin. The prevalence of the metabolic syndrome, insulin resistance, elevated ALT (>30 IU/L), and the association of ALT with (components of) the metabolic syndrome was assessed. The metabolic syndrome was present in 26.9%. Elevated ALT levels were found in 20.3%, with a higher prevalence in boys than in girls (25.8% versus 13.8%, P<0.001). ALT was associated with the prevalence of the metabolic syndrome, insulin resistance, high triglycerides, and low HDL-cholesterol after adjustment for gender, age, and BMI. In conclusion, elevated ALT levels were highly prevalent and associated with the metabolic syndrome, insulin resistance, high triglycerides, and low HDL-cholesterol in an obese multiethnic pediatric population.

Comparison of two consecutive fat-rich and carbohydrate-rich meals on postprandial myeloperoxidase response in women with and without type 2 diabetes mellitus.

Patients with type 2 diabetes mellitus (DM2) have an increased risk of cardiovascular disease (CVD). Myeloperoxidase (MPO), expressed in leukocytes and released upon activation, is associated with CVD and endothelial dysfunction. Postprandial leukocyte recruitment and activation with subsequent MPO release may contribute to atherosclerosis and CVD. We hypothesized that MPO may increase in the postprandial state because of postprandial leukocyte recruitment and/or activation, especially in subjects with DM2. One hundred postmenopausal women, aged 50 to 65 years (66 with normal glucose metabolism [NGM] and 34 with DM2), received 2 consecutive fat-rich meals and 2 consecutive carbohydrate-rich meals on separate occasions. Blood samples were taken before (t = 0) and at 2, 4, and 8 hours after breakfast; lunch was given at t = 4. Plasma MPO concentration was measured by sandwich enzyme-linked immunosorbent assay. The number of leukocytes in fasting blood samples was higher in DM2 compared with NGM (6.1 +/- 1.4 and 5.4 +/- 1.2 x 10(9)/L, respectively; P < .05). Baseline MPO concentration did not significantly differ between NGM and DM2 (51.4 +/- 12.9 and 54.5 +/- 18.4 mug/L, respectively; P = .39). Baseline MPO was positively associated with leukocytes (r = 0.20, P < .05) and inversely associated with high-density lipoprotein cholesterol (r = -0.22, P < .05). Leukocytes increased from 5.0 +/- 1.5 to 6.1 +/- 1.5 x 10(9)/L and from 5.8 +/- 1.4 to 6.6 +/- 1.4 x 10(9)/L in NGM and DM2, respectively (both P < .01), after the fat-rich meals. In contrast to our hypothesized increase in MPO, we found a significant decrease in MPO in NGM (both meal types) and DM2 (fat-rich meals only). Our findings provide no support to our initial hypothesis that meal-induced release of MPO might be a mechanism that contributes to CVD risk.

The Relation Between Thyroid Function and Anemia: A Pooled Analysis of Individual Participant Data.

Context: Anemia and thyroid dysfunction often co-occur, and both increase with age. Human data on relationships between thyroid disease and anemia are scarce. Objective: To investigate the cross-sectional and longitudinal associations between clinical thyroid status and anemia. Design: Individual participant data meta-analysis. Setting: Sixteen cohorts participating in the Thyroid Studies Collaboration (n = 42,162). Main Outcome Measures: Primary outcome measure was anemia (hemoglobin <130 g/L in men and <120 g/L in women). Results: Cross-sectionally, participants with abnormal thyroid status had an increased risk of having anemia compared with euthyroid participants [overt hypothyroidism, pooled OR 1.84 (95% CI 1.35 to 2.50), subclinical hypothyroidism 1.21 (1.02 to 1.43), subclinical hyperthyroidism 1.27 (1.03 to 1.57), and overt hyperthyroidism 1.69 (1.00 to 2.87)]. Hemoglobin levels were lower in all groups compared with participants with euthyroidism. In the longitudinal analyses (n = 25,466 from 14 cohorts), the pooled hazard ratio for the risk of development of anemia was 1.38 (95% CI 0.86 to 2.20) for overt hypothyroidism, 1.18 (1.00 to 1.38) for subclinical hypothyroidism, 1.15 (0.94 to 1.42) for subclinical hyperthyroidism, and 1.47 (0.91 to 2.38) for overt hyperthyroidism. Sensitivity analyses excluding thyroid medication or high levels of C-reactive protein yielded similar results. No differences in mean annual change in hemoglobin levels were observed between the thyroid hormone status groups. Conclusion: Higher odds of having anemia were observed in participants with both hypothyroid function and hyperthyroid function. In addition, reduced thyroid function at baseline showed a trend of increased risk of developing anemia during follow-up. It remains to be assessed in a randomized controlled trial whether treatment is effective in reducing anemia.

Alanine aminotransferase predicts coronary heart disease events: a 10-year follow-up of the Hoorn Study.

Alanine aminotransferase (ALT) is a marker of non-alcoholic fatty liver disease (NAFLD) and predicts incident type 2 diabetes mellitus (DM2). Recently, ALT was shown to be also associated with endothelial dysfunction and carotid atherosclerosis. We studied the predictive value of ALT for all-cause mortality, incident cardiovascular disease (CVD) and coronary heart disease (CHD) events in a population-based cohort of Caucasian men and women aged 50-75 years, at baseline. The 10-year risk of all-cause mortality, fatal and non-fatal CVD and CHD events in relation to ALT was assessed in 1439 subjects participating in the Hoorn Study, using Cox survival analysis. Subjects with prevalent CVD/CHD and missing data were excluded. As compared with the first tertile, the age- and sex-adjusted hazard ratios (95% confidence intervals) for all-cause mortality, CVD events and CHD events were 1.30 (0.92-1.83), 1.40 (1.09-1.81) and 2.04 (1.35-3.10), respectively, for subjects in the upper tertile of ALT. After adjustment for components of the metabolic syndrome and traditional risk factors, the association of ALT and CHD events remained significant for subjects in the third relative to those in the first tertile, with a hazard ratio of 1.88 (1.21-2.92) and 1.75 (1.12-2.73), respectively. In conclusion, the predictive value of ALT for coronary events, seems independent of traditional risk factors and the features of the metabolic syndrome in a population-based cohort. Further studies should confirm these findings and elucidate the pathophysiological mechanisms.

[A woman with shortness of breath and butterfly shaped cell nuclei]. / Een benauwde vrouw met vlinderkernen in het bloed.

A 53-year-old woman with respiratory discomfort came to the Emergency Department. The blood smear, made because of a new thrombocytopenia, showed leukocytes with butterfly-shaped nuclei and fine cytoplasmic granulation. The diagnosis 'microgranular variant of acute promyelocytic leukemia' was made.

Haemoglobin A1c: Historical overview and current concepts.

Since the discovery of the relation between increased concentrations of fast haemoglobin fractions in patients with diabetes mellitus compared to concentrations in subjects without diabetes mellitus by Samuel Rahbar and co-workers in 1969, glycated haemoglobin A1c (HbA1c) has become a "gold standard" for glucose management in patients with diabetes mellitus. Recently, HbA1c has been advocated as a diagnostic marker for diabetes mellitus, which further underlines the importance of HbA1c. There are currently more than 30 methods available on the market with an analytical performance ranging from poor to state of the art. This review describes the biochemistry of HbA1c and the concepts of analytical and biological variation with respect to the measurement of HbA1c. Subsequently, aspects regarding the discovery of HbA1c are described. In addition, an overview is given on the assays methods that are currently available for the measurement of HbA1c. Finally, recommendations for the minimally required analytical performance characteristics of the current HbA1c assays are presented.

Thyroid hormones and erythrocyte indices in a cohort of euthyroid older subjects.

OBJECTIVES: Hypothyroidism is associated with normocytic anaemia. Indeed, a limited number of studies have shown significant associations between free thyroxin (T4) and erythrocyte indices. These studies did not include vitamin B12, folic acid, iron and renal function in the analyses. We therefore studied the association between thyroid hormones and erythrocyte indices in a population-based cohort of older euthyroid subjects, with adjustment for major confounding parameters. DESIGN: Data, including thyroid hormones and erythrocyte indices, are from the Longitudinal Aging Study Amsterdam (LASA), an ongoing cohort study on predictors and consequences of changes in health in the ageing population in the Netherlands. Multivariable linear regression analyses were applied to study the cross-sectional associations between free T4, thyroid stimulating hormone (TSH) and erythrocyte indices (haemoglobin content, haematocrit, mean cell volume (MCV) and erythrocyte count) in a euthyroid sub-sample. The final models were adjusted for vitamin B12, folic acid, iron levels and renal function. RESULTS: In 708 euthyroid older subjects, an increase of 5pmol/L free T4 was associated with a mean increase of 0.12mmol/L or 0.19g/dL of haemoglobin, 0.068 10(12)/L erythrocytes and 0.006L/L haematocrit (P=0.007, P=0.005, P=0.001, respectively). Free T4 was not significantly associated with MCV (P>0.05). TSH appeared not to be associated with any of the erythrocyte indices (all P>0.05). CONCLUSIONS: In a cohort of older subjects, free T4, but not TSH, was associated with erythrocyte indices, confirming the role of thyroid hormones in the regulation of erythropoiesis.

A patient with a prolonged activated partial thromboplastin time and a deep intracerebral haemorrhage.

We report on a 57-year-old woman with a pontine haemorrhage and an extremely prolonged activated partial thromboplastin time (aPTT) of more than 240 s, suggestive of a coagulation disorder. Given the location of the haemorrhage, which is associated with a high mortality rate, recombinant factor VIIa was administered, although not all necessary laboratory analyses could be performed at that time. In our case, a deficiency of factor XII was found, which is not associated with an increased bleeding risk. In an acute setting, evaluation of a prolonged aPTT may cause diagnostic and therapeutic challenges, in particular in situations where additional laboratory investigations may not be readily available.

Implementation of flow cytometry in the diagnostic work-up of myelodysplastic syndromes in a multicenter approach: report from the Dutch Working Party on Flow Cytometry in MDS.

Flow cytometry (FC) is recognized as an important tool in the diagnosis of myelodysplastic syndromes (MDS) especially when standard criteria fail. A working group within the Dutch Society of Cytometry aimed to implement FC in the diagnostic work-up of MDS. Hereto, guidelines for data acquisition, analysis and interpretation were formulated. Based on discussions on analyses of list mode data files and fresh MDS bone marrow samples and recent literature, the guidelines were modified. Over the years (2005-2011), the concordance between the participating centers increased indicating that the proposed guidelines contributed to a more objective, standardized FC analysis, thereby ratifying the implementation of FC in MDS.