Heterophilic antibodies leading to falsely positive D-dimer concentration in an adolescent.

Background: We present the case of a 15-year-old adolescent with suspected pulmonary embolism and repeatedly elevated D-dimer levels.

Key Clinical Question: We aim to determine the cause for elevated D-dimer levels in a patient without venous thromboembolism.

Clinical Approach: When the D-dimer measurement was repeated with different assays, D-dimer levels were within the normal reference interval.

The ektacytometric elongation Index (EI) of erythrocytes, validation of a prognostic, rheological biomarker for patients with sickle cell disease.

Objectives: Validation of the measurement of erythrocyte deformability as a useful prognostic, rheological biomarker for patients with sickle cell disease (SCD).

Methods: The degree of reduced deformability was based on the value of the maximum elongation index (EI ) of the deformability curve of an osmotic gradient ektacytometer. The performance of this technique was analytically and clinically validated by analysing 200 normal subjects and 100 patients with well-documented thalassemia's and Hb variants in relation to their clinical condition.

Serum hepcidin in infants born after 32 to 37 wk of gestational age.

Background: Preterm infants are at risk of iron deficiency (ID). Hepcidin has been suggested as a good additional indicator of ID in preterm infants, next to ferritin.

Methods: In a prospective observational study, we analyzed serum hepcidin in 111 infants born after 32+0 to 36+6 wk gestational age during the first 4 mo of life.

Iron deficiency in the first 6 months of age in infants born between 32 and 37 weeks of gestational age.

Background/objectives: Preterm infants are at risk of iron deficiency (ID). In the Netherlands, preterm infants born after 32 weeks of gestational age (GA) do not receive iron supplementation on a routine basis. We hypothesized that dietary iron intake in these infants might not be sufficient to meet the high iron requirements during the first 6 months of life.

Serum hepcidin measured by immunochemical and mass-spectrometric methods and their correlation with iron status indicators in healthy children aged 0.5-3 y.

Background: The diagnostic use of hepcidin is limited by the absence of standardization and lack of age-specific reference ranges in children in particular. The aim of this study was to determine reference ranges of serum hepcidin in healthy children aged 0.5-3 y using mass spectometry (MS) and a commercial immunochemical (IC) assay, and to investigate its association with other indicators of iron status and inflammation.

The value of Ret-Hb and sTfR in the diagnosis of iron depletion in healthy, young children.

Objectives: Reticulocyte hemoglobin (Ret-Hb) content and soluble transferrin receptor (sTfR) are described as promising biomarkers in the analysis of iron status. However, the value of Ret-Hb and sTfR in the early detection of iron depletion, as frequently observed in children in high-income countries, is unclear. We hypothesized that young children to iron depletion, using the WHO cutoff of ferritin <12 μg/l, would have lower Ret-Hb and higher sTfR concentrations compared to children with a ferritin ⩾level 12 μg/l.

The value of soluble transferrin receptor and hepcidin in the assessment of iron status in children with cystic fibrosis.

Background: The value of ferritin in the diagnosis of iron deficiency is limited in patients with CF since it increases in the presence of inflammation. We hypothesized that the soluble transferrin receptor (sTfR) and hepcidin may provide more information than ferritin in assessing iron status in children with CF.

Methods: We analyzed sTfR and hepcidin in relation to conventional iron status indicators in 49 children with CF.

Prevalence and risk factors of iron deficiency in healthy young children in the southwestern Netherlands.

Objectives: Iron deficiency (ID) and iron deficiency anemia (IDA), during the first years of life, are associated with delayed motor and neurological development. Many studies evaluated iron status without an assessment of an acute-phase protein to identify infection. Because most indicators of iron status are influenced by infection, these data may underestimate the ID prevalence.

Feasibility of nonselective testing for hemoglobinopathies in early pregnancy in The Netherlands.

Objective: To examine the feasibility of standardized hemoglobinopathy (HBP) carrier testing for pregnant women in The Netherlands in addition to the standard anemia screening.

Methods: We assessed the prevalence of HBP in women at the time of the first pregnancy visit using both a prospective cohort (N = 703) and a retrospective series of women selected at random (N = 588). For the purpose of analysis, the population was divided into a high risk and a low risk group for HBP based on maternal ethnicity.