[Neonatal screening for congenital hypothyroidism: more than 30 years of experience in the Netherlands].

Objective: To describe the Dutch neonatal screening programme for congenital hypothyroidism (CH).

Design: Descriptive study.

Method: Data on neonatal screening for CH in the period 1 January 1981 through 31 December 2011 were obtained from the Department for Vaccine Supply and Prevention Programmes of the Dutch National Institute for Public Health and the Environment (RIVM), laboratories and paediatricians to whom babies with abnormal screening results were referred.

Cost-effectiveness of newborn screening for cystic fibrosis determined with real-life data.

Background: Previous cost-effectiveness studies using data from the literature showed that newborn screening for cystic fibrosis (NBSCF) is a good economic option with positive health effects and longer survival.

Methods: We used primary data to compare cost-effectiveness of four screening strategies for NBSCF, i.e.

Evolution of an influenza pandemic in 13 countries from 5 continents monitored by protein microarray from neonatal screening bloodspots.

Background: Because of lack of worldwide standardization of influenza virus surveillance, comparison between countries of impact of a pandemic is challenging. For that, other approaches to allow internationally comparative serosurveys are welcome.

Objectives: Here we explore the use of neonatal screening dried blood spots to monitor the trends of the 2009 influenza A (H1N1) pdm virus by the use of a protein microarray.

Decline of IgG pertussis toxin measured in umbilical cord blood, and neonatal and early infant serum.

Maternal pertussis-specific antibodies are passively acquired by infants during pregnancy. An IgG pertussis toxin (IgG-PT) concentration of >20 U/ml is considered to protect neonates against pertussis. To evaluate the IgG concentration at birth and during the first two months of life, we examined the IgG-PT concentration in the umbilical cord blood and three times during the neonatal and early infant period.

Newborn screening for hunter disease: a small-scale feasibility study.

Hunter disease (Mucopolysaccharidosis type II, MPS II) is an X-linked lysosomal storage disorder caused by deficiency of iduronate-2-sulfatase (IDS). Two main therapies have been reported for MPS II patients: enzyme-replacement therapy (ERT) and hematopoietic stem-cell transplantation (HSCT). Both treatment modalities have been shown to improve some symptoms, but the results with regard to cognitive functioning have been poor.

Antibody levels against B. pertussis in neonates measured in dried blood spots.

Aim: We designed this study to investigate if immunoglobuline G-Pertussis toxin (IgG-PT) against Bordetella pertussis in umbilical cord blood can reliably be determined in dried blood spots on filter paper (Guthrie) cards.

Patients And Methods: We prospectively included 129 mothers and their newborns born in a general hospital in the Netherlands. The relation between IgG-PT against B.

Relationship between neonatal screening results by HPLC and the number of α-thalassaemia gene mutations; consequences for the cut-off value.

Objectives: To evaluate the relationship between FAST peak percentage by adapted Bio-Rad Vnbs analysis using the valley-to-valley integration and genotypes with the aim to improve differentiation between severe α-thalassaemia forms (HbH disease) and the milder disease types.

Method: DNA analysis for α-thalassaemia was performed on 91 dried blood spot samples presenting normal and elevated FAST peak levels, selected during three years of Dutch national newborn screening.

Results: Significant differences were found between samples with and without α-thalassaemia mutations, regardless of the genetic profiles.

Pertussis disease burden in the household: how to protect young infants.

Background: We conducted a population-based, nation-wide, prospective study to identify who introduced pertussis into the household of infants aged 6 months admitted to the hospital for pertussis in the Netherlands.

Methods: During the period 2006-2008, a total of 560 household contacts of 164 hospitalized infants were tested by polymerase chain reaction, culture, and serological examination to establish Bordetella pertussis infection. Clinical symptoms and vaccination history were obtained by a questionnaire submitted during sample collection and 4-6 weeks afterwards.

Quality of nuchal translucency measurements in The Netherlands: a quantitative analysis.

Objective: The Dutch Centre for Population Research has specified quality demands for nuchal translucency (NT) measurement in The Netherlands. We performed an analysis of the quality of NT measurement in 2005-2006 and its influence on screening performance.

Methods: This was a retrospective study of records of NT measurements (n = 27,738) obtained between January 2005 and December 2006 retrieved from the Dutch National Institute for Public Health and the Environment (RIVM).

First-trimester Down syndrome screening performance in the Dutch population; how to achieve further improvement?

Objective: To study the performance of the first-trimester combined test between 2004 and 2006 compared to a previous period to investigate changes in time and identify reasons for sub-optimal performance.

Methods: Serum samples were analysed for pregnancy-associated plasma protein A (PAPP-A) and the free beta subunit of human chorionic gonadotrophin (f beta-hCG). Nuchal translucency (NT) was measured between 10 and 14 weeks.

Lack of standardization in determining gestational age for prenatal screening.

Objectives: To determine whether estimation of gestational age (GA) in the context of first-trimester Down syndrome screening is standardized in the Netherlands.

Methods: This was a retrospective study, carried out between January 2005 and December 2006, of women who underwent first-trimester Down syndrome screening (n = 40,730) based on GA, maternal serum analysis and nuchal translucency (NT) measurement. Date of the last menstrual period (LMP), dating scan information including measurement of crown-rump length (CRL), NT thickness and name of the sonographer were recorded for all pregnancies.

First ISNS Reference Preparation for Neonatal Screening for thyrotropin, phenylalanine and 17alpha-hydroxyprogesterone in blood spots.

Background: Neonatal screening for congenital disorders like phenylketonuria (PKU), congenital hypothyroidism (CH) and congenital adrenal hyperplasia (CAH) is generally performed in dried blood spots on filter paper. The analytes of interest for testing for PKU, CH and CAH are phenylalanine, thyrotropin (TSH) and 17alpha-hydroxyprogesterone (17OHP), respectively. The International Society for Neonatal Screening (ISNS) decided to prepare a combined reference preparation for the three analytes on filter paper Schleicher & Schuell #903, Whatman BFC180 and Toyo Roshi 545.

Multi-centre first-trimester screening for Down syndrome in the Netherlands in routine clinical practice.

Objectives: This is the first report on the results of a first-trimester combined-test screening programme in the Netherlands in a multi-centre routine clinical setting.

Methods: Between July 2002 and May 2004, blood samples were taken from subjects in 44 centres in the Netherlands and sent to our laboratory to assay for maternal serum concentrations of fbeta-hCG and PAPP-A. Fetal nuchal translucency (NT) was measured in the participating centres at a gestational age (GA) of 10-14 weeks.

Subacute toxicity of alpha-ergocryptine in Sprague-Dawley rats. 2: metabolic and hormonal changes.

The present study describes the metabolic changes observed in a dietary subacute toxicity experiment with the ergot alkaloid alpha-ergocryptine in Sprague-Dawley rats. The observed effects on metabolic and hormonal parameters were described separately from the general toxicological effects, in view of the important role of dopamine agonists in metabolism (e.g.

Specificity and sensitivity of high levels of immunoglobulin G antibodies against pertussis toxin in a single serum sample for diagnosis of infection with Bordetella pertussis.

Laboratory confirmation of pertussis by culture, PCR, or detection of antibody increase in paired sera is hampered by low sensitivity in the later stages of the disease. Therefore, we investigated whether, and at which level, concentrations of immunoglobulin G (IgG) antibodies against pertussis toxin (PT), IgG-PT, in a single serum sample are indicative of active or recent pertussis. IgG-PT, measured by enzyme-linked immunosorbent assay in units per milliliter, was analyzed in 7,756 sera collected in a population-based study in The Netherlands, in the sera of 3,491 patients with at least a fourfold increase of IgG-PT, in paired sera of 89 patients with positive cultures and/or PCR results, and in the sera of 57 patients with clinically documented pertussis with a median follow-up of 1.

Preparation of the first European working standard for phenylalanine determination in dried blood spots.

Objective: To develop a standard preparation for measurement of phenylalanine in blood spots in phenylketonuria against which manufacturers of kits for phenylalanine determination could calibrate their own blood spot calibrators.

Methods: As most of the variation of phenylalanine concentration in dried blood spots is due to the way the blood spot calibrators are prepared, a minimum set of prerequisites for the preparation of blood spot calibrators was established by a group of scientific experts and manufacturers. A "European working standard for phenylalanine in blood spots" (EWS-Phe-01) was prepared and distributed to manufacturers taking part in this project.

The need for standardized bloodspot TSH-calibrators in congenital hypothyroidism screening.

Introduction: The preparation of bloodspot calibrators and quality control samples for neonatal thyrotropin (TSH), as part of the national quality assessment scheme in The Netherlands, is sometimes problematic. Often, the recovery of the added TSH is well above 100% when measured in plasma. Results from other External Quality Assessment Schemes for neonatal TSH show similar problems.

Comparison of six radioimmunoassay kits for human follitropin in serum.

Six commercially available radioimmunoassay (RIA) kits for human follitropin (follicle-stimulating hormone; hFSH) were compared with respect to precision, "accuracy", specificity and performance. The intra- and interassay coefficients of variation ranged from 4.7 to 8.

Early detection of pregnancy in rhesus and stump-tailed macaques (Macaca mulatta and Macaca arctoides). Evaluation of two radioimmunoassays and a hemagglutination inhibition test.

Chorionic gonadotropin (mCG) in serum and urine of monkeys was determined by a radioimmunoassay and hemagglutination inhibition (HAI subhuman primate tube test for pregnancy). HAI-positive pregnancy tests coincided fully with the mCG excretion patterns as determined by RIA (oLH beta system). The least reliable system was the hCG-beta RIA.

A radioimmunoassay for pregnancy associated protein, beta 1SP1: levels in pregnancy, trophoblastic and neoplastic disease.

A radioimmunoassay system for the glycoprotein beta 1SP1, one of the pregnancy-associated proteins, has been set up. beta 1SP1 levels in normal pregnancy have been established transversally. Clearance (t1/2) from the circulation postpartum ranged from 1.