Counting Conditions on Newborn Bloodspot Screening Panels in Australia and New Zealand.

A greater number of screened conditions is often considered to equate to better screening, whereas it may be due to conditions being counted differently. This manuscript describes a harmonised Australasian approach to listing target conditions found on bloodspot screening panels. Operational definitions for target disorders and incidental findings were developed and applied to disorder lists.

The use of liquid chromatography-tandem mass spectrometry in newborn screening for congenital adrenal hyperplasia: improvements and future perspectives.

Newborn screening for congenital adrenal hyperplasia using 17-hydroxyprogesterone by immunoassay remains controversial despite screening been available for almost 40 years. Screening is confounded by poor immunoassay specificity, fetal adrenal physiology, stress, and illness which can result in a large number of false positive screening tests. Screening programmes apply higher screening thresholds based on co-variates such as birthweight or gestational age but the false positive rate using immunoassay remains high.

The risk of classical galactosaemia in newborns with borderline galactose metabolites on newborn screening.

Newborn screening (NBS) for classical galactosaemia (CG) facilitates early diagnosis and treatment to prevent life-threatening complications, but remains controversial, and screening protocols vary widely between programmes. False-negatives associated with first-tier screening of total galactose metabolites (TGAL) are infrequently reported; however, newborns with TGAL below the screening threshold have not been systematically studied. Following the diagnosis of CG in two siblings missed by NBS, a retrospective cohort study of infants with TGAL just below the cut-off (1.

The impact of prolonged, maternal iodine exposure in early gestation on neonatal thyroid function.

Context: Hysterosalpingography (HSG) using oil-soluble contrast medium (OSCM) improves pregnancy rates but results in severe and persistent iodine excess, potentially impacting the fetus and neonate.

Objective: To determine the incidence of thyroid dysfunction in newborns conceived within six months of OSCM HSG.

Design: Offspring study of a prospective cohort of women who underwent OSCM HSG.

Evaluation of a New Laboratory Protocol for Newborn Screening for Congenital Adrenal Hyperplasia in New Zealand.

Between 2005 and 2021, 49 cases of classical congenital adrenal hyperplasia were diagnosed in New Zealand, 39 were detected in newborns and 10 were not detected by screening. Currently, for every case of CAH detected by screening, 10 false-positive tests are encountered. Second-tier liquid chromatography-tandem mass spectrometry (LCMSMS) has the potential to improve screening sensitivity and specificity.

Fifty years of newborn screening for congenital hypothyroidism: current status in Australasia and the case for harmonisation.

Objectives: Since its implementation 50 years ago in Quebec, Canada, newborn screening for congenital hypothyroidism has become one of the most successful public health measures worldwide. Screening programmes across Australia and New Zealand are characterised by significant commonalities in screening algorithms, and a high degree of regional cooperation in harmonisation efforts. We aimed to conduct a comprehensive survey of current performance and practices related to the total testing process for congenital hypothyroidism screening and provide recommendations for harmonisation priorities within our region.

Genotype-phenotype correlations in CPT1A deficiency detected by newborn screening in Pacific populations.

Carnitine palmitoyltransferase 1A (CPT1A) deficiency is a long chain fatty acid oxidation disorder, typically presenting with hypoketotic hypoglycaemia and liver dysfunction during fasting and intercurrent illness. Classical CPT1A deficiency is a rare disease, although a milder 'Arctic variant' (p.P479L) is common in the Inuit population.

Introducing Newborn Screening for Severe Combined Immunodeficiency-The New Zealand Experience.

Screening for severe combined immunodeficiency (SCID) was added to the New Zealand national newborn screening programme in December 2017. Documentation pertaining to the application to add SCID to the panel and screening results over the first three years were reviewed. Screening evaluation metrics were shown to differ according to site of collection (babies in a neonatal intensive care unit vs.

Introduction of a Protocol for Structured Follow-Up and Texting of Inadequate and Borderline-Positive Newborn Metabolic Screening Results.

A national protocol for structured follow-up and texting of repeat newborn bloodspot screening (NBS) sample requests was introduced. Repeat samples are needed where the initial sample is inadequate or the result borderline-positive. This protocol aimed to improve the timeliness and completeness of receipt of repeat NBS samples.

Hysterosalpingography with Oil-Soluble Contrast Medium Does Not Increase Newborn Hypothyroidism.

Objective: Hysterosalpingography (HSG) with oil-soluble contrast medium (OSCM) improves pregnancy rates in women with idiopathic infertility. However, OSCM has high iodine content and slow clearance resulting in potential iodine excess. If pregnancy occurs, this could impact fetal thyroid gland development and function.

Birth Weight- or Gestational Age-adjusted Second-tier LCMSMS Cutoffs Improve Newborn Screening for CAH in New Zealand.

Context: The positive predictive value of newborn screening for congenital adrenal hyperplasia (CAH) in New Zealand is approximately 10%. The use of a second tier liquid chromatography-tandem mass spectrometry bloodspot steroid profile test with birth weight- or gestational age-adjusted screening cutoffs may result in further screening improvements.

Methods: Three years of newborn screening data with additional second-tier steroid metabolites was evaluated (n = 167 672 births).

Implementing steroid profiling by liquid chromatography-tandem mass spectrometry improves newborn screening for congenital adrenal hyperplasia in New Zealand.

Objective: To evaluate the impact of a liquid chromatography-tandem mass spectrometry (LCMSMS) second-tier test on newborn screening for congenital adrenal hyperplasia due to 21-hydroxylase deficiency (CAH) in New Zealand.

Design: In a prospective study, a LCMSMS method to measure 17-hydroxyprogesterone (17OHP) was adapted to measure four additional steroids. Steroid concentrations were collected on all second-tier CAH screening tests while protocols remained unchanged.

It All Depends What You Count-The Importance of Definitions in Evaluation of CF Screening Performance.

Screening metrics are essential to both quality assessment and improvement, but are highly dependent on the way positive tests and cases are counted. In cystic fibrosis (CF) screening, key factors include how mild cases of late-presenting CF and CF screen positive, inconclusive diagnosis (CFSPID) are counted, whether those at prior increased risk of CF are excluded from the screened population, and which aspects of the screening pathway are considered. This paper draws on the New Zealand experience of almost forty years of newborn screening for CF.

Measurement of 17-Hydroxyprogesterone by LCMSMS Improves Newborn Screening for CAH Due to 21-Hydroxylase Deficiency in New Zealand.

The positive predictive value of newborn screening for congenital adrenal hyperplasia due to 21-hydroxylase deficiency was <2% in New Zealand. This is despite a bloodspot second-tier immunoassay method for 17-hydroxyprogesterone measurement with an additional solvent extract step to reduce the number of false positive screening tests. We developed a liquid chromatography tandem mass spectrometry (LCMSMS) method to measure 17-hydroxyprogesterone in bloodspots to replace our current second-tier immunoassay method.

Newborn Screening TSH Values Less Than 15 mIU/L Are Not Associated With Long-term Hypothyroidism or Cognitive Impairment.

Background: It is unclear whether newborns with mild thyrotropin elevation (mTSHe) are at risk of neurocognitive impairment. We assessed whether mTSHe at birth persists during childhood and compared neurocognitive functioning to siblings.

Methods: This study encompassed children born in the Auckland region (New Zealand) with a newborn screen TSH level of 8 to 14 mIU/L blood, age 6.

Plasma ammonia concentrations in extremely low birthweight infants in the first week after birth: secondary analysis from the ProVIDe randomized clinical trial.

Background: Little is known about normative ammonia concentrations in extremely low birthweight (ELBW) babies and whether these vary with birth characteristics. We aimed to determine ammonia concentrations in ELBW babies in the first week after birth and relationships with neonatal characteristics and protein intake.

Methods: Arterial blood samples for the measurement of plasma ammonia concentration were collected within 7 days of birth from ProVIDe trial participants in six New Zealand neonatal intensive care units.

Feasibility study assessing equitable delivery of newborn pulse oximetry screening in New Zealand's midwifery-led maternity setting.

Objectives: The aim of this study was to conduct New Zealand-specific research to inform the design of a pulse oximetry screening strategy that ensures equity of access for the New Zealand maternity population. Equity is an important consideration as the test has the potential to benefit some populations and socioeconomic groups more than others.

Setting: New Zealand has an ethnically diverse population and a midwifery-led maternity service.

Pulse oximetry screening in a midwifery-led maternity setting with high antenatal detection of congenital heart disease.

Aim: To assess local and individual factors that should be considered in the design of a pulse oximetry screening strategy in New Zealand's midwifery-led maternity setting.

Methods: An intervention study was conducted over 2 years. Three hospitals and four primary maternity units participated in the study.

The impact of demographic factors on newborn TSH levels and congenital hypothyroidism screening.

Context: Optimal newborn screening thyroid-stimulating hormone (TSH) cut-offs are contentious. Analysis of demographic factors that impact screen TSH levels may help explain international variance and provide guidance to screening programmes.

Objective: To determine the influence of demographic factors on newborn screening TSH levels and screening performance parameters.

The decision to discontinue screening for carnitine uptake disorder in New Zealand.

When screening for carnitine uptake disorder (CUD), the New Zealand (NZ) newborn screening (NBS) service identified infants as screen-positive if they had initial and repeat free carnitine (C0) levels of less than 5.0 μmol/L. Since 2006, the NBS service has identified two infants with biochemical and genetic features consistent with neonatal CUD and nine mothers with features consistent with maternal CUD.

The Risk of Fatty Acid Oxidation Disorders and Organic Acidemias in Children with Normal Newborn Screening.

New Zealand has undertaken expanded newborn screening since 2006. During that period there have been no reported cases of fatty acid oxidation disorders or organic acidemias that have been diagnosed clinically that the screening programme missed. However there may have been patients that presented clinically that were not diagnosed correctly or notified.

Evaluation of the revised New Zealand national newborn screening protocol for congenital hypothyroidism.

Objective: The aim of this study was to assess the performance of the revised New Zealand (NZ) newborn screening TSH cut-offs for congenital hypothyroidism (CHT).

Methods: Screening data over 24 months were obtained from the NZ newborn metabolic screening programme, which utilizes a 2-tier system of direct clinical referral for infants with markedly elevated TSH, and second samples from those with mild TSH elevation. We evaluated the impact of a reduced TSH threshold (50 to 30 mIU/l blood) for direct notification and a lower cut-off (15 to 8 mIU/l blood) applied to second samples and babies older than 14 days.

Antenatal screening for aneuploidy--surveying the current situation and planning for non-invasive prenatal diagnosis in New Zealand.

Aims: To gauge clinical opinion about the current system and possible changes as well as providing a forum for education about Non-Invasive Prenatal Testing (NIPT).

Methods: A series of workshops for doctors and midwives, supported by the National Screening Unit of the Ministry of Health and the Royal Australian and New Zealand College of Obstetricians and Gynaecologists, were held in the main centres of New Zealand. Following a brief education session, a structured evaluation of current screening and future possibilities was undertaken by questionnaire.