Survey of scope of neonatal screening in the United Kingdom

Risk of Invasive Pneumococcal Disease in Children with Sickle Cell Disease in England: A National Observational Cohort Study, 2010-2015

OBJECTIVE

To describe the clinical presentation, risk factors, serotype distribution and outcomes of invasive pneumococcal disease (IPD) in children with sickle cell disease (SCD) following the introduction of the 13-valent pneumococcal conjugate vaccine (PCV13) in the UK.

DESIGN

Prospective national newborn screening for SCD and enhanced national IPD surveillance.

PARTICIPANTS

Children with SCD born in England between 1 September 2010 and 31 August 2014 who developed laboratory-confirmed IPD by 31 December 2015.

MAIN OUTCOMES AND MEASURES

Risk of IPD in children with SCD compared with children without SCD during the surveillance period.

RESULTS

Eleven children homozygote for haemoglobin S (HbSS) and one double heterozygote for haemoglobin S and C (HbSC) developed IPD. Septicaemia (n=7) and lower respiratory tract infection (n=4) were the main clinical presentations, and serogroup 15 (not present in PCV13) was responsible for 73% (8/11) of cases. Three children with HbSS (27%) died compared with <5% nationally. Children with HbSS had a 49-fold (95% CI 27 to 89, P<0.001) higher risk of IPD compared with their peers without SCD.

CONCLUSIONS

Children with SCD remain at increased risk of IPD despite national newborn screening, early penicillin prophylaxis and high pneumococcal vaccine uptake. They are also more likely to die of their infection compared with their peers without SCD. Most IPD cases are now due to serotypes not covered by PCV13. Healthcare professionals need to work more closely with families with SCD and local communities to emphasise the importance of penicillin prophylaxis, explore barriers, allay misguided beliefs and facilitate rapid access to healthcare.

Newborn bloodspot screening in the UK – past, present and future

Screening newborn babies for inherited metabolic disease began in the UK in the late 1950s with the ‘nappy test’ for phenylketonuria. In 1969 the Department of Health recommended changing to bloodspot screening using the techniques developed in the USA by Robert Guthrie and his associates. Bloodspot screening for various other disorders (galactosaemia, maple syrup urine disease, homocystinuria, cystic fibrosis and others) was introduced on a patchy local basis but, until 2000, the only additional disorder officially recommended was congenital hypothyroidism. Screening for haemoglobinopathies received official support in 2000 and for cystic fibrosis in 2001 though implementation was slow, particularly for the latter. Both these screens have raised difficult issues relating to genetic privacy and the detection of carrier status in children. During the last decade screening has become increasingly subject to central control. Though a more consistent and systematic approach was clearly needed, this has undoubtedly slowed the rate of innovation. In particular the UK has lagged behind many other European countries in the application of tandem mass spectrometry (MS-MS) though, following a major pilot study, screening for medium-chain acyl-CoA dehydrogenase deficiency is now in the process of introduction. Attempts to codify clinical and laboratory procedures have also proved controversial, highlighting marked differences in practice in various parts of the country and the difficulty of rationalizing these within a practicable and scientifically justified framework. Notwithstanding this, there are many positive developments and newborn screening remains a stimulating and rewarding field in which to work.

Ideas about heredity, genetics, and 'medical genetics' in Britain, 1900-1982

The aim of this paper is to understand how evolving ideas about heredity and genetics influenced new medical interests and practices and, eventually, the formation of 'medical genetics' as a medical specialism in Britain. I begin the paper by highlighting the social and institutional changes through which these ideas passed. I argue that, with time, there was a decisive convergence in thought that combined ideas about the familial aspects of heredity and the health needs of populations with an omnibus 'genetic' approach to health and illness that focused on the structures and activities of chromosomes and genes in individuals. I show how this convergence in thought was spurred on, first, by innovations in genetic science and technology in the years after 1960, and, second, by negotiated protocols and standards of medical practice worked out by bodies such as the relevant royal colleges, the linked associations and societies for medical professionals, affected training and research authorities, and the state. The notion of 'medical genetics' in Britain consequently gained a semblance of unanimity over its basic reference points and arrived at a meaning directly tributary to current acceptance of the term in the context of a medical specialism.

Newborn screening: new developments, new dilemmas

Scientific and technological advances are lending pressure to expand the scope of newborn screening. Whereas this has great potential for improving child health, it also challenges our current perception of such programmes. Standard newborn screening programmes are clearly justified by the fact that early detection and treatment of affected individuals avoids significant morbidity and mortality. However, proposals to expand the scope and complexity of such testing are not all supported by a similar level of evidence for unequivocal benefit. We argue that screening for genetic susceptibility to complex disorders is inherently different from standard screening and, while of potential value, must be considered separately from conventional testing.

Arguments for early screening: a clinician's perspective

Recent technological advances have led to an expansion in inborn errors that can be detected in the newborn period. Further developments in newborn screening will increase this number further. There are two main arguments put forward to support the developments of an expanded newborn screening programme. Firstly there may be an improvement in patient outcome. The early detection of disorders either in the pre-symptomatic or early symptomatic phase should, with treatment, result in the prevention of severe illness. This is evident for phenylketonuria and generally accepted for homocystinuria and medium-chain acyl-CoA dehydrogenase deficiency, disorders which have a long pre-symptomatic phase. However, other inborn errors may present within the first 10 days of life with severe illness, particularly neonatal encephalopathy. In order to effectively stop the rapid progression of these disorders, screening must be undertaken early although where severe metabolic decompensation occurs within 2 to 3 days of birth, newborn screening programmes are unlikely to be of direct benefit. Secondly an early diagnosis, even when this does not affect that individual's prognosis, may allow for accurate genetic advise to be given to the family and the opportunity to have prenatal diagnosis for future pregnancies.

CONCLUSION

For the clinician, the introduction of an expanded and early newborn screening presents opportunities for improved patient and family care. However, it is important to be aware of possible detrimental effects on families of early screening. Screening tests must have adequate sensitivity and high specificity. Furthermore with early screening, close liaison between the laboratory, clinicians and community services is essential.

Audit of neonatal screening programme for phenylketonuria and congenital hypothyroidism

The performance of the neonatal screening programme was audited against clinical standards in the Bath clinical area from 1 April 1994 to 31 March 1996. The standards and policy were agreed by local service provider representatives of the screening and were audited, using laboratory and child health computer systems and medical records. Two annual reports were produced with recommendations for improvement communicated to representatives of the service. Thus the first audit loop has been completed. The audit shows that the coverage of the service is excellent, with all eligible babies being offered screening; those with congenital hypothyroidism or phenylketonuria receive appropriate treatment by the 28 day standard. The process works extremely well, although areas for improvement have been identified, to increase the efficiency of the service. It is concluded that an effective and efficient audit cycle can be established, to monitor and improve the performance of the neonatal screening service.

Impact of incomplete coverage of neonatal dried blood spot screening on estimating HIV-1 seroprevalence

The aim of this study was to determine the extent to which selective under-coverage of births to mothers more likely to be at risk of HIV-1 infection will result in a significant under-estimation of the true neonatal seroprevalence. Census data, local birth statistics, maternity data and data from the prevalence monitoring programme were used to produce a model to predict the effects of under-coverage in the uptake of neonatal metabolic screening which has been observed in babies with a mother of ethnic group black African. The adjustment factor which allows for under-coverage is the relative inclusion ratio (RIR); the probability that samples from a group at different risk of HIV infection were included in the survey divided by the probability of inclusion for samples from all other babies. The RIR was found to be close to unity (0.97), indicating a minimal bias. Under usual conditions only if the relative inclusion ratio (RIR) declined to values of 0.87 or below would there be a substantial bias. Despite some selective under representation, the results obtained from the Unlinked Anonymous HIV Monitoring Programme Dried Blood Spot Survey would seem to identify levels of prevalence in the population of child-bearing women with a good degree of accuracy and remains a useful tool for resource allocation, planning of services, provision of care and counselling.