Neonatal Screening for Congenital Metabolic and Endocrine Disorders—Results From Germany for the Years 2006–2018

Abstract

Background: The purpose of neonatal screening is the early detection of congenital metabolic and endocrine disorders that, if untreated, could lead to fatal crises or other long-term adverse sequelae. In Germany, neonatal screening is legally regulated. Quality-assurance reports ("DGNS reports") are created and published annually by the German Society for Neonatal Screening (Deutsche Gesellschaft für Neugeborenen-Screening). Data from the DGNS reports for the years 2006-2018 serve as the basis of the present publication.

Methods: For the years 2006-2018, prevalences were calculated and data on process quality were evaluated.

Results: Among 9 218 538 births, 6917 neonates were identified who had one of the target diseases. The overall prevalence was 75 per 100 000 neonates; the disorders most commonly found were congenital hypothyroidism (30 per 100 000) followed by phenylketonuria (PKU) and medium-chain acyl-CoA dehydrogenase deficiency (MCAD) (10 per 100 000 each). Of the 272 205 follow-up screenings requested, 80% were received. The rate of positive screening findings (recall rate) declined over the observation period, from 0.90% in 2006 to 0.37% in 2018. For every five positive screening findings, one case of a target disorder was confirmed. 79% of the children for whom treatment was indicated began to receive treatment within two weeks.

Conclusion: The low recall rate and the early initiation of treatment in 79% of the affected children indicate that neonatal screening for metabolic and endocrine disorders in Germany is effective. The incorporation of tracking structures and the introduction of a registry could further improve the quality of the program.

Figure 1

Flow chart of neonatal screening in Germany, 2006–2018: The screening process with the cumulative data from the years 2006–2018, showing the numbers of repeat examinations required, confirmed cases, and losses to follow-up * Actual data for 2006–2017; for 2018, estimated on basis of previous years GW, Gestational week

Figure 2

Figure 2

Recall rates for selected target disorders in neonatal screening in Germany from 2006 to 2018 Screening for congenital hypothyroidism, PKU/HPA (phenylketonuria/mild hyperphenylalaninemia) and MCAD deficiency (MCAD, medium-chain aAcyl-CoA dehydrogenase) shows a low recall rate (rate of positive screening results) even without second-tier procedures. In screening for CAH, the introduction of second-tier methods (additional analyses of the same blood sample in a second stage of examination) led to a distinct reduction in recall rate.

eFigure 1

Age at time of blood sampling 2006–2018

eFigure 2

Time from blood sampling to arrival of sample at laboratory

eFigure 3

Time between arrival of sample at laboratory and reporting of result

eFigure 4

Age at initiation of treatment