Abstract

OCTN2 deficiency is a rare metabolic disorder that is present in around 1 in 100,000 babies. The severity of the different types varies widely. The mild type usually does not lead to symptoms and requires no treatment. By contrast, the severe type of OCTN2 deficiency leads to serious health problems. Babies can even die from it.

If the severe type is detected early, symptoms can be prevented altogether with carnitine supplements. That is why it is important that the disorder is detected shortly after birth. The disorder can be detected by looking at the amount of free carnitine (C0) in the baby's blood. Indirect detection has happened through blood spot screening since 2007, when measuring the amount of C0 was included as a quality control test. However, this test lacked usefulness from a quality control perspective and is therefore no longer used for that purpose.

In 2024, the Health Council of the Netherlands recommended adding OCTN2 deficiency to blood spot screening as a separate disorder, so that the severe type could still be detected and treated in babies at an early stage. RIVM has conducted a study to find out whether such an addition is possible and what it would cost. This is known as a feasibility study.

RIVM has concluded that it is technically and organisationally possible to add severe OCTN2 deficiency to newborn blood spot screening. The test to measure the amount of C0 can be used for this. However, this will necessitate some adjustments to the blood spot screening programme, for example to ICT systems, laboratory protocols and communications.

RIVM conducted this study on the instructions of the Ministry of Health, Welfare and Sport. As the Ministry with decision-making authority, it wished to know whether adding the disorder was feasible in practice.