A piece of card (with a filter paper like texture) onto which neonatal blood from a heel-prick is impregnated as several discrete spots.
Sometimes referred to as the Guthrie test, but, strictly speaking, this refers to the original test for phenylketonuria. Robert Guthrie suggested that the card have more than one test for anticipated future expansion.
The spots of blood are subsequently extracted and analysed for the purposes of neonatal screening for various conditions, particularly those where early intervention prevents morbidity.
The first condition screened for was phenylketonuria, which remains part of the UK screen, but further conditions added include:
- Congenital hypothyroidism
- Cystic fibrosis (from January 2007)
- Medium chain acyl-CoA dehydrogenase deficiency
- Sickle cell disease
- Homocystinuria (from 2014)
- Maple syrup urine disease (from 2014)
- Glutaric aciduria type 1 (from 2014)
- Isovaleric acidaemia (from 2014)