Newborn blood-spot (heel-prick) screening

Overview

The heel-prick test taken on day 5 (day 5–8) screens every UK baby for 9 serious but treatable conditions: sickle cell disease, cystic fibrosis, congenital hypothyroidism, and six inherited metabolic diseases — with tyrosinaemia type 1 added more recently. Early detection prevents death and disability.

Recognise

• Sickle cell disease — haemoglobinopathy; start penicillin prophylaxis + pneumococcal vaccination early
• Cystic fibrosis — raised immunoreactive trypsinogen → CFTR mutation testing
• Congenital hypothyroidism (CHT) — untreated → severe LD; thyroxine prevents it
• Inherited metabolic diseases: PKU, MCADD, maple syrup urine disease (MSUD), isovaleric acidaemia (IVA), glutaric aciduria type 1 (GA1), homocystinuria (HCU)

Differentials & how to tell them apart

Investigations

Capillary heel-prick onto a blood-spot card on day 5 (acceptable day 5–8). Positive screen → diagnostic confirmation (e.g. confirmatory TFTs for CHT, sweat test/genotype for CF, plasma amino acids for PKU).

Management

Day-5 heel-prick; positive screen → urgent confirmation and condition-specific treatment

1. 1Offer the blood spot to all babies on day 5. Counsel parents; they may decline individual conditions (except they cannot decline only part of the metabolic panel separately).Gate: A baby who has had a blood transfusion (e.g. preterm) needs the sickle cell screen repeated after the transfusion window
2. 2Positive screen → same-pathway referral for diagnostic confirmation and treatment initiation.

Monitor & prognosis

Ensure result received and acted on; condition-specific follow-up.

Excellent for most when detected early — the entire rationale for screening.