RCPCH supplementary guidance — confirmatory testing and natural-cause differentials

The Royal College of Paediatrics and Child Health publishes supplementary guidance reinforcing its March 2026 updated guidance on expert evidence in neonatal-death prosecutions. The supplementary guidance specifically addresses: confirmatory mass spectrometry for biochemical evidence (the insulin-assay problem), the requirement to consider all natural-cause differentials including NEC, PDA, PPHN and late-onset sepsis (the cumulative-resuscitation and prematurity-trajectory points), and the dextrose-rebound C-peptide confounder identified by the Joint Insulin Report.