BCKDK and cystic fibrosis: Other reports have included a review of the first 3 years of screening for CF (and the need to revise the IRT/DNA protocol) and the possibility of NBS for branched chain ketoacid dehydrogenase kinase (BCKDK) deficiency, which is linked to a neurodevelopmental disorder characterized by autism, intellectual disability, and microcephaly [945,946].