These spots light that the neurological manifestations of BH4 deficiency are not due to hyperphenylalaninemia alone (as the median phenylalanine is 361.5 umol/l, upper normal) but also due to neurotransmitter dysfunction, as BH4 is an essential cofactor for other enzymes as tyrosine hydroxylase, tryptophan hydroxylases type 1 and 225. Here, TH is linked to Hyperphenylalaninemia.