Similarities and differences in key diagnosis, treatment, and management approaches for PAH deficiency in the United States and Europe

Table 1 Testing Recommendations at Time of Diagnosis

	ACMG 2014	EU Guidelines (2017)
Establishing Diagnosis	Plasma amino acid analysis	Highest NBS phe level
Establishing Diagnosis	Phenylalanine/tyrosine ratio	Evaluate for liver disease
BH4 testing for disorders of tetrahydrobiopterin metabolism	Recommended with elevated Phe levels	Recommended with elevated Phe levels and/or neurological findings
	Blood/ urine tests for potential BH4 deficiency diagnoses, if abnormal, reflex to enzyme (ACMG) or rapid sequencing European guidelines
Genotyping	Recommended	Not specified, but may be useful in determining BH4 responsiveness

ISSN: 1750-1172