CKM and hypertrophic cardiomyopathy: Among them, only 1 newborn with CK-MM at 470 ng/mL (Fig. 1 and 2), approximately at the 95th percentile of the newborn range, had the lowest GAA activity in DBS, and was confirmed as a patient with classical IOPD due to the presence of hypertrophic cardiomyopathy.