Steroid 21-hydroxylase deficiency (21-OHD) accounts for more than 90% of congenital adrenal hyperplasia. CAH newborn screening, in general, is based on 17-hydroxyprogesterone dosage (17-OHP), however it is complicated by the fact that healthy preterm infants have high levels of 17-OHP resulting in false positive cases. We report on molecular features of a boy born pre-term (GA = 30 weeks; weight = 1,390 g) with elevated levels of 17-OHP (91.2 nmol/L, normal < 40) upon neonatal screening who was treated as having CAH up to the age of 8 months. He was brought to us for molecular diagnosis. Medication was gradually suspended and serum 17-OHP dosages mantained normal. The p.V281 L mutation was found in compound heterozygous status with a group of nucleotide alterations located at the 3′ end intron 4 and 5′ end exon 5 corresponding to the splice site acceptor region. Molecular studies continued in order to exclude the possibility of a nonclassical 21-OHD form. 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