Analysis of mutations in the PIK3CA and FGFR3 genes in verrucous\nepidermal nevus
A three-year old black female patient from Rio de Janeiro presented with diffuse\nhyperchromic macules which were present at birth and became darker and keratotic over\ntime. She was born by vaginal term delivery and presented psychomotor development\ncompatible with her age. Dermatological examination revealed presence of velvety\nhyperchromic papules on the face, neck, trunk, and limbs ( and ). Distribution of the\nlesions follows the Blaschko lines in the posterior area of the trunk (). No other changes were observed on physical\nexamination.\nHistopathological examination of the cervical region showed hyperkeratosis, acanthosis,\nand papillomatosis, which is compatible with verrucous nevus. Genetic analysis of\nperipheral blood and of the skin lesion detected a mutation in the Aa542-545 region of\nthe PIK3CA gene, despite the aspect of deletion. Additional tests will be conducted for\nclarification. For amplification of the Aa542-545 region, we used downstream\n5'CCAGAGGGGAAAAATATGACAAAG3' and upstream 5'CCCTTTCATTTTTCTTTTTTCTTACG'3 primers at the\nfollowing final concentrations of reagents: 1x Buffer, MgCl2 2.5 mM, dNTPs 0.2mM,\nprimers 0.5µM; polymerase 0.03 U/ µL; Sample ~ 100ng. Thermocycling\nconditions were 50ºC for 2 minutes; 95ºC for 10 minutes; 40 cycles of\n95ºC for 30 seconds, 58ºC for 1 minute, 72ºC for 1 minute, and\n72ºC for 10 minutes.\nThe patient is being regularly monitored and using adapalene gel 0.1% on the face,\nshowing little response.