A new examination of the patient and his similarly affected father, who was initially referred as healthy, led us to suspect LEOPARD syndrome, The diagnosis was then confirmed by the occurrence in both patients of a heterozygous mutation c.1403 C > T, p.(Thr468Met), of PTPN11. Subsequently, the proband was also found to have type-1 Arnold-Chiari malformation in association with syringomyelia. This evidence concerns the gene PTPN11 and Noonan syndrome with multiple lentigines.