A 17-year-old boy with Klinefelter syndrome presenting Marfan syndrome-like clinical features of tall stature, scoliosis, arachnodactyly and subluxation of bilateral elbow joints

摘要

A 17-year-old boy who had been suspected to have Marfan syndrome since childhood was referred for molecular genetic analysis of the mutation of Marfan syndrome-related genes. He was the second child of a 35-year-old father and a 31-year-old mother at his birth at term with a birth weight of 3500 g. There was no family history of tall stature and congenital malformations. The parents did not have tall stature. At referral, he had a body weight of 50 Kg, body height of 190 cm (>97th centile), an arm span of 191 cm and a head circumference of 90 cm. He manifested a long and narrow face, tall stature, scoliosis, arachnodactyly, subluxation of bilateral elbow joints, mild intellectual disability, wry neck, strabismus, esotropia, myopia, equivocal wrist and thumb signs, a small penis and scrotums but no pectus deformity and no congenital heart defects (Fig. 1). Sequence analysis revealed no mutation in the genes of FBN1 and TGFBR2. Simultaneous cytogenetic analysis of the peripheral blood revealed a karyotype of 47,XXY (Fig. 2).