Precocious puberty in Klinefelter syndrome: Non-specific result of neurological deficit?

✍ Scribed by Fryns, Jean-Pierre; Devriendt, Koenraad

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 2 KB
• Volume: 72
• Category: Article
• ISSN: 0148-7299
• DOI: 10.1002/(sici)1096-8628(19971003)72:1<122::aid-ajmg26>3.0.co;2-s

✦ Synopsis

Bertelloni et al. [1996]
reported idiopathic precocious puberty in a boy with Klinefelter syndrome with special emphasis on the longitudinal follow-up of growth pattern. These authors also cited a recent review of the published cases of sexual precocity in Klinefelter syndrome by von Mu ¨hlendahl and Heinrich [1994], who underlined that the association of Klinefelter syndrome with sexual precocity is too frequent (5.5-fold higher than expected) to be considered mere coincidence, and concluded: ''given the possible occurrence of precocious puberty in Klinefelter syndrome, we advise a karyotype analysis in boys with sexual precocity mainly in those who show small rather than enlarged testes.''

During the past 30 years , we have diagnosed 743 males with Klinefelter syndrome and classical 47,XXY karyotype. Sixty-eight (9.1%) were diagnosed before the age of 12 years, and the reason for karyotyping was nonspecific congenital anomalies, minor anomalies, and/or psychomotor delay. Follow-up data on these prepubertal Klinefelter boys were collected at regular intervals, and in two boys precocious puberty was subsequently noted, one of the idiopathic type and another due to a hamartoma of the third ventricle without associated anomalies. In these two boys cytogenetic examination had been performed at the respective age of 1.5 and 2 years because of severe developmental delay, persisting hypotonia, and hypogenitalism with small penis and cryptorchidism. Cytogenetic studies on fibroblast cultures after skin biopsy confirmed the 47,XXY karyotype without mosaicism. FMR-1 molecular studies were normal, and extensive metabolic screening was negative in both males.