Retrospective Study of Klinefelter Syndrome in Chinese Boys

Background: Klinefelter syndrome (KS) is a common but under-recognised condition caused by an additional X chromosome in the phenotypic male. Clinical features are non-specific and thus many patients remain undiagnosed until adulthood. Persistent androgen deficiency in KS patients may result in cardiovascular complications and has fertility implications, thus warranting earlier detection. Subjects: Nine Chinese boys with karyotype-confirmed non-mosaic Klinefelter syndrome. Methods: Retrospective review of the clinical features at presentation, baseline hormonal investigations and the treatment response was conducted. Results: The mean age at presentation was 14.3 years old. Six patients (66.7%) were referred to us from Student Health Service. Six patients (66.7%) had height percentile more than the 50th height percentile. Only two (22.2%) had gynaecomastia. All had pubic hair bit with a testicular volume of <3 ml on each side. All had elevated gonadotropins but the degree of hypogonadism was variable. All patients reported morning erection after treatment. Conclusion: Our report is the first study reviewing KS in Chinese children. The clinico-hormonal features at presentation were similar to that in Western series, except, gynaecomastia was not as common. Early recognition of KS is important to facilitate timely treatment and family planning. Student Health Service plays an important role in screening for KS.