Klinefelter syndrome (KS) is defined as “a syndrome of tall stature, eunuchoidal body, gynaecomastia, azospermia and increased FSH”.1 It the most frequent sex chromosome anomaly (47XXY) occurring in 0.2% male-bodied people.2 Hypogonadism may present in childhood, however, 50% remains undiagnosed; the most reliable marker is small testicular volume; features of testicular failure occur from puberty.2 Although transsexualism occurs in 0.4-1.3% of the population,3 the literature reports few cases in patients with KS.4
A 29-year-old male-bodied person was identified on fertility testing as 47XXY karyotype. Puberty had commenced concurrent with the subject’s peers, but the patient did not attain male pubertal maturity. Ten years later testosterone was initiated for hypogonadism. The physical changes from testosterone replacement resulted in significant gender dysphoria. The patient presented requesting oestrogen therapy; it was clear that she had experienced herself as female since childhood. Endocrine assessment prior to transition demonstrated small (4ml) testes, gynaecomastia and low testosterone (6mmol/l) with elevated gonadotrophins (LH12.7IU/l; FSH34.7IU/l). The co-morbidities associated with 47XXY karyotype (e.g. metabolic syndrome, thromboembolic disease, osteoporosis and psychiatric morbidity) were considered when planning medical care.5 Androgen blockade was commenced followed by transdermal oestrogen. The patient has successfully publically affirmed her female sex and continues hormonal therapy; she remains with her female partner and plans reassignment surgery.
This case highlights the inadequacy of the traditional binary concept of sexual differentiation, and the need for a more complex framework.6 Progress in transgender health may be limited by a lack of clear, respectful and appropriate terminology.7 Failure to distinguish issues associated with diversity in gender expression from issues associated with diversity in sexual formation may result in inaccurate medical communication, as well as a loss of legal and human rights, including access to medical treatment.8 The landmark Lancet series emphasises the importance of access to effective healthcare for this community.9,10