Endocrine Abstracts

Introduction: Klinefelter`s syndrome is a chromosomal abnormality characterised by presence of one or more extra X chromosome(s). The commonest karyotype is 47 XXY. We report a case of craniopharyngioma in a patient with Klinefelter`s syndrome.

Case report: A 72-year-old single male presented with three-month history of decreased left eye visual acuity with associated frontal headache and lethargy. His past medical history included osteoporosis and Klinefelter`s syndrome (47,XXY/ 46,XY karyotype) diagnosed 40 years previously. He was never sexually active.

On examination he had a complete left temporal field loss and partial right upper temporal quadrantopia. He had a hypogonadal appearance with absence of axillary, facial and pubic hair. He also had small bilateral testes.

MRI scan revealed a suprasellar mass suggestive of a craniopharyngioma. Basal and dynamic pituitary function tests showed panhypopituitarism and serum testosterone was low.

He underwent radiotherapy, which resulted in a marked improvement in his visual symptoms. He was started on thyroxin and steroid replacement and oral biphosphonates.

Discussion: Patients with Klinefelter`s syndrome have a predisposition to the development of neoplasia, particularly breast and extragonadal germ cell tumours. Involvement of the CNS, in particular suprasellar region, has rarely been described. To our knowledge this is the first reported case of craniopharyngioma in a patient with Klinefelter`s syndrome. His long-standing hypogonadism and impotence has been attributed to his chromosomal abnormality. However, the presence of a normal XY cell line in patients with 46,XY/47,XXY mosaicism should have caused a lesser degree of androgen deficiency and Symptoms of loss of libido and impotence may not appear until the fourth or fifth decade.

It is tempting to speculate that craniopharyngioma is commoner in patients with Klinefelter`s syndrome, as are other neoplasias and genetic malformations but under diagnosed because hypogonadism often solely attributed to the Klinefelter`s syndrome.