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The pituitary in klinefelter syndrome
B W Scheithauer1, M Moschopulos, K Kovacs
1Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota 55905, USA. scheithauer.bernd@mayo.edu
Endocrine Pathology
|October 4, 2005
Summary
Klinefelter syndrome (XXY) may cause pituitary changes, including gonadotroph adenomas and hyperplasia, due to prolonged low androgen feedback. These findings highlight potential pituitary alterations in this genetic condition.
Area of Science:
- Endocrinology
- Genetics
- Pathology
Background:
- Klinefelter syndrome is a genetic disorder characterized by the XXY karyotype, leading to primary gonadal defect with low testosterone and elevated gonadotropins.
- Previous studies have not extensively detailed pituitary gland alterations in Klinefelter syndrome patients.
Observation:
- Three male patients with confirmed Klinefelter syndrome were studied, including one with a sellar mass and two with cardiac failure.
- Pituitary tissue was analyzed using immunohistochemistry for hormone immunoreactivity.
Findings:
- The first patient presented with an oncocytic gonadotroph macroadenoma, immunoreactive for FSH and alpha subunit, with no discernible pituitary gland.
- The other two patients exhibited gonadotroph hyperplasia, including "gonadal deficiency cells," and one had a growth hormone (GH)-immunoreactive microadenoma.
Implications:
- Prolonged stimulation of pituitary gonadotrophs, resulting from insufficient androgen feedback in Klinefelter syndrome, may contribute to adenoma and hyperplasia development.
- The observed pituitary changes underscore the complex endocrine interactions in Klinefelter syndrome and suggest potential targets for future research.
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