Klinefelter Syndrome: Detecting Hypogonadism and Differentiating from Other Causes in 47,XXY Karyotype Patients

The Klinefelter syndrome is the most common chromosomal anomaly in men, characterized by the presence of a karyotype 47,XXY. This syndrome is frequently associated with hypogonadism, resulting in androgen deficiency and altered spermatogenesis. Early detection and differentiation from other causes of hypogonadism are crucial for the appropriate management of affected patients.

Detection of Hypogonadism in Klinefelter Syndrome

Hypogonadism in Klinefelter syndrome typically manifests with low testosterone levels and elevated luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels, indicating hypergonadotropic hypogonadism. However, in rare cases, low gonadotropin levels have been reported, complicating the diagnosis [1]. Endocrinological evaluation is essential to confirm the diagnosis and differentiate it from other causes of hypogonadism, such as constitutional delay of puberty or central hypogonadism [2].

Differential diagnosis is fundamental, as other conditions, such as Kallmann syndrome or mild androgen insensitivity, may present similar clinical features [3]. Additionally, the possibility of chromosomal mosaicism, such as 9p tetrasomy, should be considered, as it can mimic the phenotype of Klinefelter syndrome [4].

Conclusions

The management of Klinefelter syndrome requires a multidisciplinary approach that includes testosterone replacement therapy to correct androgen deficiency and address learning and developmental difficulties [5]. Early detection and accurate differentiation from other causes of hypogonadism are essential to optimize clinical outcomes and improve the quality of life for patients. Continuous education and awareness about Klinefelter syndrome are vital to enhance the diagnosis and treatment of this common yet often underdiagnosed condition.

Referencias

• [1] Klinefelter syndrome with low gonadotropin levels.
• [2] Recent advancement in the treatment of boys and adolescents with hypogonadism.
• [3] Genetic mutations contributing to non-obstructive azoospermia.
• [4] Mosaic tetrasomy 9p case with the phenotype mimicking Klinefelter syndrome and hyporesponse of gonadotropin-stimulated testosterone production.
• [5] Klinefelter syndrome and its variants: an update and review for the primary pediatrician.

Created 13/1/2025