Mehmet TOSUN, Emin Savaş KILAVIZ, Ahmet Rıza URAS

Comparison of the values of free testosterone with free androgen index

Amaç: Testosteron erkeklerde birincil ve ikincil seks karakterlerinin gelişmesinden başlıca sorumlu hormon- dur. Ancak birçok biyokimyasal parametrede olduğu gibi testosteronun biyolojik aktif olan kısmı, serbest olanıdır. Serbest androjen indeksi; total testosteronun, seks hormon bağlayıcı globüline oranıdır. Bu çalışmada biz, rutin laboratuarda serbest testosteronun ölçülemediği durumlarda, plazma serbest androjen indeksi değerle- rinin serbest testosteron yerine kullanılıp kullanılmaya- cağını araştırmayı amaçladık. Materyal ve Metot: Çalışmaya total testosteron ve serbest testosteron parametreleri ölçüm istemi yapılmış 92 kişi dahil edildi. Bu kişilerden total testosteron ve seks hormon bağlayıcı globülin parametreleri kemilümi- nesans yöntemi ile ölçülerek serbest androjen indeksi hesaplandı. Yine bu kişilerden radyoimmünoassay ile serbest testosteron ölçülerek, serbest androjen indeksi ile kıyaslandı. Bulgular: Çalışma grubuna alınan kişilerde; hesaplanan serbest androjen indeksi ile, ölçülen serbest testosteron değerleri arasında istatistiksel anlamlı ilişki bulundu. Sonuçlar: Serbest testosteron düzeylerinin belirlenme- sinde serbest androjen indeksi maliyet etkin alternatif bir yöntemdir.

Serbest androjen indeksi ile serbest testosteron değerinin karşılaştırılması)

ABSTRACT Background: Testosterone is primarily responsible for the development of male primary and secondary sex characters. However, like many biochemical parame- ters, biologically active portion of testosterone is the free one. Free androgen index is the ratio of the total testosterone to sex hormone-binding globulin. In this study, we aimed to investigate possibility of using free androgen index instead of the free testosterone when the free testosterone can not be measured routine laboratory. Material and Methods: Measurement of the total testosterone and free testosterone parameters asked 92 people were included in the study. Total testosterone and sex hormone-binding globulin parameters of these people measured with the chemiluminescence method by these parameters the free androgen index was calculated. Free testosterone measured by radioimmu- noassay, and compared with the free androgen index among these people. Results: Statistically, significant relationship was found between calculated with the free androgen index and the measured free testosterone values among the study groups. Conclusions: Free androgen index is an alternative cost-effective method and may be used to evaluate the free testosterone levels.

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