Testosterone and the Free Androgen Index (original) (raw)

Abstract

Testosterone measurements are very helpful in the evaluation of hypogonadal states in males, and hirsutism and virilism in females.

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  1. Testosterone measurements are crucial for diagnosing hypogonadism in males and hirsutism in females.
  2. The free androgen index (FAI) indicates abnormal androgen status and is calculated from total testosterone and SHBG levels.
  3. In women, testosterone originates mainly from peripheral conversion of androstenedione and DHEA, not the ovaries.
  4. Elevated FAI is associated with conditions like severe acne and polycystic ovarian disease.
  5. SHBG significantly influences free testosterone levels, with lower SHBG increasing bioactive testosterone availability.

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References (10)

  1. Barbieri RL. Hyperandrogenism. In: Wallach EE, Zacur HA, editors. Reproductive medicine and surgery. New York: Mosby, 1995; 209-29.
  2. Blight LF, Judd SJ, White GH. Relative diagnostic value of serum non-SHBG-bound testosterone, free androgen index and free testosterone in the assessment of mild to moderate hirsutism. Ann Clin Biochem 1989; 26:311-6.
  3. Déchaud H, Lejeune H, Garoscio-Cholet M, Mallein R, Pugeat M. Radioimmunoassay of testosterone not bound to sex-steroid-binding protein in plasma. Clin Chem 1989; 35:1609-14.
  4. Haning RV. Testosterone, a follicular regulator: key to anovulation and ovarian interaction with the adrenal. Semin Reprod Endocr 1995; 13(4):288-97.
  5. Ismail AAA, Astley P, Burr WA, Cawood M, Short F, Wakelin K, et al. The role of testosterone measurements in the investigations of androgen disorders. Ann Clin Biochem 1986; 23:113-34.
  6. Loric S, Guéchot, Duron F, Aubert P, Giboudeau J. Determination of testosterone in serum not bound by sex-hormone-binding globulin: diagnostic value in hirsute women. Clin Chem 1988; 34:1826-9.
  7. Ooi DS, Wang D, Innanen VT, Donnelly JG, Wells G. Free testosterone reference intervals in males using DPC's Coat-A-Count Free Testosterone. Poster presented at the 28th Meeting of the American Association for Clinical Chemistry; 1996 July 28 --Aug 1; Chicago. (Abstract published in Clin Chem 1996; 42(6):S233.)
  8. Paulson JD, Keller DW, Wiest WG, Warren JC. Free testosterone concentration in serum: elevation is the hallmark of hirsutism. Am J Obstet Gynecol 1977; 128: 851-7.
  9. Selby C. Sex hormone binding globulin: origin, function and clinical significance. Ann Clin Biochem 1990; 27: 532-41.
  10. Smith SW. Free Testosterone. AACC Endo 1993; 11(3):59-62.