[Pathogenetic and clinical aspects of low estradiol level in the man]

To elucidate a possible role of low estradiol (E2) levels in blood serum of men, normal values were determined in 91 healthy men (age 20-75 years), classified as high or low complaint-index due to a psychological questionnaire. Statistical analysis gave no correlation of estradiol levels to age or complaint index in normal men whereas testosterone (T) could be significantly correlated to complaint-index (p < 0.01) and free testosterone (fT) could be significantly correlated to age (p < 0.001) and complaint-index (p < 0.01). T and E2 were determined in 1370 clinical patients with various urological diseases, T, fT and E2 in 1261 ambulant patients. In 72/1370 (5.2%) and 76/1261 (6%) patients, low E2-levels (< 10 pg/ml) were found in blood serum. In 56/76 (74%) patients with low E2-levels, T or fT was simultaneously low. Isolated low E2-levels were found in 20/1261 (1.6%) patients. In clinical patients, no special urological disease correlated to low E2-levels. Due to these results, low E2 levels in men are in most cases the result of low testosteron levels. The adequate hormonal treatment in men is therefore the replacement of testosteron. Substitution of E2 in men is at that time an experimental therapy, that is limited on selected cases.