Carnitine in seminal fluid as parameter for the epididymal function

Carnitine represents the secretion which is added to human seminal fluid by the epididymis. More than 94% of the free carnitine originates from the epididymis. The frequency distribution of carnitine concentration is investigated with patients showing a normal spermiogram and with those suffering from azoospermia. Correlations with conventional spermiogram parameters are discussed. The clinical significance of the carnitine determination is shown in various andrological clinical pictures, with special consideration given to postvasectomy semen and Klinefelter's Syndrome. Two case reports of high blockages in the male reproductive tract demonstrates the diagnosis of such a blockage with the simultaneous determination of fructose, citrate and carnitine. The evaluation of split ejaculates confirms that free carnitine does not originate from seminal vesicles, but rather flows into the seminal fluid via the ductus deferens.