[Transferrin concentration in seminal plasma in testicular varicocele with various sperm concentrations and various forms of azoospermia]

Seminal plasma transferrin concentrations were measured in semen samples from 424 men attending a fertility unit. There was a clear positive correlation between seminal plasma transferrin concentration and sperm density: transferrin concentrations decrease with decreasing sperm density and are lowest in patients with azoospermia and those who have undergone vasectomy. The differences between the various groups in sperm density are highly significant, but individual data counts also vary widely. Furthermore, it was demonstrated that in polyzoospermia the seminal plasma transferrin concentration is increased, suggesting primary tubular hyperactivity. No correlations with other seminal parameters or hormonal values were found. Seminal plasma transferrin concentrations in normozoospermia and in varicocele testis or in cases with increased numbers of immature germ cells in the ejaculate were not significantly different. This may be interpreted as indicative of intact secretory activity of Sertoli cells in both varicocele and increased desquamation of immature germ cells. The absence of correlation with any of several important spermatological parameters and our inability to differentiate between azoospermia caused by obstruction and by tubular impairment indicate that seminal plasma transferrin is not a useful marker for Sertoli cell function or for seminiferous tubular dysfunction.