WHEN DO WE NEED SEMEN BIOCHEMISTRY ?
Semen biochemistry is necessary when there are no spermatozoa in a semen sample, ie in cases of azoospermia.
One of the causes of azoospermia is obstruction that occurs in the male reproductive system. The obstruction can be confirmed by the use of marker molecules. Fructose, acid phosphatase and a-glucosidase are routinely used when obstruction is suspected and, depending on the marker molecule, the location of the obstruction can also be determined.
WHEN IS ONLY THE MEASUREMENT OF A-GLUCOSIDASE NEEDED ?
Usually, when an obstruction occurs, the semen sample has a very low volume and a low pH. There are samples however, that are azoospermic due to obstruction but the volume of the semen sample is normal. In these cases the obstruction is near the epididymis and does not obstruct the passage of the liquids produced by the prostate and the seminal vesicles. Since neutral a-glucosidase is exclusively produced by the epididymis, a-glucosidase is the marker that can detect the obstruction near the epididymis.
HOW ARE THE MEASUREMENTS OF SEMEN BIOCHEMISTRY DONE ?
The secretions of the accessory glands are detected in the seminal plasma by the methods proposed by the WHO Laboratory Manual for the Examination and Processing of Human Semen. The methods of detection are based on the spectrophotometric detection of the compound of interest, after biochemical reactions. The absorption read by the photometer is converted to the amount of the substance with the use of a standard curve.