Genetic Analysis - ( Fertility )

Genetic tests are necessary in the following conditions:

1-Suspicion of a genetic cause of infertility:

Abnormalities in chromosomes may lead to infertility. An example is "Klinefilter" (KF) syndrome, where an extra "X" chromosome leads to complete arrest of spermatogenesis (sperm formation) and the testis becomes small and firm. Another condition is cases of congenital absent vas deferens.

The value of genetic analysis in these cases is determination of the most suitable way of treatment (KF requires ICSI from testicular sperm if any), as well as prevention of transmission of the same defect to the upcoming children (congenital absence of the vas).

Genetic tests include karyotyping and PCR.
 
Hormone Analysis


 FSH


Is secreted by the pituitary gland (in the brain)to stimulate the testis to produce sperm. Its level is regulated by the activity of the testis. If activity is weak, FSH level rises to activte the testis further. If activity is fine, the level becomes within normal. If FSH is too low, this indicated failure of the pituitary gland.


 Prolactin


Increased prolactin levels leads to decreased activity of the testis, infertility and erectile dysfunction (impotence). Prolactin level changes through the day. The sample must be taken in the morning considering the biological clock of the human body. Prolactin level must be elevated at least double fold on repeated samples for the elevation to considered of value. Extreme elevation in prolactin level may be related to benign brain tumors and an x-ray or CT of the skull are then necessary.

 Testosterone

Is the hormone responsible for mmasculinity. It is secreted by the testis under influence of "LH", a hormone produced by the pituitary gland present in the brain. Decreased testosterone level may lead to infertility and impotence. This decrease may be due to failure of the testis (in which case LH level is high) or failure of the pituitary (LH level is low).

Testosterone must be measured in the morning (9-11AM) as it is highest in the morning. Two forms of testosterone should be measured: Free and Total.


Estradiol

Estradiol is related to femininity, but is nevertheless present in every man's blood. If its level rises above the normal values, it can result in infertility and impotence. Some testicular tumors may result in a rise in estradiol level. It is therefore important to check for the source of this rise, particularly by tumor markers and ultrasound.


Urine and Prostate Examination


Examination of urine and prostatic expressate are important in cases of infection. Their analysis determines the degree of infection by counting pus cells, and culture sensitivity can be performed to determine the best antibiotic for treating the infection.

Prostatic expressate is obtained by massaging the prostate by a finger in the anus. Though it sounds painful and embarrassing, it is not so if performed gently, slowly and with experienced hands. It should be restricted for indicated cases. Repeated massaging of the prostate is of no clinical value and should not be performed.


Imaging


Duplex Ultrasound

 o Scrotal Duplex


Is important for diagnosing varicocele, hydrocele, accurately determining testicular size and checking the testis for tumors. Duplex ultrasound for varicocele is much more accurate than clinical examination by the hand. To diagnose varicocele, the diameter of the scrotal veins should be more than 1.7mm, and preferably be associated with "reflux on Valsalva", which is reversal of the direction of blood flow in the vein upon straining.


o Trans Rectal Ultrasound (TRUS)
Is necessary for diagnosing ejaculatory duct obstruction , congenital absence of the vas deferens, tumors of the prostate and senile prostatic enlargement. It is performed by inserting a detector (probe) into the anus by using a lubricant that decreases discomfort to a great extent.


oAbdominopelvic Ultrasound:


Is necessary for determining the presence and position of the testis in case of undescent of the testis. It is also useful for checking the renal system (Kidney, ureter and bladder) for stones in case of infection, and abnormalities in cases of congenital absence of the vas deferens. It has to be noted that in cases of undescended testis, the most accurate diagnosis is by laparoscopy (abdominal endoscopy).


-Roentgenogram (X ray)


§ Skull Xray
Is useful for diagnosis of brain tumors in cases of increased prolactin level and decreased FSH/LH/Testosterone.

§ Renal System (Kidney, ureters and bladder):

A dye is used to check these organs for stones and abnormalities.


§ Vasography
Is xray of the vas deferens with injection of a dye to determine the site of obstruction. It should not be done except during surgery for correction of obstruction, since office vasography carries a risk of occluding the vas at the site of needle entry ( a needle is used to inject the dye)

Testicular Biopsy

In cases of severe decrease of sperm or total absence, a biopsy is necessary to check whether the decrease/absence is due to low activity of the testis, or due to obstruction of the vas deferens in the presence of normal activity of the testis.

Testicular biopsy is extraction of a tiny bit i the testicular tissue and its examination. This tiny bit is extracted through a 3-5mm long incision, under local anesthesia. The incision is closed by one or two sutures that dissolve spontaneously after a while. The procedure takes around ten minutes and the patient is discharged from hospital after 1 or 2 hours.
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