Obstructive azoospermia is characterized by? (AIPG 2011)
|A||FSH & LH levels normal|
|B||Increased FSH and Low LH|
|C||Increased LH and Low FSH|
|D||Both, FSH and LH low|
FSH and LH levels are normal
a. A normal testicular biopsy in an azoospermic man with a normal FSH level suggests obstruction of the vas.
b. The function of the testes is dependant upon hormones from the pituitary gland, follicle stimulating hormone (FSH) and luteinizing hormone (LH).
c. The blood levels of these hormones rise during the early stages of puberty and stimulate testicular development.
d. LH controls production of the male sex hormone testosterone which in turn is responsible for the growth that occurs at puberty: development of the genitals, beard and body hair, prostate and seminal vesicles, and also development of bone and muscle and other aspects of masculine physique.
e. If LH and FSH are deficient, the tests do not develop or function properly. In contrast, if the testes are damaged directly, the levels of these hormones in the blood rise.
g. There are three major groups of causes of male genital tract blockages:
a. disorders of development of the epididymis, vas and seminal vesicles,
b. scarring from inflammation (especially gonorrhoea) and
h. Rarely other blockages may occur in the vas and ejaculatory ducts. Some patients can be treated with bypass surgery, joining the tube in the epididymis above the blockage to the vas deferens.
i. The results depend on the level of the blockage, being poor with blockages close to the testis.
j. This is partly because the sperm are immature, having not passed through parts of the epididymis in which maturation usually occurs.
k. With blocks in the tail of the epididymis or vas, sperm appear in the semen of up to 80% of men after surgery, although only about half of these produce pregnancies within one year.
l. It is possible to obtain sperm by a surgical operation from the tubes above the obstruction, by sucking liquid out of the epididymis or epididymal cysts through a needle or from a testicular biopsy.
m. These sperm can be used for intracytoplasmic sperm injection (ICSI) with in vitro fertilisation (IVF).
n. This approach is particularly useful for: absence of the vasa deferentia, high epididymal obstructions for which the results of surgery are predicted to be poor, and failures of vasectomy reversal or other operations.
o. Transrectal ultrasound (TRUS) is used to support the diagnosis of ejaculatory duct obstruction in the azoospermic patient.
p. Absence of the seminal vesicles or distention due to distal obstruction can be identified. This study should be preceded by measurement of fructose in the ejaculate (lack of fructose suggests obstruction of the ejaculatory duct) and examination of postejaculate urine (to determine the presence of sperm, suggesting retrograde ejaculation).