| from
the book How to Have a Baby: Overcoming Infertility
by Dr. Aniruddha Malpani, MD and Dr. Anjali Malpani,
MD.
Previous page:
Beyond the
Semen Analysis (Page 1)
Next page: Diagnosis
and Treatment for Male Infertility -- More Confusion!
Table of Contents
Of
what use is an ultrasound exam in evaluating an infertile
man ?
Of
what use is a testicular biopsy ?
For most infertile men, the
semen analysis is the only test which needs to be done
- after all, the only job of a man is to provide sperm
to fertilise the egg ! For men with a low sperm count,
there is no need to do any other tests, since these
do not provide any useful information. However, many
doctors still do blood tests for measuring the levels
of key reproductive hormones, such as prolactin, FSH,
LH and testosterone. These are just a waste of time
and money since they provide no useful information and
do not alter the treatment plan.
For men with azoospermia
( zero sperm count), additional blood tests may be useful
. The serum FSH (follicle-stimulating hormone) level
test is a useful one for assessing testicular function.
If the reason for the azoospermia is testicular failure,
then this is reflected in a raised FSH level. This is
because, in these patients, the testis also fails to
produce a hormone called inhibin (which normally suppresses
FSH levels to their normal range). A high FSH level
is usually diagnostic of primary testicular failure,
a condition in which the seminiferous tubules in the
testes do not produce sperm normally, because they are
damaged.
This test is done by a radioimmunoassay
or chemiluminescent assay, and since it is a sophisticated
test, it is best done in a specialized laboratory. Abnormal
test results should be repeated and rechecked for confirmation.
The other reason for a high FSH level in some men is
the consumption of clomiphene (a medicine often prescribed
for the empiric treatment of oligospermia). This is
why the test should be done only when no medication
is being taken. While a high FSH level is diagnostic
of testicular failure, a normal FSH level provides no
useful information. Thus, men with complete testicular
failure may also have normal FSH levels.
While a high FSH level suggests
primary testicular failure, it cannot differentiate
between partial testicular failure and complete testicular
failure. This means that even men with very high FSH
levels can have occasional areas of sperm production
in their testes, and these testicular sperm can be used
for TESA-ICSI
( testicular sperm aspiration and intracytoplasmic sperm
injection) treatment.
Rarely, the FSH level may
be low. A low FSH level is found in patients with hypogonadotropic
hypogonadism. Hypogonadotropic hypogonadism is an uncommon
(but treatable!) cause of azoospermia. Along with an
FSH level test, most doctors also do a LH (luteinizing
hormone) level test, which provides mostly the same
information.
A testosterone level test provides information
on whether or not the testes are producing adequate
amounts of the male hormone, namely, testosterone. Most
infertile men have normal testosterone levels, because
the compartment for testosterone production is separate
from the compartment which produces sperm, and is usually
intact in infertile men. A low testosterone level causes
a decreased libido and this can be treated by testosterone
replacement therapy in the form of tablets or injections.
Of course, this therapy will not increase the sperm
count.
For men with azoospermia and erectile
dysfunction, measuring the prolactin level will help
to detect men who have hyperprolactinemia ( high prolactin
levels). Though this is a rare problem, they can be
effectively treated with medical therapy with bromocriptine
and the results are very gratifying.
Of
what use is an ultrasound exam in evaluating an infertile
man ?
An ultrasound of the testis has become a popular test
to perform, but its helpfulness is limited. The size
of the testis is better assessed by clinical examination,
using an orchidometer ( which consists of a string of
graduated plastic ovoids on a string, and can be used
to assess testicular volume by comparison) ; and while
a Doppler ultrasound will often diagnose the presence
of a varicocele, this is usually of little clinical
significance. The danger of finding a varicocele is
that the knee-jerk response is to do surgery to correct
it , and this rarely benefits the patient. A transrectal
ultrasound (TRUS) can be useful, but only in evaluating
selected patients with obstructive azoospermia, when
a block at the level of the seminal vesicles is suspected
because of ejaculatory duct obstruction, and this test
is best ordered by a specialist. Unfortunately, a lot
of doctors will order these tests "routinely" for all
infertile men, without thinking critically.
Of what use is a testicular
biopsy ?
A testicular biopsy is done in order to find out whether
sperm production in the testis is normal or not. This
is the "gold standard" for judging testicular function,
since here the testicular tissue is being examined directly.
How is a testicular biopsy performed? This is a simple
surgical procedure, which can be done under a local
anaesthetic, in an operation theatre or even in the
doctor's clinic, if it is well equipped. The test takes
about 5-10 minutes to be carried out; and a biopsy could
be taken from just one testis, or from both testes,
depending upon the nature of the problem.
The removed bit of tissue is then placed
in a special preservative fluid called Bouin's fluid,
which is then sent to a pathologist for examination
under a microscope after staining.
The biopsy surgery doesn't hurt, because
the local anesthetic numbs the tissues. There may be
dull ache for a few days after the procedure, but this
can be relieved by mild analgesics.
Since testis biopsy is a surgical procedure,
most doctors would use it as the last resort when testing
the man. If you are advised to have a testis biopsy,
ask the doctor how the result will change your treatment
(a question you should ask before being subjected to
any medical test, in fact!).
The only group of infertile men who
should be offered a testis biopsy are those with azoospermia.
Men with oligospermia should not be subjected to a testis
biopsy because the biopsy report is always normal in
these men (and this is not surprising - after all, since
sperm are present in the semen, they are obviously being
produced in the testes!)
Formerly, when doctors performed a testis
biopsy, they would send only one chunk of tissue for
testing. However, today we know that a single biopsy
may not be representative of the entire testis. Sperm
production is not uniformly distributed throughout the
testis, especially in men with testicular failure. This
means that in order to get a true picture of sperm production
in the testis, the doctor needs to sample at least 4
different areas of the testis, all of which need to
be examined. You should also insist that your doctor
send the testicular tissue to the pathology laboratory
in a special preservative called Bouin's fluid.
In the past, a testis biopsy was purely
a diagnostic procedure. Today, it is also used to retrieve
testicular sperm in order to treat men with severe male
factor infertility. These testicular sperm can be used
for intracytoplasmic sperm injection
(ICSI). Specialised infertility clinics also
have the ability to freeze the testicular tissue. This
testicular sperm freezing can be very useful, especially
in men with small testes, as the biopsy does not need
to be repeated again during treatment.
While the biopsy is an easy test to perform, it is difficult
to interpret properly, unless done by an expert. The
doctor looks for evidence of sperm production in the
seminiferous tubules. In some cases, there is no sperm
production at all (absent spermatogenesis); or the sperm
production is arrested at a particular stage (maturation
arrest) This implies testicular failure, which is usually
irreversible, and there is no treatment for this malady.
If, on the other hand, sperm production in the testes
is completely normal, and yet there are no sperm in
the ejaculated semen, this clearly means that there
is a block in the male reproductive tract. This is the
one condition in which a testis biopsy is extremely
useful (i.e., in the evaluation of the azoospermic male,
to determine if there is a block to sperm transport).
A testis biopsy is often a procedure
which is done badly because it is so "minor" so beware!
It is preferable that the biopsy be done by a specialist;
a poorly done biopsy may make reconstructive surgery
on the epididymis more difficult later on, by causing
adhesions and fibrosis (scarring). The commonest problem
with the biopsy, however, is that the biopsy result
is not reported accurately by the pathologist. Interpreting
a testis biopsy is difficult and requires special expertise
and is not something that the ordinary pathologist does
well. You should retrieve and retain your own slides
and preserve them carefully. The pathology laboratory
can also be instructed to keep the tissue ("blocks")
carefully. It is unfortunately common to find that a
testis biopsy has to be repeated simply because the
first one was done so badly that its results could not
be accurately interpreted. It may also be a good idea
to get a second specialist's opinion on the testis biopsy
slides.
Vasography is another surgical test
in which a radio- opaque dye is injected into the vas
to determine if it is open, and, if blocked, to find
out the exact site of the block. This test requires
very delicate surgery and X-ray equipment and is a very
infrequently done procedure because it can damage the
vas.
For some men with testicular failure,
a karyotype (study of the chromosomes) is useful, because
it allows one to determine if a chromosomal problem
(e.g., Klinefelter's syndrome, 47, XXY, with an extra
X Chromosome) is responsible for the azoospermia. Some
clinics also offer testing for microdeletions on the
Y-chromosome
( mYC) a newly discovered cause for testicular failure
in about 15% of infertile men. While there is no treatment
for this disorder, at least the test result provides
an answer to the question of why the testes have failed
a question which, unfortunately, medicine today still
cannot answer, in the majority of patients.
Next page: Diagnosis
and Treatment for Male Infertility -- More Confusion!
Previous page:
Beyond the
Semen Analysis (Page 1)
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