|
RE: TESTICULAR HISTOPATHOLOGICAL DIAGNOSIS AS A PREDICTIVE FACTOR FOR
RETRIEVING SPERMATOZOA FOR ICSI IN NON-OBSTRUCTIVE AZOOSPERMIC PATIENTS
(
Download pdf )
GLINA S, SOARES
JB, ANTUNES JR N, GALUPPO AG, PAZ LB, WONCHOCKIER R
Int Braz
J Urol. 2005; 31: 338-341
Dear
Editor,
ICSI has allowed some couples to have genetic
offspring using a small number of spermatozoa from the testes. It seems
that these patients have small foci of spermatogenesis in the testes even
though remaining azoospermic. It is possible that they present a minimum
quantitative threshold of spermatogenesis which must be exceeded for any
spermatozoa to reach the ejaculate, estimated to be 4 to 6 mature spermatids
per tubule (1). Conventional teaching has been that men with azoospermia
and serum follicle-stimulating hormone concentrations more than 2 to 3
times normal have severe testicular failure not amenable by any conventional
therapy. However, Kim et al. demonstrated that, 30% of those men who were
previously advised against testicular biopsy if atrophy was present, were
potentially able to initiate a pregnancy in the era of testicular sperm
extraction with advanced micromanipulation techniques (2).
We have read with great interest the recent
article by Glina et al. showing that the percentage of patients with positive
sperm retrieval according to histological testicular pattern was 50% in
patients with hypospermatogenesis, 33% in patients with maturation arrest,
and 40% in patients with Sertoli cell only syndrome. Even though differences
in sperm retrieval compared to other series (80% for hypospermatogenesis,
50% for maturation arrest and 20% for Sertoli cell only syndrome) have
been brought to our attention, an important message was delivered by their
article. The pregnancy rate was only 3/16 procedures, (18.75%) in patients
with non-obstructive azoospermia. This does not differ from a previous
study that showed a pregnancy rate of 22% in patients with non-obstructive
azoospermia (3). Non-obstructive azoospermic patients may be suffering
from a genetic defect or a genetically determined barrier to reproduction.
Therefore, it is not surprising that, despite succeeding in extracting
live spermatozoa in non-obstructive cases of azoospermia, the pregnancy
rates are significantly lower when compared to those with obstructive
azoospermia (4).
Y-chromosome microdeletion screening is
recommended in cases of severe spermatogenetic impairment by numerous
societies (Société Française de Génétique
Humaine, European Society of Human Reproduction and Embryology, European
Association of Urology and American Urological Association). Investigators
identified different chromosomal regions containing independent loci related
to male gametogenesis and azoospermia (azoospermia factors, or AZFs).
More specifically, at least 3 non-overlapping regions of Yq (called AZFa,
AZFb, and AZFc) have been firmly related to male infertility, which may
be related with the possibility of sperm retrieval for assisted reproductive
techniques. Consequently, molecular diagnosis of Y-chromosome microdeletions
is now available and routinely indicated in subfertile patients with low
sperm concentrations (< 5 X 106/mL). As many cases of male infertility
are likely to be of a genetic origin, the potential risk of transmitting
infertility to future generations is of great concern. In fact, any patient
with secretory azoospermia should undergo a Karyotype and Y chromosome
microdeletion search. Therefore, the authors should state the reason for
not asking for Y microdeletion evaluation.
REFERENCES
- Silber SJ, Nagy Z, Devroey P, Tournaye H, Van Seirteghem AC: Distribution
of spermatogenesis in the testicles of azoospermic men: the presence
or absence of spermatids in the testes of men with germinal failure.
Hum Reprod. 1997; 12: 2422-28.
- Kim ED, Gilbaugh JH, Patel VR, Turek PJ, Lipshultz LI: Testis biopsies
frequently demonstrate sperm in men with azoospermia and significantly
elevated follicle-stimulating hormone levels. J Urol. 1997; 157: 144-6.
- Pasqualotto FF, Rossi-Ferragut LM, Rocha CC, Iaconelli A, Borges
E Jr: Outcome of in vitro fertilization and intracytoplasmic injection
of epididymal and testicular sperm obtained from patients with obstructive
and nonobstructive azoospermia. J Urol. 2002; 167: 1753-6.
- Buch B, Galán JJ, Lara M, Real LM, Martínez-Moya M,
Ruiz A: Absence of de novo Y-chromosome microdeletions in male children
conceived through intracytoplasmic sperm injection. Fertil Steril. 2004;
82: 1679-80.
Respectfully,
Dr.
Fabio Firmbach Pasqualotto
Professor of Anatomy and Urology
University of Caxias do Sul
Caxias do Sul, RS, Brazil
REPLY BY AUTHORS
We
fully agree with Dr. Pasqualotto that any man with severe oligospermia
or non-obstructive azoospermia that would be submitted to ICSI should
undergo a complete genetic screening. This includes kariotype and Y chromosome
microdelection search and this is part of our routine work-up. However,
we did not report that in our paper because the objective was to learn,
in our experience, the role of previous histological testicular pattern
as a prognosis for sperm retrieval in non-obstructive azoospermic men. |