Table 7a. Typical findings for the history of a patient with non-obstructive azoospermia

Cryptorchidism

Testicular torsion

Genitourinary infection

Testicular trauma

Environmental toxin exposure

Gnodadotoxic medication

Radiation or chemical exposure

Groin surgeries

Testicular cancer

Table 7b. Typical findings for the physical examination of a patient with non-obstructive

azoospermia

Absense of testes

Abnormal secondary sexual characteristics

Gynaecomastia

Cryptochordism

Abnormal testicular volume and/or consistency

Varicocele

Semen analysis

In non-obstructive azoospermia, semen analysis shows normal ejaculate volume and azoospermia after several centrifugations have been performed.

A recommended method is semen centrifugation at 600 g for 10 minutes and thorough microscopical examination of the pellet (X 600). The upper fluid is then recentrifuged (8,000 g) for an additional 10 minutes and examined. All samples can be stained and reexamined under the microscope [8,9].

Hormonal determinations

FSH values are mainly correlated with the number of spermatogonia. When these cells are absent or markedly diminished, FSH values are usually elevated. When the number of spermatogonia is normal and there is complete spermatocyte or spermatid blockage, FSH values are within normal range.

Individuality, however, the role of FSH as a predictor of the status of spermatogenesis is uncertain [10-12]. Preliminary data indicate a stronger correlation between low inhibin-B level and spermatogenic damage [13]. At present, routine determination of inhibin-B is not suggested.

Special situations

Combination obstructive/non-obstructive azoospermia:

Some azoospermic patients may present with a combination of obstructive and spermatogenic pathologies and increased serum FSH levels [10]. It is therefore advisable to perform testicular biopsy in azoospermic patients with elevated FSH levels, who are known or suspected of having seminal duct obstruction, or when the size and/or consistency of one testis has decreased.

FSH levels and results of testicular sperm extraction (TESE):

Several different studies do not provide any correlation between FSH concentrations and the possibility of finding sperm in testicles with non-obstructive azoospermia [14-17].

Sertoli Cell-Only Syndrome (SCOS):

SCOS can be found in patients with normal and elevated FSH [18,19].

Patients usually present with azoospermia and normal ejaculate volume, elevated FSH, normal testosterone, LH and prolactin, normal secondary sexual characteristics and bilaterally small testes. It is suggested that the levels of LH and testosterone should be investigated only in cases with clinical signs of hypogonadism.

Genetic studies (see above Genetic disorders in infertility) Testicular biopsy

Testicular biopsy is indicated in patients without evident factors (normal FSH and normal testicular volume) to differentiate between obstructive and non-obstructive azoospermia.

Testicular biopsy can also be indicated in patients with clinical evidence of non-obstructive azoospermia who decide to undergo ICSI. Spermatogenesis may be focal. In these cases, one or more seminiferous tubules are involved in spermatogenesis while others are not [20-22]. About 50-60% of men with non-obstructive azoospermia have some seminiferous tubules with spermatozoa that can be used for ICSI (Table 6).

Date: 2016-06-12; view: 203