Fine-Needle Aspiration “Mapping” of Testes - Diagnosis of Male Infertility

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Figure 42-12)

Although testicular sperm is used with IVF and ICSI to achieve pregnancies, there is a failure to obtain sperm in 25-50% of men with testis failure. When testis biopsies fail to retrieve sperm, IVF cycles are canceled at great emotional and financial cost. To minimize the chance of failed sperm retrieval, percutaneous fine-needle aspiration and “mapping” of the testis has been described. This technique can detect sperm in 60% of men with nonobstructed azoospermia and has confirmed that spermatogenesis can vary geographically in the failing testis such that “pockets” of sperm can exist.

Like a testis biopsy, fine-needle aspiration procedure is performed under local anesthesia. Percutaneously aspirated seminiferous tubules from various locations in the testis (5-10 mg) are smeared on a slide, fixed, stained, and read by a cytologist for the presence or absence of sperm. The information gained from this technique can fully inform patients of their chances of subsequent sperm retrieval for IVF and ICSI.

Semen Culture

Seminal fluid that passes through the urethra is routinely contaminated with bacteria. This can make the interpretation of semen culture difficult. Thus, semen cultures should not be obtained at random, but only in selected situations, given that 83% of all infertile men will have positive semen cultures and that the relationship between bacterial cultures and infertility is at best inconclusive. Semen cultures should be obtained when there are features suggestive of infection, including (1) a history of genital tract infection, (2) abnormal expressed prostatic secretion, (3) the presence of more than 1000 pathogenic bacteria per milliliter of semen, and (4) the presence of > 1 × 106 leukocytes per milliliter of semen (pyospermia).

The agents most commonly responsible for male genital tract infections are listed in

Table 42-10. Gonorrhea is the most common infection. Ten percent to 25% of chlamydial infections may be asymptomatic. Trichomonas vaginalis is a protozoan parasite responsible for 1-5% of nongonococcal infections; it is usually symptomatic. Ureaplasma urealyticum is a common inhabitant of the urethra in sexually active men (30-50% of normal men) and is responsible for one-fourth of all cases of nongonococcal infections. Escherichia coli infections are relatively uncommon in young men and are usually symptomatic. Mycoplasmas are aerobic bacteria that are known to colonize the male reproductive tract. Rarer but possible causes of infection include anaerobic bacteria and tuberculosis.

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Revision date: June 14, 2011
Last revised: by Amalia K. Gagarina, M.S., R.D.